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COMETOF THECENTURY?What the experts say

about comet ISON

Leaving the Solar System

Curiosity’s year on Mars

Complete night sky guideVoyager heads into the unknown

The NASA rover’s story so far

All you need to know about what’s up this month

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HUBBLEREBORNThe Story of the Space Telescope

By Emily Baldwin and Keith Cooper

HU

BB

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OR

N: TH

E STOR

Y OF TH

E SPACE TELESCO

PE

Emily B

aldw

in an

d Keith

Cooper

P

ole Star Pu

blication

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THE GREATEST GALAXY IN THE SKYYour guide to observing Andromeda

Measuring the stars

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Unmasking the mysteries of an icy world

Processing the professionals’ imagesOctober 2013 £3.99

Mars meetsComet ISON

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4 Past Pages Peter GregoBetter late or never?

5 AstroNewsPlanets around other stars

Meteorites and impacts

Kepler’s new slant on exoplanets / Peter Higgs awarded Nobel Prize

10 Telescope Topics Ian MorisonObserving the Sun in the light of H-alpha, 2: Drawing and imaging the Sun in H-alpha

12 Amateur Scene Peter WadeMemories of working alongside Sir Patrick

Cloudy nights can be lively nights

Out and about / Fight night blight, get light right

Explosive start for northwest rocketeers / Host societies welcome BAA

24 Space Exploration Helen WalkerMars news roundup:

India’s first mission to the Red Planet

Hebe Chasma—a Martian supervolcano?

Methane mystery / water success

ISS activities / Near-drowning in space / Penetrator

27 Young Stargazers George Ford / Ezzie PearsonFamous astronomers: John Goodricke David Scanlan

A partial eclipse of the midnight Sun Simon Cran-McGreehin

Help! I don’t understand ... Dark matter Robin Scagell

What’s it like to work at the European Space Agency? Emily Baldwin

32 ReviewsThe Cambridge Photographic Moon Atlas / Astronomy Diary

The Clementine Atlas of the Moon

34 LettersThe Seeliger Effect—on Earth as it is on Saturn?

Nova Del 2013 / New brush sweeps cleaner

36 Section ReportsOdd flash probably no point meteor / View a scene of crater catastrophe

Northern graze

Saturn, the only game in town

Cheeseburger on chips

Will C/2012 S1 (ISON) be the comet of the century?

41 The Society PagesWonderful weekend in Belfast Paul Sutherland

Astronomer Royal addresses successful SPA Convention

Come to the SPA meeting on 25 January 2014 / Explore the Universe in Cardiff

SPA statement on threat to The Sky at Night Robin Scagell

SPA meetings to come

44 Sky Diary Peter GregoLunar occultations Mell Jeffrey

Meteor notes Tony Markham

46 SPA contacts

47 Showcase Peter GregoMembers’ images of ‘celestial rings’

FeaturesProduction

November-December 2013Volume 60Number 6

www.popastro.com

Editor / design and layout

Peter Grego

7 Parc-An-Bre Drive

St Dennis

St Austell PL26 8AS

[email protected]

Advertising Manager

Peter Grego

Distribution Manager

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PA welcomes articles on all aspects of

astronomy. Opinions expressed in PA

are not necessarily those of the SPA.

The SPA can’t be held responsible for

the accuracy of descriptive statements

or for the quality of goods advertised.

ISSN: 0261-0892

© 2013 The Society for Popular

Astronomy. Popular Astronomy is

published bimonthly for SPA members.

Annual subscription: £18. For details

about the SPA and how to join, visit:

Regulars

Cover: This combined infrared/X-rayimage of the Andromeda Galaxy (atcentre) was taken by two ESA spaceobservatories—Herschel and XMM-

Newton. Herschel finished itsmission in April 2013, but its

observations will occupy scientistsfor a long time. Images surrounding

are (clockwise from top left):infrared, X-rays, composite and

optical. See Young Stargazers forEmily Baldwin’s account of working

for ESA. Image: ESA.

9 Healing stars Paul Greenewich

16 The Goldilocks Zone, refined Tony Auffret

19 Mars, before the Space Age Professor Barrie W. Jones

PopularAstronomy

November-December 2013 www.popastro.com Popular Astronomy p3


JOHN Lytheer’s editorial comments in

Hermes (Oct-Dec 1963) consisted

entirely of an impassioned call for the

urgent establishment of a ‘National

Centre’ for UK astronomy.

‘In America, Russia and some other

countries, interest in astronomy is

carefully fostered,’ he explained.

‘Planetaria, public observatories,

sympathetic consideration of amateurs’

problems locally and positive

encouragement nationally are the order

of the day. [LOL—current editor]

‘In this country, radio and television

programmes have awakened the interest

of thousands, probably millions of

people. Thousands visit the Science

Museum and London Planetarium every

year. Hundreds attend astronomical

courses up and down the country. Great

national newspapers publish

astronomical information. Books

catering for every possible level of

knowledge or age pour in to shops and

libraries. The number of astronomical

groups and societies is growing apace.

More and more people are building their

own telescopes or seeking advice on

purchase.’

Lytheer went on to propose a large,

purpose-designed building set in country

north of London. ‘It would contain

lecture rooms, a planetarium and

demonstration facilities. Laid out partly

as a museum and partly as a display of

astronomical models, it would have a

number of first-class instruments, each

in its own dome complete with driving

mechanisms and the latest photographic

and electronic auxiliary equipment. It

would be completely equipped with radio

receivers able to pick up and record not

only natural radio emission from local

and distant space but also signals or

speech from orbiting satellites, probes or

manned space expeditions. In its

basement would be workshops where

mirrors could be ground and finished.

Lathes, machine tools and engineering

facilities for the construction of

mountings, would also be provided.

Testing shops, photographic dark-rooms,

a spectrographic laboratory and perhaps

even a small computer [:-) Ed] would be

included. Living accommodation would

be on hostel lines.’

‘At first glance it might seem insanely

impractical,’ he continued ‘but I believe

it could be achieved with the co-

operation of three Government

departments, the support of every

astronomical organisation, the

enthusiasm of every astronomer and

the goodwill of a number of

industrial companies’.

Lytheer bemoaned the lack of

vociferous activity among

astronomers and the absence of a

campaigning spirit among them,

accusing astronomers of ‘having little

fire in their bellies’ and of being

‘placid folk, content to work quietly

and in the dark’.

Lytheer’s Utopian vision of a one-

stop astronomy shop for the UK might

have sounded (and still does sound)

suspiciously authoritarian rather than

insane. The obvious contradiction and

illogic in his editorial was that while

maintaining an urgent need for a

national centre for astronomy, he

painted a glowing picture of a boom-time

for UK astronomy in 1963, with interest

in the subject being amply catered for by

the media, publishing, museums,

planetaria, commerce, various groups

and societies. If all was going so well in

the UK, why the need, let alone the

urgent need of a national centre for

astronomy?

It’s impossible to tell whether society

members responded at all to Lytheer’s

editorial, as there’s only a single

published letter (on an unrelated

subject) in all the subsequent issues of

Hermes for at least three years!

No country has ever had (nor, I think,

ever will have) a national centre along

Lytheer's lines. Besides its unfeasibly

broad remit and the sheer cost of such a

project (presumably borne by the

taxpayer), there’s the uber-Herculean

task of amicably arriving at an all-

encompassing, top-down, Government-

sponsored, committee-bound solution

that meets the approval of all parties

concerned. Then there’s the unfairness of

its single geographical location and the

perpetual political machinations that

would grind away behind (and

sometimes in front of) the scenes.

Lytheer’s vision is a ‘better never’ idea.

However, the modern entity nearest to

Lytheer’s proposal is Leicester’s National

Space Centre, which opened in June

2001. It has become the UK’s largest

visitor attraction dedicated to space and

space exploration and welcomes around

a quarter of a million visitors each year.

Originally the idea of the University of

Leicester, it was supported by Leicester

City Council and won a joint bid to the

Millennium Commission. Although far

from being a complete one-stop space

‘shop’ for astronomers, it does have a

very wide scope that successfully

conveys education, inspiration and

visual entertainment about space-related

subjects to the public. SPA members

even get a discounted entry fee—see

www.spacecentre.co.uk for more details

and www.popastro.com/discounts to find

more places in the SPA discount scheme.

In Popular Astronomy, (Oct-Dec 1988)

editor Ian Ridpath headlines the happy

news Merger saves Schmidt. He writes:

‘The UK Schmidt Telescope in

Australia has been saved from the

threat of closure by merging it with the

Anglo-Australian Observatory ... For the

past three years the Schmidt telescope

has been threatened with cut-backs or

even closure because of lack of money for

astronomy in the UK. Australian

astronomers saved the telescope by

offering to share the costs of running it.

The UK and Australia already

contribute equally to running the AAT...’

Ironically, this happened at a time of

UK economic prosperity. But, better late

than never, saving the UKST proved a

great decision. The 1.2-m telescope, now

operated by the Australian Astronomical

Observatory, lies near the 3.9-m AAT at

Siding Spring. Its worth is proven; the

main source of southern optical survey

data, its images created the Guide Star

Catalog for the Hubble Space Telescope

and the Digitized Sky Survey. It’s now

used and funded by RAVE (RAdial

Velocity Experiment)an international

project to measure a million stars.

Our human desire to understand the

Universe never ends. Sadly, science has

long been starving (not just hungry) for

taxpayer funding. The benefits of

knowledge (including boosting the

economy) are incalculable in the long

run. Further cuts simply expand fat cats,

impoverishes the people and steepens

the downward curve of UK excellence.

So, Mr Cameron: Increase funding now!

Better late than never.

Better late or never?

PETER GREGO looks at thecontents of this magazine50 and 25 years ago

Hermes (1963)

and PA (1988),

Oct-Dec issues.

Past Pages

p4 Popular Astronomy www.popastro.com November-December 2013


THE infrared Spitzer Space

Telescope and the Hubble

Space Telescope (HST) have been

studying one of the nearest

exoplanets, HD189733b, and have

come to a rather startling

conclusion that it would look like a

deep blue dot if we could resolve it.

HST observed the exoplanet

disappearing behind the star and

found that the level of blue light

dropped, but the red and green

were constant, showing that this is

a blue planet. However the deep

blue colour is the result of tiny

glass beads in the atmosphere and

not oceans of liquid water.

Spitzer showed that the

temperature on the sunny side of

the planet is 1000°C and on the

night side 750°C, so there are very

strong winds racing round from

one side of the planet to the other,

creating hazy clouds full of small

glassy particles.

Data from the Kepler satellite,

focused on the Cygnus region in

the Milky Way, is continuing to

show interesting exoplanets. One

recent discovery by Kepler is a set

of planets around a K2V star,

looking like our inner Solar

System. There are five planets, and

two of them, Kepler-62e (60% larger

than Earth) and Kepler 62f (40%

larger than Earth), are in the star’s

habitable zone.

It was always a conundrum as to

whether exoplanets would be more

likely to be found in star clusters

since many stars made it ‘easier’ to

hunt for planets, or less likely

because any planet-forming

material would be swept up by one

star or another.

Two planets have been found in

the open cluster NGC 6811, showing

that the likelihood of planets

forming around stars in clusters is

similar to other stars in our Galaxy.

Kepler-66b and Kepler-67b both

transit hot stars, and both are

around 3 to 4 times Earth’s size.

Another puzzle has always been

that planets, e.g. Jupiter, thought to

have formed in the outer Solar

System migrated inwards, with the

problem of stopping the planet

before it migrates into the Sun.

Kepler has shown that tidal, or

gravitational, forces act on the

migrating planet, circularising the

orbit and thus halting the inward

migration once a stable circular

orbit has been hit.

Kepler has been trying to sort out

problems with its gyroscopic

reaction wheels for several months,

and may no longer be able to point

accurately. This would mean the

end of a second planet-hunting

satellite, as the French satellite

CoRot ceased its operations earlier

this year due to a computer failure.

Helen Walker

Bringing the latest newsin astronomical research

and observations

p6

Timeline 2003-2013

AstroNews

Above: The first-ever map of an exoplanet—gas giant HD189733b. Made

from Spitzer’s infrared data, it shows temperature variations across the

planet’s cloud tops: higher temperatures are represented in brighter

shades. HD 189733b is a ‘hot Jupiter’, a gas planet orbiting its parent star

much closer than Mercury is to the Sun. HD 189733b completes one orbit in

just 2.2 days. Hot Jupiters are thought to be tidally locked, so one side of

the planet always faces its star. HD 189733b is hotter on its permanently

sunlit side, but the hot spot is offset from high noon by 30°. This asymmetry

is thought to be caused by strong winds pushing the hot spot eastward.

Image: NASA / JPL-Caltech / H. Knutson.

SPA celebrates its 50th year.

Cover of the Jan-Mar issue of

Popular Astronomy is specially

illustrated with art by David A. Hardy. Inside

are congratulatory letters from Patrick Moore,

Sir Martin Rees and Sir Arthur C. Clarke.

2003

A unique stellar alignment—past Presidents at the society’s Golden

Anniversary celebrations. Left-Right: Patrick Moore, Ian Morison,

Barrie Jones, Iain Nicolson, Margaret Penston (then President),

Michael Maunder, Iwan Williams, Jack Meadows, Heather Couper,

Arnold Wolfendale (Patron), Ian Roxburgh and Derek McNally.

Planets around

other stars



THE meteorite that came down over

Russia earlier in the year has

started being analysed. A team from

the Ural Federal University collected

bits of the meteorite and the analysis is

showing that it is a common chondrite,

rather than the more exotic iron

meteorite as was speculated, due to its

dramatic entry. There is olivine,

pyroxene, troilite and kamacite present,

showing the rock is indeed from outer

space. Another rock from outer space,

which came down almost 13,000 years

ago, has been tracked down through

Greenland ice cores. The ice cores

reveal a layer of enhanced platinum

and spherical-shaped particles have

been found too in sediments elsewhere,

suggesting that a large meteorite

impact caused the climate to become

colder, which has been linked to the

demise of the North American Clovis

people.

Helen Walker

The

2014

Winter

Olympics,

to be held

in Sochi,

Russia, will

have seven gold medals to be won

during 8th day medal events. These

particular medals will feature

fragments of the Chelyabinsk meteorite.

AstroNews

2003, continued ...

January: New regular

feature Space Cadets for

younger readers of PA,

renamed Prime Space in

April issue.

Ian Brantingham takes

over from Richard Pearce

at the Aurora Section.

David Hardy’s splendid

cover art graces the

Jan-Feb 2003 issue of PA.

Meteorites and impactsMeteorites and impacts

This 112 g fragment of

the Chelyabinsk meteorite

(found between the

villages of Deputatsky

and Emanzhelinsk) is one

of many that were found

within days of the airburst.

It has a thick primary fusion

crust with flow lines; its

heavily shocked matrix shows

melt veins and planar

fractures. Cube 1 cm square.

The Chelyabinsk impact took place on 15

February, deep in the Russian winter,

and a substantial fragment of it survived

the airburst to make in a hole in the

thick icy cover of Chebarkul Lake outside

the city of Chelyabinsk itself (shown at

left). On 16 October Russian scientists

recovered the fragment (possibly the

largest part of the Chelyabinsk meteorite)

from the lake. After hauling it up from

the depths, a giant steelyard

balance weighed it at 654 kg

before the balance tipped

over. As a result, the

meteorite broke into

three pieces.

Monica Grady

becomes SPA

President.

Astrophotography and CCD

imaging Sections incorporated

into Astroimaging Section under

Nik Szymanek.

Most skies across the UK were

wonderfully clear for the the

long-awaited transit of Venus on

8 June.

David Budd’s image of the

transit of Venus.

2004August:

National

Astronomy

Week centred

around Mars,

whose

opposition on

the 28th saw

the Red Planet

approach within

0.37 au from

Earth—its

closest for

60,000 years.



THE exoplanet-hunting Kepler

satellite has produced yet

another surprise discovery—an

exoplanetary system orbiting in a

plane tilted highly to the

equatorial plane of its parent star.

Kepler has determined that most

planets have orbits that closely

match their parent star’s

equatorial plane. The most highly

inclined planetary orbit in our

Solar System is 7.25° (Earth).

Kepler has discovered single

planets in highly inclined orbits

before, but this is the first time

that it has been shown in

a multiple planetary

system.

Kepler-56, consists of

two large, closely

orbiting planets (with

orbital periods of just

10 and 20 days) inclined

by a whopping 45° to

their parent star, a giant

four times the Sun’s size.

It is thought unlikely that

these planets formed at such an

angle. Instead, investigations

suggest that they have likely been

levered by

the

gravitation

of a big third

planet in a

different orbital

plane—a planet

revealed by its

gravitational tug on Kepler-56,

rather than by transit. PG

PROFESSOR Peter Higgs, the

scientist who gave his name to the

Higgs boson particle, has won the 2013

Nobel Prize in Physics. He shares the

prize with Francois Englert for their

work in the ‘theoretical discovery of a

mechanism that contributes to our

understanding of the origin of mass of

subatomic particles’.

This mechanism, postulated by Higgs

in the early 1960s, predicts a particle

responsible for giving mass to matter—

a particle known as the Higgs boson.

Having remained a theoretical entity

for half a century, the Higgs boson was

finally discovered last year by a team

from the European nuclear research

facility (CERN) in Geneva, Switzerland.

In a statement released through

Edinburgh University, where 84 year

old Higgs is an emeritus professor, he

said: “I am overwhelmed to receive this

award and thank the Royal Swedish

Academy. I would also like to

congratulate all those who have

contributed to the discovery of this new

particle. I hope this recognition of

fundamental science will help raise

awareness of the value of blue-sky

research.”

The Nobel awards were set up by

businessman and inventor Alfred Nobel

and were first given out in 1901 to

honour achievements in science,

literature and peace. Higgs takes a

place among many Nobel laureates

whose work made a significant impact

in astronomy and cosmology, including:

Albert Einstein (1921) for his work in

theoretical physics and the

discovery of the

photoelectric effect;

Anthony Hewish

and Martin

Ryle (1974)

for their

work on

neutron

stars

and

the

discovery of pulsars; Arno Penzias and

Robert Wilson (1978) for their

observation of the Cosmic Microwave

Background; and Ray Davis and

Masatoshi Koshiba (2002) for their

pioneering work in neutrino astronomy.

A full list can be found at: en.wikipedia.

org/wiki/List_of_Nobel_laureatesPG

p12

2004, continued ...

Shuttle and Spacemen by James Wright (shown

below) is the overall winner of the SPA Golden

Jubilee Design a Constellation competition.

Winner of the

Mars Scrapbook

competition is

Natalie Green

(shown at right

receiving her

award from SPA

President

Monica Grady).

AstroNews

Peter Higgs.

Peter Higgs awarded Nobel Prize

Kepler’s new slant on exoplanets

Ian Morison

becomes

SPA

Instrument

Advisor.

Veteran

amateur

astronomer

Alan Heath

wins Fred

Best award.

2005

Guy Fennimore

(right) presents

the Fred Best

award to

Alan Heath.

Barry Turvey introduces

new merchandise—a

binder for your copies of

Popular Astronomy,a

great new range of SPA

leisurewear and the SPA

teddies.

October: The first SPA

Convention is held at the

Institute of Astronomy,

Cambridge. The event

proves to be a great

success.



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Iam sitting in my hotel room 240.5 milesfrom home. The transition (yes,

‘transition’ is the right word) from there tohere has been challenging, even thoughthe car journey itself was uneventful.

I have Asperger syndrome, and for all us‘aspies’, changes of routine, changes ofenvironment, in fact changes of every kindcan be fraught with anxiety. But tonight,soon after sunset, I shall see Jupiter shininglike a jewel in the western sky—the sameJupiter I saw from my front porch yesterdayevening, and in almost the same position.And that continuity in the midst of so muchchange will steady me; it will help me to re-orientate myself; it will help me to sleep.

Asperger syndrome (AS) is a form ofautism, a developmental disorder that invarious ways, and to varying degrees(hence the term ‘spectrum disorder’) affectsthe way a person processes information,comprehends the world and relates toothers. According to the National AutisticSociety, around 1% of the UK populationmay have autism. Unlike those with classicautism, however, ‘aspies’ do not usuallyhave learning difficulties and often they areof average or above average intelligence.The long list of celebrities and highachievers who have, or are speculated tohave had Asperger syndrome comprisesmany whose names will be familiar to thereaders of this magazine, including IsaacNewton, Henry Cavendish, John CouchAdams, Marie Curie, Charles Darwin, H.G.Wells, Albert Einstein, Isaac Asimov andCarl Sagan.

As people with AS often feel as thoughthey’ve come from another planet, it’s notsurprising that many of them are drawn toastronomy and science fiction. But asidefrom this understandable interest, timespent with the stars can have a deeplybeneficial effect on those of us with AS, aswell as others on the autism spectrum. Notinfrequently, parents of autistic childrenhave reported a seemingly miraculoustransformation once a map of the stars wasput on their child’s bedroom ceiling.Previously the youngster would not settle atnight and often ended up disrupting thewhole household; now they were soon fastasleep, with the result that their overallbehaviour and well-being improved, andthey responded better to the therapies andprogrammes designed to help them.

There was no star map on my bedroomceiling when I was growing up in the1950s. In fact the syndrome, named afterthe Austrian paediatrician Hans Aspergerwho first described the condition in 1944,

did not become a standard diagnosis until1992. But from my earliest days, I insistedon having my bedroom curtains drawnback at night so that I could see the sky,and even when the stars were hidden bycloud, I would still imagine them there. Letme try to explain why for a chronicallyanxious young person given to frequentpanic attacks, the stars seemed to havesuch a calming influence—as they do tothis day.

Many people find star watching arelaxing antidote to the pace and pressuresof modern-day life. For those of us with anautism spectrum disorder, these interludescan be especially therapeutic. The ‘aspie’brain does not develop the ability to filterout the familiar or see the big picture;instead, it remains permanently attuned todetail and the uniqueness of things. As aconsequence, we find the world aconfusing and unpredictable place whereour senses are constantly being assailed byvast amounts of information that our brainsoften struggle to assimilate.

In order to cope, we rely heavily on order,routine and often rigid patterns ofbehaviour. We try to build connections andderive meaning by applying black-and-white rules, but without specifics, we can beeasily overwhelmed. By contrast with aworld that regularly frightens us with itsnoise and intensity and imponderablecomplexities, the night sky is a haven ofpeace, simplicity and order.

Against a uniformly black background(in rural locations, anyway) myriad pointsof light, in fixed relationship to oneanother, slowly orbit thecelestial pole or riseand set with unfailingpredictability. On anygiven night, we knowexactly where theMoon andplanets will be.There is nothingelse to befuddle themind; there are nojarring sounds orclashing colours—even Earth’snatural satelliteappears restfullymonochrome.And the onlyunexpectedmovement weare likely to encounteris the momentary streakof a meteor.

Some of the autistic children who focuson a map of the night sky at the end of theday find rest by memorising the names ofstars and constellations, and their relativepositions. For me, it has always been thegeometry of those relationships that I havefound harmonious, helping my mind to de-clutter and heal. It is almost as though theconstellations and asterisms provide atemplate or map for the processing brain tofollow.

Those of us with autism want to succeedin relationships, but developing friendshipscan be problematic. We lack the socialskills that ‘neurotypical’ people developnaturally; we struggle to interpret thenonverbal cues which are said to accountfor 85% of all communication betweenhuman beings. Happily, however, the nightsky can be enjoyed by anyone, regardlessof their mental disposition. You don’t evenneed a telescope. Under the cloak ofdarkness, we can converse without havingto make eye contact, which people withautism invariably find difficult. What’smore, the least stressful way we have ofrelating to others is often through a sharedspecial interest, like astronomy.

So if you know someone with an autisticcondition who hasn’t spent time beneaththe night sky, why not introduce them? Gogently, and do not proceed if they show anysigns of fear. However, for those who areinspired by your love and knowledge of theheavens, the benefits could be truly life-

changing, and as enduringas the stars themselves.

Healing starsHealing starsPAUL GREENEWICH explains how

star watching may help some peoplewith an autism spectrum disorder



GIVEN an H-alpha telescope,

one can get real satisfaction

from sketching the full solar disk

showing the sunspot groups,

filaments and prominences, such

as those drawn by my colleague

Paul Cannon and featured here.

A DSLR camera can be attached

to a solar telescope using a T-mount to

image the whole disk with one

exposure, or a compact digital camera

can be used with eyepiece projection. If

using a DSLR, a 1.25-inch barrel will

be required for the T-mount, as H-

alpha telescopes tend to have 1.25

focusers. As mentioned in the previous

article, as the sensor of a DSLR will be

further from the blocking filter, a 10 or

15 mm aperture blocking filter will be

required to avoid vignetting of the

image.

Often, however, more detail will be

captured by imaging segments of the

Sun

using a

webcam. As

the CCD sensor of a

webcam is only a few

millimetres in size and its sensor can

be placed closer to the blocking filter

than

with a

DSLR

camera, a

large

blocking filter

will not be required

so the cost of the solar telescope

will be reduced. Reaching focus using a

webcam can be assisted if necessary by

the use of a Barlow lens, removed from

its mount and screwed into the front of

the camera’s 1.25-inch nosepiece. This

will also increase the image scale of

the Sun, giving the potential for higher

resolution images but requiring more

individual images to be combined to

give a full disk image.

The image is essentially

monochrome—though it appears red to

our eyes—and thus a monochrome

webcam will be ideal. This will be

more sensitive than a colour version so

allowing shorter exposures.

I set out to image the Sun using the

Imaging Source DMK 21AU16.AS

which uses a CCD chip having an

excellent ~68% quantum efficiency.

This was initially coupled to a

Solarscope SA60 which had been

kindly loaned to me. The Sun barely

shone when I had the telescope, but

one morning I was able to take a

number of video sequences as gaps

appeared through the clouds. As the

Aspects of instruments andobserving, explained by

IAN MORISONTelescope Topics

Observing the Sun

in the light of

H-alphaPart 2: Drawing and

imaging the Sun

in H-alpha

N

E W

S

Above: Paul Cannon’s

full disk sketch of the

Sun viewed in H-

alpha light on 29 July

2012. It is labeled with

the designated

numbers of sunspot

groups. The SOHO

satellite website

provides these numbers

at sohowww.nascom.

nasa.gov/sunspots

Left: Pastel drawings

of prominences by

Paul Cannon showing

close-ups of

prominences. The

lower sketch (south at

top) is a depiction of

the dramatic

prominence shown on

the southwestern limb

of the main disk

drawing above.



Sun’s image in the image plane is not

that large, only six individual AVI

sequences were required to cover it,

whilst providing good overlap between

them. This technique is exactly the

same as when imaging the Moon with

a webcam. The individual AVI

sequences were processed in Registax

V4 and the resulting frames

composited into a single image.

The prominences are not as bright,

so a further set of AVI sequences were

taken to correctly expose them. The

prominence and solar disk images then

need to be combined. One method is to

have the two images open side by side

and simply ‘clone’ the prominences

from the brighter image over the, just

visible, faint prominences in the image

exposed correctly for the disk. The

image at right is the result this

process.

Just as a ‘monochrome’ image of the

visible Sun can be coloured, so can

that of an H-alpha image. This can be

achieved in Photoshop simply by

putting the initial image into RGB, 8-

bit mode, and then duplicating it—

Layer > Duplicate Layer. The colour

box is clicked on and a set of suitable

R, G and B numbers placed in the

panel that opens up. A good starting

point would be R = 231, Green = 33

and Blue = 11. The paintbrush is then

used to paint over the duplicate layer

to give a completely red image and, in

Layers, the blending mode is changed

to ‘Colour.’ The layers are then

‘flattened’—Layer > Flatten Image—

and the resulting image saved. The

resulting colourised version of the

solar image above is featured in this

issue’s Showcase on p47.

A Barlow lens can be used to

increase the image scale either by

using the full Barlow unit or by

screwing in its lens element into the

front of the webcam barrel to give a

lesser increase.

Rather than producing full disk

images I have tended to image

interesting areas of the Sun and two of

these are shown below. That on the

left is with the webcam mounted

directly into the telescope eyepiece,

whilst that on the right is with the

insertion of a 2.5× TeleVue Powermate

Barlow to give a detailed image of a

particularly interesting region.

In all, solar observing can be quite a

rewarding aspect of amateur

astronomy which, almost by definition,

can usually be done in the warm. Why

not give it a try?

Next issue: DSLR cameras with

modified infrared filters.

Two H-alpha webcam images of parts of the solar disk.

Images by Ian Morison.

Right: A full disk composite image of

the H-alpha Sun captured using a

webcam and stitched in Microsoft ICE.

The colour version of this image is

featured in this issue’s Showcase on

p47. Images by Ian Morison.

Telescope Topics



THE death of Sir Patrick Moore at

the end of last year has provided an

opportunity to not only look back over

his long and distinguished career but

also to celebrate the achievements of

some of those who worked alongside

him. One of these is space artist David

Hardy who recalled some of their

collaborations in Spaceflight, the

magazine of the British Interplanetary

Society.

David’s connection with Sir Patrick

dates back to 1954 when a friend of his

had visited Patrick and shown him

some of David’s artwork. An exchange

of telegrams followed in which Patrick

asked for eight black-and-white

illustrations for a book, Sun, Myths and

Men. David remembers how he had

only five days to do the job before he

joined the RAF to do his National

Service. In fact, the finished pictures

were only put in the post as David set

off to start his tour of duty.

Other collaborations followed. One

was another book, The Challenge of the

Stars, which the publishers then

thought too much of a leap into the

future. By the time mankind had

visited the Moon, it was thought the

time for the book had finally come and

it even enjoyed a revival as The New

Challenge of the Stars alongside the

release of the first Stars Wars film.

David’s work with Patrick spanned 50

years, their last major venture together

being Futures: 50 Years in Space which

showed how our ideas of both space and

space travel have changed over time.

David’s earlier pictures showed spiky

lunar landscapes which became more

smoothed and rounded by the 1970s

while streamlined spaceships and space

stations conversely became more spiky.

David also previewed human

exploration to come on Mars or Saturn’s

moon Titan. In this last subject, David

updated a classic image of Saturn

suspended in Titan’s sky created by

Chesley Bonestell.

Over the years, David’s techniques

have moved on too. Those first

illustrations in 1954 were done with

scraperboard; many later ones are in

gouache while the most recent pictures

are produced digitally.

A striking image is David’s cover for

another Patrick Moore book, The Boys’

Book of Astronomy (1958). Here David

did both the lettering and illustration

which saw him use an airbrush for the

first time to show a spiral galaxy

hovering over an observatory dome.

For more about David Hardy’s work

visit www.astroart.org.

Amateur SceneMemories of working alongside Sir Patrick

Ian Crawford

takes on SPA

Presidency.

Jeff Stevens becomes the new

SPA Webmaster and Michael

Hezzlewood is appointed as

Planetary Section Director.

Dusko Novakovic takes on role

as Light Pollution Liaison Officer.

April: Ian Morison’s first

Telescope Topics pages.

July: Meetings now held at the

SOAS Khalili Lecture Theatre.

SPA

visits to

the

University of London

Observatory (Feb) and

Jodrell Bank (Jun).

March: 2nd SPA

Convention, held at the

Institute of Astronomy,

Cambridge. Another

big success, it was

visited by the Astronomer Royal, Professor Sir Martin Rees.

Emily Baldwin becomes editor of Prime Space.

PETER WADE’S roundup oflocal astronomical society

news and events

David and

Sir Patrick,

shown by

the artist on

the surface

of Saturn’s

biggest

moon Titan

in the 1970s

(left) and in

the (real)

study of

Farthings,

Selsey, in

2003.

Images:

David A.

Hardy.

20072006 Mandy Bailey, the new SPA Publicity Officer. Lord Rees and

Robin Scagell.



THESE days, a cloudy

night doesn’t mean you

can’t do any astronomy. For

starters, you can look for

messages from aliens

through SETI@home. This

citizen science project has

involved some hundred

thousand computers

worldwide and has inspired

other projects including

Einstein@home and

asteroids@home as well as

ones like malariacontrol.net

completely outside the field

of astronomy.

Google Earth looks up as

well as down (click on the

Saturn icon on the toolbar)

and opens up sky maps as

well as maps of objects in the

sky such as Mars and the

Moon. Mobile devices will

additionally give you a sky

view in the direction you are

looking.

Galaxy Zoo involves you in

the classification of galaxies

on images from the Sloan

Digital Sky Survey. Some 40

million galaxies have been

classified and along the way

the project has thrown up

odd objects such as Hanny’s

Voorwerp, a strange filament

apparently associated with a

galaxy, and, more recently,

new objects such as the so-

called ‘green peas’.

Cloud spotting

on cloudy nights

may not seem an

inspiring activity

unless the clouds

are ones of gas

in the Milky

Way. Here

projects are

concerned with

identifying the

edges of gas

bubbles.

Add to this the

use of remote

telescopes and images from

space such as from SOHO,

cloudy nights become lively

nights for astronomy where

you can use existing

packages, participate in

mass projects or look at the

research findings of others.

Amateur Scene

2007, continued ...

Young Stargazers Section is

launched, with Emily Baldwin

its ‘Chief Stargazer’.

p14

Cloudy nights can be lively nights

SPA participates in IAU’s

International Year of

Astronomy, themed on 400th anniversary

of the telescope’s first astronomical use.

Members’ Open Telescope evenings held

around UK, mainly on the dates of Spring

and Autumn MoonWatch, and the Jupiter

and Schools MoonWatch. SPA also runs

Telescopes for Schools project and

produces an associated DVD-video.

March: 3rd SPA Convention in

Cambridge. Another excellent event.

Jeff Stevens takes on Occultation Section.

Above: SETI@home began in

May 1999. Based on the

Drake Equation a conclusive

alien signal is likely to be

detected before 2025.

Below: Zoom-in of the Apollo

16 Descartes landing site in

Google Earth, Moon view.

2009New President,

Helen Walker.David

Scanlan

takes on the Variable

Star Section.

July: Prime Space

incorporated into

Young Stargazers’

section in PA.

Dave Pearson briefly

takes on the role of

SPA Webmaster but is

replaced by Kevin

Brown later in the year.

2008

Emily

Baldwin.



Amateur Scene

THE British Astronomical

Association has established The

Sir Patrick Moore Prize to be

awarded annually in recognition of

groups or individuals who have

encouraged a public interest in

astronomy, contributed to our

understanding of the history of

astronomy, carried out collaborative

work, encouraged participation in

observation by young people or, for

younger people themselves, done

outstanding observational work.

BRECKLAND Astronomical

Society held their autumn star

party under the dark skies of Haw

Wood Caravan Park in Norfolk in

September. The park holds a Dark

Sky Discovery Site award—Milky

Way class—from the Science and

Technology Facilities Council.

MEMBERS of Liverpool

Astronomical Society took

their solar telescopes along to an

open day at Wharncliffe Allotments

on 8 June. The Sun obliged,

allowing viewing in H-alpha light

and in white light through mylar

filters. Meanwhile Liverpool AS

meetings continue with Dr Mark

Hadley on the use of chirality in

the search for extra-terrestrial life

(15 November) and members’ talks

on 13 December. The meetings

start at 7pm in the Quaker Meeting

House, School Lane, Liverpool.

MEETINGS of Orwell

Astronomical Society’s

Newbourne Observing Group

continue in Newbourne Village Hall

from 7pm on 11 and 28 November

and 9 and 19 December. The

society’s annual open weekend at

the Orwell Park Observatory will

meanwhile be held on 22 and 23

November from 7.30pm.

Out and about

PA is redesigned and moves from

quarterly to bimonthly publication; it

now includes section reports.

Martin Morgan-Taylor

redesigns SPA

website.

March: 4th SPA

Convention in

Cambridge. Another

great event.

Mell Jeffery takes

post as Occultation

Section Director.

IF anyone’s bought a security light recently,

they’ll probably find a leaflet in the packaging

entitled Getting Light Right—simple tips to get

your floodlight working best for you and the

environment. The leaflet is produced by the

Department for Environment, Food and Rural

Affairs alongside the Campaign to Protect Rural

England, the

Institution of Lighting

Professionals and the

Campaign for Dark

Skies, and is the

latest step in a

campaign spanning

almost 25 years to reduce light pollution.

Over-bright domestic lights are one of the most

annoying sources of unnecessary illumination.

Under its heading Be considerate of others, the

leaflet points out the importance of choosing the

right bulb for the job. A 150W bulb is

recommended as appropriate for lighting small

areas and less wasteful of both energy and money.

The leaflet also warns against intrusive lighting

affecting neighbours and points out that fines may

be imposed if such lighting is judged to constitute a

statutory artificial light nuisance by the local

authority.

Fight night blight,

get light right

20112009,

continued ...

Peter Grego

takes on writing

Deep Sky

Notes after

death of Dave

Fletcher, and

Jerry Stone

takes over from

Dave Tipper as

writer of Space

Exploration

pages in PA.

John Zarnecki, new

SPA President 2010.

Helen Walker

becomes

Treasurer, taking over from

Leslie Green who had done

the job since 1967.

New Planetary Section

Director Andrew Robertson

and Martin Morgan-Taylor

becomes Light Pollution

Liaison Officer.

April: Dale Holt becomes

writer of Deep Sky Notes.

November:The final SPA News Circular.

2010

Brian Cox becomes honourary

member, in good

company with

honourary member

Brian May.



SPA’s 60th

anniversary.

A range of

special days are

organised

around the UK

during the year.

Wonderful tribute

paid to Sir Patrick Moore at January meeting.

David A. Hardy designs special 60th

anniversary cover for Mar-Apr issue of PA.

2013

Last year I reported some of the

research Kevin Kilburn had done on

the early rocket pioneers in the North

West of England and, in particular, Eric

Burgess (Amateur Scene, Popular

Astronomy September/October 2012).

The first flights of these rocketeers is

now recorded in a plaque set up at

Clayton Vale by Manchester and

Salford Astronomical Societies along

with the British Interplanetary Society

(BIS). Further background has been

provided by Gurbir Singh writing in the

BIS magazine Spaceflight.

Eric Burgess (pictured at

right) had formed the

Manchester Interplanetary

Society in 1936. The following

year the society was set for

the test launch of thirteen

experimental rockets, all

designed and made by the

members themselves some of

whom, photographs reveal,

were still in short trousers.

The experiments were very

hazardous with one of the

rockets actually exploding

and causing injury to

three of the pioneers,

one of whom required

hospital treatment.

The test flights

attracted

considerable

attention, not least

because the

participants were

summoned to appear

in court under the

1875 Explosives Act!

As well as the

Manchester group,

other rocket groups

are known to have

formed in Hastings,

the Midlands, Leeds

and Paisley during

the 1930s.

Gurbir Singh notes

an interesting

connection between

Eric Burgess and

Salford AS. While

living in Macclesfield

in the 1950s Burgess had used a 45 cm

reflector at Jodrell Bank whose purpose

was to examine the optical counterparts

of radio sources detected by the famous

radio telescope then still under

construction.

In the 1970s the telescope and its

dome found a new home under the

curatorship of Salford AS and during

the late 1970s Gurbir himself, as a new

member of Salford AS, looked through

this very telescope, one that Burgess

had used 20 years earlier, shortly before

his move to the USA.

Explosive start for

northwest rocketeers

Clayton Vale, 27 March 1937. Pioneer rocketeers (left to

right) Eric Burgess, Bill Heeley, Trevor Cusack, Harry

Turner. Image: Philip Turner.

Host societies

welcome BAA

BRISTOL Astronomical Society

hosted a weekend meeting of the

British Astronomical Association (BAA),

The new, the old and the ancient, in

September. Bristol AS recently

celebrated its 70th anniversary. It has

over 120 members and gathers weekly

at Bristol Grammar School to hear

guest speakers or for informal club

nights. The society observatory is open

to the public on Saturday evenings.

Details of Bristol AS can be found at

www.bristolastrosoc.org.uk

This splendid cake, made to mark the

Bristol AS’ 70th birthday, was presented

at the society’s anniversary dinner on

February 2013.

IN October a BAA Back to Basics

workshop was hosted by East Sussex

Astronomical Society. The society has

grown rapidly and currently meets at

St Mary’s School, Bexhill. East Sussex

AS has its own observatory and has a

lively programme of outreach activities

including solar observing on the

seafront at De La Warr Pavilion (shown

below, with some expectant observers).

Burgess.

Amateur Scene

Alan Clitherow becomes Planetary

Section Director.

George Ford and Ezzy Pearson take on Young

Stargazers pages, and Helen Walker starts at Space

Exploration.

October: Special meeting at South Downs Planetarium.

Computing Advisory Service disbanded. Graham

Bowden-Peters had been in post since its inception in

1993. Tony Markham takes over from Alastair McBeath

at Meteor Section

December: Sir Patrick Moore, one of the founder

members of the society, dies.

20122011,

continued ...

May: After

more than a

decade, Alan

Longstaff

retires from

writing

AstroNews.

August: Special

SPA meeting at

the Greenwich

Planetarium.

Derek Ward-Thompson, the

new SPA President 2012.

Pla

tinum

Jubile

e:

2023



WATER is a substance that is easily takenfor granted. There is a lot of it about—

the oceans cover about 70 percent of thesurface of planet Earth.

The importance of water to life on Earth isalso something else we take for granted.Although it is common to refer to life onEarth as being carbon-based, it might bemore accurate to think of it aswater-based. A typical human bodycomprises about 60-70 percent water butonly 18 percent of carbon. Although ahealthy human being can survive for about amonth without carbon-based food, at bestwe can last a week without water.

Three states of matterIt should come as no surprise, therefore, thatthe habitable zone around a star is definedas the region where liquid water can exist.To a physical chemist, however, the mostinteresting fact about water on this planet isnot that it exists as a liquid, but that it can,and does, exist in all three states of matter—solid, liquid and gas.

Experiments on the formation of organicmolecules have demonstrated theimportance of liquid phase and gas phasewater for the prebiotic syntheses of proteins,whereas the existence of solid and liquidwater may have been more important for theorigin of nucleic acids. So what are theseproperties of water in all three phases andhow have experiments demonstrated theimportance of all three phases?

Most people are familiar with the solid toliquid transition of water. When ice iswarmed above 0ºC—whether it is in theform of snow, or ice cubes in a cold drink—it melts. Equally familiar, if we heat water to100ºC, for example in a saucepan or kettle,it boils, changing from a liquid to a gaseousstate. Scientifically we would say that thethermodynamically stable form of water,below 0ºC, is a solid; between 0 and 100ºCit is a liquid, and above 100ºC it is a gas.

Water can transition from the liquid to thegas phase below 100ºC. This is the familiarprocess of evaporation, typically seen in thedrying of puddles or of washing on a line.There is a well-defined relationship, or

equilibrium, between temperatureand pressure, and the amount ofwater that exists in theatmosphere below 100ºC,the boiling point.Formally this is called thevapour pressure,

although it isbetter known as thehumidity of the air.

Water molecules canalso move directly from the solidphase to the gas phase by the process ofsublimation. The amount of water that canexist in the gas phase in equilibrium with ice,however, is very small. At very lowtemperatures this amount is vanishinglysmall, which explains why icycomets and icy moons can existin space and do not simplysublime. At a temperatureof -200ºC, an icy bodythe size of Enceladus (thesixth largest satellite ofSaturn, 1,584 km across) will eventuallydisappear by sublimation into space, but theprocess would take something of the orderof six billion years.

Distribution of waterThe existence of water in the liquid and gasphase is important for the distribution ofwater across a planet whose surface is amixture of rock and water. Although there isno doubt that sustainable life could existsolely in the oceans, the colonisation of landby water-based life forms is only possible ifthere is a mechanism that distributes waterfrom the oceanic reservoirs to the dry land.

On Earth this is achieved via the water orhydrologic cycle. In a process driven by heatfrom the Sun, liquid water in the oceansevaporates into the atmosphere, or gasphase. Rising currents of warm air carry thewater vapour to the higher, cooler parts ofthe atmosphere where it condenses backinto liquid water in the form of clouds. Rainfrom the clouds spreads the water cross theland masses, where under the influence of

gravityit runs off and returns to the oceans. Thusland-based life is provided with a constantsupply of water.

Variations in temperature and pressureacross the Earth lead to variability in theamount of water that is present in theatmosphere. In warm tropical areas theamount of water vapour may be close to themaximum, a maximum defined as 100percent relative humidity. In contrast to this,in the dry valleys of the Antarctic, there isvirtually no water in the atmosphere. Theaverage relative humidity at the South Pole is0.03 percent, much drier than any desert.

These differences in temperature andhumidity have led to the evolution of a widevariety of life forms. Such a variety of livingorganisms may be essential for the long termsurvival of life upon a rocky planet. Asclimate changes, or in the event of extra-terrestrial disaster such as the Chicxulubimpact 65 million years ago, the loss of onelife form can be compensated for by thegrowth of other populations.

The GoldilocksZone, refinedThe GoldilocksZone, refinedThe fact that water exists in solid, liquid and gas formon planet Earth was essential to the development oflife on Earth, and remains vitally important to lifetoday. TONY AUFFRET plumbs the subject.



Climate and diversityWhen looking for planets that are not only

within a habitable zone around a star, butare likely to support life, then an axial tiltwhich introduces seasonal climate changesmay be a valuable clue. Perhaps, as in thecase of Earth, the presence of a largesatellite that stabilises the tilt may increasethe likelihood of life being present on thatplanet.

The equilibrium between liquid water andgaseous water, therefore, is important notonly for the support of life across the surfaceof a planet but also for the generation ofdiversity. When considering the survival oflife over long periods of time, such diversitymay be an important consideration. Butwhat of the solid liquid equilibrium—thefamiliar ice and water transformation—whatrole does that play? Life in a cold climateneeds particular adaptations, but perhapslife in any climate zone requires appropriatemodification, brought about by the processof evolution.

Whereas a cold climate may presentspecial risks and challenges to life, and theArctic and Antarctic regions of the Earth aresparsely populated, freezing itself is acompletely different challenge. Put almostany terrestrial life form—bacterial, fungal,plant or animal—in a freezer and the resultis almost invariably fatal. There areexceptions, the presence of some veryspecialised and rare adaptations, or somevery particular pre-treatments, both of whichrequire a period of acclimatisation. Ingeneral, however, freezing kills. So how canthis process be of value in defining thehabitable zone around a star?

Defining the habitable zoneTo answer that question, and also why theliquid/gas phase transition of water isimportant, we have to consider the buildingblocks of life and how they came intoexistence. Ask anyone about the origin of lifeand the most likely image to come to mindis a primordial landscape with a lake and avolcano erupting in the background, withlightning flashing across a heavy sky. Inmany ways this scenario is derived from a

classic experiment carried out by StanleyMiller and Harold Urey at the University ofChicago in 1952. In this experiment a flaskof water was boiled and the steam passedinto a second flask containing an oxygen-free atmosphere containing hydrogen,methane and ammonia. Although we take itfor granted that oxygen is present in ouratmosphere, it is a very reactive molecule. Inthe absence of photosynthetic life forms,which generate gaseous oxygen, all theoxygen would be locked up in the form ofoxides, including water and mineral oxides.In the Miller experiment, sparks were passedthrough the gaseous mixture to simulatelightning and the ‘atmosphere’ was thenpassed through a condenser to trap thewater as a liquid, which could then beevaporated to continue what was asimulation of a hydrologic cycle.

After about a week of recirculating thewater, Miller and Urey analysed thecondensed water and found that 10-15

percent of the carbon from the atmospherehad been trapped as organic molecules.Included in this mixture of organic moleculeswere eleven types of amino acid. The waterhad been changed into a soup of organicmolecules, supporting the primordial orprimeval soup theories that had earlier beensuggested by Alexander Oparin and J.B.S.Haldane. What Miller had established wasthe importance of liquid and gas phasewater in abiogenesis.

In a different and much longer termexperiment Miller investigated the role of theliquid/solid phase (water/ice) transformationof water in the origin of organic materials. Inan extraordinary experiment lasting morethan 25 years, Miller froze a solution ofammonia and cyanide to -78ºC.

Chemistry at low temperatureConventional wisdom says that at such a lowtemperature, very little chemistry, if any, may beexpected to take place. Miller found that,

The Three Statesof MatterOn the Earth, moleculescan exist in three states,or as scientists wouldcall them, phases—thesolid, liquid and gas phases.

The solid phase is the most stable,lowest energy state. In the solid phasemolecules are ordered in fixed, repeated,spatial arrangements, they form a crystal.Ice is the solid, crystal, phase of water.

If we add energy, typically heat, to a crystalit will melt and form the next phase, theliquid phase. Liquids flow because althoughattractive forces keep themolecules closetogether, the moleculeshave too much

energy toremain

in fixed positions. This is the most familiarphase of water on the Earth.

Adding even more energy will overcomethe attractive forces and the liquid will boil toform a gas, steam in the case of water. Theenergy required to change from a liquid toa gas is much greater than that need tochange a solid into a liquid.

It is possible to go directly from a solidto a gas—a process called sublimation,or from a liquid to a gas without boiling

by the process of evaporation. When agas turns to a liquid, typically by cooling, itis said to condense, and a liquid turns to asolid by the process of crystallisation. Thisprocess is also called solidification, or in thespecial case of water, freezing.

The 1952 Miller-Urey experiment.



The buildingblocks of lifeEven the simplest living organisms area very complex mixture of biochemicals,molecules both large and small. The mostcomplex molecules of life are large polymerseither of nucleic acids, proteins orcarbohydrates. Viruses, the simplest knownorganisms, consist essentially of a long chainof nucleic acid wrapped in a protein coat. Asthey are incapable of replicating themselveswithout hijacking the cellular mechanisms ofother organisms, opinions differ as to whetherthey can be classified as living.

In general, nucleic aids andproteins are called thebuilding blocks of life. Theinformation required for life isstored in the DNA molecule,

an extremely long double helixof two complementary strands of DNA.

Each strand is built from only four buildingblocks, the nucleic acid bases generallyknown by their abbreviations A, T, G, and C.The sequence of the building blocks containsthe code for life.

Proteins are very versatile molecules, andcan be structural, bone is mineralised protein,functional, as in muscle, or catalytic, as inenzymes which control the chemical reactionsof life. The building blocks of proteins are

amino acids which are linked head to tail infolded chains. Terrestrial life, uses twentyamino acids to construct its proteins. Thesequence of amino acids in a protein isdetermined by the sequence of the bases inthe DNA code, and it is the sequence of theamino acids that determine the function of theprotein. Very few of the possible proteinstructures actually exist. If we take a proteincomprising a sequence of 100 amino acids,and that would be classed as a small protein,and were to construct one molecule of everypossible sequence, the resultant mass wouldweigh about 2 x 10105 kg. This is significantlymore than the mass of the known universewhich is estimated to be between 3 to 8 x1052 kg.

despite the low temperature, the mixture notonly contained some amino acids, but alsonucleobases—the building blocks of RNA andDNA. Other scientists, notably US-basedLeslie Orgel and German-based ChristofBiebricher showed that not only could shortchains of RNA molecules assemble underfreezing conditions, but that if the system wasprimed with a strand of RNA, acomplementary strand was synthesised againstthis primer—effectively demonstrating thatnucleic acid replication, an essential featureand prerequisite of terrestrial life, was possible.

Like Miller’s initial study, many of theseexperiments were left for long periods of time,as the expectation is that chemical reactionsslow down as the temperature drops. Thispresents a paradox, and one which initiallyraised scepticism over the results, why do thesereactions proceed faster at lowertemperatures? The answer lies in the freezingprocess, the liquid/solid transformation ofwater which has two important aspects. Firstly,an ice crystal, unlike many other crystals(notably gemstones), does not allow anyimpurities within its crystal lattice—it is puresolid water.

Secondly, when an aqueous solution freezesit does not totally solidify. Pure solid water iceforms but some of the water remains unfrozenand this unfrozen water is in the form of asolution which contains all the solutes. Ineffect, this residual solution is much moreconcentrated than the original solution. Theamount of ice that forms, and the resultantconcentration of the residual solution, iscontrolled by the temperature, and in terms ofphysical chemistry may be mapped as a phasediagram. As the temperature is lowered andthe residual solution becomes moreconcentrated, eventually there comes a pointat which there is too little water to dissolve thesolute. At this point (the eutectic point) thesolute comes out of solution and theremaining water freezes.

For a solution of sodium chloride (salt) theeutectic temperature is -21ºC when theconcentration of salt reaches 4 moles per litre.Seawater contains about 0.5 moles per litre ofsodium chloride, which, therefore can be

concentrated eight times by freezing. Solutionsof other salts may have even lower eutectictemperatures.

The effect of freeze concentration,sometimes called eutectic concentration, isthat molecules are squeezed into a smallvolume of liquid, increasing the chance ofreactions occurring through molecularcollisions. In 1986, Cambridge-based scientistFelix Franks demonstrated a 60 fold increasein the rate of oxidation of ascorbic acid uponfreezing to temperatures close to the ascorbicacid solution eutectic temperature of -18ºC.Increases in chemical reaction rates of thisorder of magnitude, however, may beconservative estimates. The important point isthat many, if not most materials, do notcrystallise from frozen solutions in a classictextbook manner, but may be cooled to lowertemperatures, greater degrees ofconcentration and a greater chance ofchemical reaction.

The mechanism of crystallisation is complexand at these low temperatures, crystals maysimply fail to form or to grow. A frozen solutionof sugar (sucrose), for example, does not showsugar crystallisation at -10ºC, the eutectictemperature, but continues to concentrate untilit becomes so viscous that, at -32ºC, it is assolid as glass. Once this point, the glasstransition temperature, is reached, there is nofurther change or concentration on loweringtemperature. The addition of salt (sodiumchloride) significantly reduces the temperatureat which this glass viscosity is reached andunfrozen, highly concentrated solutions ofsugar and salt can exist at -90ºC, the coldesttemperature recorded on Earth. Rather like thevariation in eutectic temperatures, frozensolutions of other materials have different glasstransition temperatures. A solution of glucosehas a glass transition temperature of -43ºC,whereas a frozen solution of zinc chloridevitrifies at -88ºC. Water itself will turn to a glassat -138ºC, although very special techniquesare required to prevent it freezing long beforethat temperature can be reached.

Simple organic molecules, frozen inseawater, may therefore exist as highlyconcentrated solutions, with concomitant

increases in chemical reaction rates, at verylow temperature, explaining the importance offreezing in the abiotic generation of biologicalmolecules.

In searching for life on other planetsidentifying the habitable zone, the zone whereliquid water can exist is an important step inincreasing the probability of success. Whatdifferentiates the Earth from other planets inthe solar system is that water can exist in allthree states of matter. The importance of thisdifferentiation has been demonstrated by ourcurrent understanding of how the molecules oflife may have been generated in an abioticenvironment. Redefining the Goldilocks Zone,narrowing down the search to find zones orplanets where water can exist in all three statesof matter may significantly increase thechances of success in the search for extra-terrestrial life. If we then add an additionalrefinement that climatic variation leads to adiversity of life forms, increasing the chances oflong term life despite inevitable naturaldisasters, then planets with an axial tilt and astabilising moon should be prime targets in thesearch.

Organic chemicals. Molecules that containcarbon, e.g. methane, amino acids, sugars.

Abiogenesis. The theory that life can arisestarting with the combination of inanimatematter.

Crystal lattice. The regular three-dimensionalrepeating pattern of atoms or molecules thatmake up a crystal.

DNA. Deoxyribonucleic acid, the chemicaldatabank of life on Earth. The sequence of 4bases in this linear polymeric molecule, theDNA code, stores the information necessaryfor life.

RNA. Ribonucleic acid. A linear polymer ofnucleotides that acts as the messengerbetween the DNA databank and the cell’schemical synthesis machinery.

Tony Auffret is runs taPrime Consulting and isthe UK Director of the BioUpdate Foundation.His scientific background encompasses thebiochemistry of protein evolution and thephysical chemistry of biopreservation.

November-December 2013p18 Popular Astronomy www.popastro.com


Mars before the flyby of Mariner 4When I became fascinated by astronomy in1951 at the age of ten Mars had long beenthought to bear life. This enchanting beliefwas held by many professional astronomersand by the great majority of the generalpublic—that is, until the flyby of Mars byMariner 4 in 1965.

Mars is our planetary neighbour goingoutward from the Sun. Most of the late 19thCentury ‘vital statistics’ of Mars differ littlefrom the present values (see table below),though they are now known to greaterprecision.

The ‘canals’ of MarsMartian surface features were first recordedin the middle of the 17th Century, but I’ll skipto 1877, when the infamous history of thecanals of Mars began.

The 1877 opposition occurred whenMars, in its modestly eccentric orbit, wasnear perihelion, ‘merely’ 56 millionkilometres from Earth. During that perihelicopposition many astronomers madedrawings of Mars, but it was the those madeby the 42 year old Italian astronomer

Giovanni Virginio Schiaparelli that drew alot of attention. He used the 22 cm (8.6-inch) aperture Merz refractor that had beeninstalled at Brera Observatory, Milan, in1862—too late for the previous perihelicopposition in 1860. As well as refining themaps of the previously known features, hedrew narrow linear features that he called‘canali’, Italian for ‘channels’.

A few English-speaking astronomers madethe all too easy transliteration of ‘canali’ into‘canals’, thus implying their construction byi n t e l l i g e n tbeings. Thea s s u m e dpurpose of the‘canals’ wasto eke out thewater supplyof a dry world,as indicatedby thew idespreadred deserts.What wasvisible, it wassaid, was not

the water in the canals but strips ofvegetation running along them.

The main proponents of intelligentMartians were the American astronomersPercival Lowell (1855-1916) and hiscontemporary William Pickering (1858-1938). Lowell came from a wealthy Bostonfamily. He graduated from Harvard

‘Vital statistics’ of Mars and Earth compared. All Solar Systemplanets have ages of 4.6 billion years.

Mars, beforethe Space AgeMars, beforethe Space AgeProfessor BARRIE W. JONES takes a look at ourknowledge of the Red Planet prior to the advent ofspace probes. While many mysteries of Mars havesince been explained by robotic exploration, many of theplanet’s features and phenomena remain enigmatic.

Mars in opposition atperihelion. Perihelic

oppositons arewhen Mars is

close toperihelion,

and are spaced by

either 15 or17 years.

Mars in opposition

at perihelion.

Graphic: BWJ / PTG.

Earthperihelion

Mars, asseen by space

probes and the human eye. Graphic: PG.

Giovanni Schiaparelli,depicted on a 2010

Italian postage stamp.



University in 1876 with a distinction in mathematics, and in the 1880stravelled extensively in the Far East. He returned to the UnitedStates in 1893, determined to study astronomy, particularly Mars.

Lowell used his wealth and influence to construct anastronomical observatory in Flagstaff, Arizona, on a hill risingto an altitude 2,210 metres (7,250 feet)—an elevation thatbecame known as Mars Hill. It is an excellent site, with verygood seeing and few cloudy nights. Building started in 1894with Pickering helping the construction. The main telescopehas a 62 cm (24-inch) objective lens by Alvan Clark & Sons.Lowell lived with his wife in a house on Mars Hill where hismausoleum is also sited.

Lowell adopted the ‘canal’ interpretation of Schiaparelli’s‘canali’ and he spent 15 years observing and mapping them.However, most astronomers could not see these features, soLowell’s views had very little currency in the professional astronomyof the time. Right: Mars by Lowell (south at the top).

During the perihelicopposition of 1909, the

1.56-metre (60-inch)reflector on MountWilson in southernCalifornia wasused to examineMars. No canalscould be seen,leading to theconsensus thatLowell had simply

m i s i n t e r p r e t edirregular geological

features that wereprobably the result of

erosion. The flybys of Mariners 4, 6,

and 7 in the 1960s, and theMariner 9 orbiter in 1972 finally put the

kybosh on Martian canals. They are evidence of intelligence, butit’s at the eyepiece end of the telescope.

So what was Lowell seeing? Several explanations have been putforward. One is that the viewing of approximately co-linear spotsand streaks at the limit of visibility leads to the brain tidying themup. But missions to Mars have seen no such features at the greatmajority of places where Lowell’s ‘canals’ were located. It is nowwidely believed that his ‘canals’ were an optical illusion. Onerecent view is based on Lowell’s habit of stopping down thetwenty-four inch objective lens to a substantially smaller aperture.This can result in an image contaminated by retinal shadows ofthe eye’s blood vessels.

Schiaparelli’s1877 map ofMars (southat top). FromOservazioniAstronomichee FisicheSull’asse diRotazione eSullaTopografiadel PianetaMarte (1878).

Fantastic fictionBut even though astronomers have longrejected Martian canals, authors offiction have clung on to the belief. Thefirst of these is H G Wells, whosemagnificent The War of the Worlds waspublished in 1898. Thereafter followeda steady flow of science fiction withcanals on Mars, including Red Planet(1949) by Robert A Heinlein and TheMartian Chronicles (1950) by RayBradbury. Great fun!Martians on Earth. From the first edition

of Wells’ The War of the Worlds.

Lowell at the Clarkrefractor, Mars Hill.Percival Lowell (left) and William Henry Pickering, both pictured around 1909.



Albedo features andthe atmosphere It was well established by the19th Century that there arethree types of albedo featurevisible from Earth: the brightorange-red areas, which arethe most extensive of thethree; the dark areas, whichare the next most extensive;and the white polar caps, themost variable in extent. ThatMars has some sort ofatmosphere was indicated, forexample, by dust storms thatobscured albedo features,sometimes planet-wide.

Rather than go through in historical orderevery advance in our knowledge of Mars, I’llconcentrate instead on the picture justbefore 15 July 1965 when the NASAspacecraft Mariner 4 flew past Mars’southern hemisphere at a distance of only9,800 km.

The bright orange red areasThe bright orange areas had long beenconsidered to be deserts of sand and dust,The coloration of the areas was assumed bymany to be due to ferric oxide (‘rust’) Fe2O3.Audouin Dollfus (1924-2010) conductedspectrometry from a stratospheric balloon inwhich he flew and showed that indeed ferricoxide accounted for the colour.

The dust raised by winds in the thinatmosphere were held to cause theoccasional local or global obscuration ofthe Martian surface.

The dark areasThe dark areas were seen to change inshape, extent, and contrast, some of thechanges being seasonal. By 1892 mostastronomers thought that they were not seas.Powerful evidence for this conclusion is thelack of a bright spot that extended bodies ofwater exhibit when illuminated by the Sunand viewed from above. This spot is thereflected image of the Sun. Also, the darkareas exhibit the un-sea-like behaviour offaint structures that varied seasonally.

Most astronomers thought that the darkareas were vegetation, changing in extentand contrast in response to the seasons. Afew astronomers thought that they consistedof minerals, the seasonal changes the resultof the dampening of hygroscopic mineralsby water vapour released from the summerpolar cap.

The American astronomer DeanMcLaughlin (1901-1965) was closer to thetruth in his belief that the dark areasconsisted of volcanic ash placed in semi-permanent patterns by the prevailing winds.

The popular view among the wider publicwas the vegetation model. After all, this wasin accord with the hope that Mars wasinhabited.

The polar capsThe polar caps exhibit changesin extent in accord with theseasons, smaller in summer,larger in winter. They werethought to consist of water iceand snow. The caps providedfurther evidence for anatmosphere, without which thevolatile polar caps would belost to space throughsublimation.

The atmosphereThe dust storms and the whiteclouds (see below) was furtherevidence for an atmosphere.That the atmosphere is thin was indicated bythe large diurnal swings in the temperatureof the Martian surface.

Analyses of solar radiation scattered byMars plus wobbly assumptions led toestimates of the mean surface pressure in therange 80-120 millibars, significantly lessthan the Earth’s 1013 millibars. The columnmasses are more similar because of Mars’slower surface gravity, 3.7 m/s2 versus 9.78m/s2, giving column masses of 0.21-0.34for Mars and 1.03 for the Earth, in units of10 000 kg/m2.

The composition of the Martianatmosphere was determined by spectrometryfrom the Earth’s surface. Suchmeasurements are bedeviled by the Earth’smuch more massive atmosphere. Dollfusmade measurements at the Pic du MidiObservatory at an altitude of 2,877 metresin the Pyrenees. Greater altitude reducedfurther the effect of the Earth’s atmosphere,so he ascended by balloon into thestratosphere to make further measurements.

The outcome of his and others’measurements, predominantly at infraredwavelengths, was that the atmosphere ofMars contained a few millibars of carbondioxide (CO2) and a few hundredths of amillibar of water vapour. Oxygen (O2) was

undetectable, but homonuclear diatomicmolecules have very weak spectralsignatures in the infrared. Also, there’s a lotof O2 in the Earth’s atmosphere that wouldeasily mask a Martian signal. The same istrue of nitrogen N2. But N2 was chosen tomake up nearly all of the 80-120 millibarspresumably because unlike O2 it does notrequire an extensive biosphere, and alsobecause nitrogen is an abundant elementthat, for example, comprises 77% of theEarth’s atmosphere.

The white clouds are usually sparse andshort-lived. The more extensive polar hoodin the winter hemisphere lasted for manyweeks. Both types were presumed to consistof tiny crystals of water ice. Small isolatedwhite clouds were thought to mark mountaintops, such as one called Nix Olympica.There were also yellow clouds, mentionedearlier, extensive, sometimes to the extent ofcovering the whole planet and lasting fromdays to weeks. They were surely fine dustraised from the deserts by strong winds.Finally, there are high altitude thin hazes,called blue clouds, presumed to consist oftiny crystals of water ice, perhaps carbondioxide crystals too (dry ice).

So, how does the pre-Space Age picture ofMars measure up to our current knowledge?

Mars, August 1956, photographed byR.B. Leighton (north at top).

Right: Audouin Dollfus (at anadvanced age) about to ascend

by balloon to the stratosphere.

Pic du Midi Observatory,altitude 2,877 metres in

the French Pyrenees.



Martian topographyThere was little evidence of Martiantopography before the Space Age. Isolatedwhite clouds were thought to mark mountaintops, such as Nix Olympica. As this article isabout Mars before the Space Age, I presentonly a brief summary of what we now knowabout the Martian surface.

The many images from flybys, orbiters, andlanders, show that the Martian surfaceconsists of two quite different hemispheres,the ragged boundary being inclined atabout 30° to the equator. The southerlysurface is peppered with impact craters,indicating a surface of age greater thanthree billion years. There are large cratersand small craters, but none very small—these have been weathered away. Abundantin this hemisphere are channels of variouswidths, lengths, and complexity, widelythought to have been carved by liquid watermore than three billion years ago, early inMars’s 4.6 billion year history.

The northerly surface is mostly fairly flat,with few impact craters, indicating youth. Butit does have the most dramatic topography.This includes a huge rift valley system, VallesMarineris, about 4,000 km long, up toseveral hundred kilometres wide and up toeight kilometres deep.

There are two broad domes, the largerbeing the Tharsis region, which bearsseveral shield volcanoes (from theirresemblance to a warrior’s shield). Thelargest of these is Olympus Mons, the largestshield in the Solar System and possiblydormant rather than extinct. It is about 550km across and rises to 25 km above theadjacent plains. It is at the location of thepre-Space Age Nix Olympica.

Life on MarsBefore spacecraft started to arrive in 1965(Mariner 4) it was still considered a possibilitythat the dark areas were vegetation. From1965 this was thought unlikely.

Mars was thought tobe devoid of life.However, within a fewyears this pessimistic

view changed, with the discovery, notedabove, of ancient channels that seemed tohave been carved by flowing liquid water,and gulleys on the sides of impact cratersand channels indicating contemporaryoutbursts of liquid water presumably fromreservoirs at no great depth.

Then there is methane gas (CH4) detectedin the early years of the noughties from Earthand also by the Mars Express Orbiter. Eventhough the level is only a few parts perbillion, methane is destroyed so rapidly in theMartian atmosphere that a steady source isrequired. Whether this is geological, orsubsurface methane-generating microbes(methanogens), is still an open question.

The current view is that there might be tinyfossils of life that lived in the first billion yearsof Mars’ 4.6 billion year history, when Marswas warmer and wetter than today. In anynear-surface liquid water reservoirs there justmight be microbes and tiny multi-celledorganisms living today.

So that’s it. You’ve surely noticed that I’vesaid almost nothing about mechanisms.That’s for another article as long as this one.

*The bright area material is thought today to be an erosional product of the dark area material.

Left: Some Martian valleysappear to have beenproduced by flowing water.

Below: Olympus Mons, a shield volcano on the Tharsis Bulge inthe northern hemisphere, possibly extinct. It is about 600 km across

and rises to about 22 km above its surroundings. NASA / JPL.



Valles Marineris, in Mars’northern hemisphere, over

4,000 km long, 200 kmwide and up to 7 km deep.

It’s a stress fracture(NASA/JPL).



India’s first mission to the Red Planet

Space Exploration

THE Mangalayaan mission is

India’s first attempt to send a

satellite to Mars. Mangalayaan

(Hindi, meaning ‘Mars craft’)

launched on the Polar Satellite

Launch Vehicle from Andhra

Pradesh in India, and will reach

Mars in September 2014.

Mangalayan’s main aim is to

develop the technologies

necessary for an interplanetary

mission, including the manoeuvres

needed in Earth and Mars orbit

and deep space communications.

Some of the instruments have a

heritage from Chandrayaan-1, the

Indian lunar satellite, as does their

deep space network.

Mangalayaan will study the

Martian surface and atmosphere,

look for methane and measure the

deuterium-to-hydrogen ratio,

which helps to understand Mars’

water loss process.

Impression of Mangalayaan in

orbit around Mars as it passes

over Ganges Chasma, a huge

deep canyon (named after

India’s River Ganges) that is

thought to have been formed by

catastrophic flows of water and CO2 in the distant past.

Graphic by PG (based on Google Mars / NASA / ISRO).

MARS orbiters Mars Express,

Mars Odyssey, Mars

Reconnaissance Orbiter and Mars

Global Surveyor have been used to

identify the remains of

supervolcanoes on Mars.

Some supervolcanoes have been

identified on Earth—Glencoe and

Yellowstone Park, for example—

and now the Arabia Terra on Mars

is proposed as a candidate area for

supervolcanoes.

When a supervolcano erupts, the

whole area gets involved with

many eruptions, vents and

fissures, and afterwards the whole

landscape falls back into the void,

producing a large caldera.

The deep scars in the Hebes

Chasma were formed when the

Tharsis region swelled up with

magma in the first billion years of

Mars’ history.

Mars Express has shown that an

eight kilometre deep trough, 315

km long and 125 km wide, was

formed. It is near to Valles

Marineris and just as deep.

There is no other canyon quite

like Hebes Chasma; it has a flat-

topped mesa in the middle of the

canyon and a horseshoe-shaped

chunk has been taken out of one

side of the mesa, where material

slumped down onto the valley

floor.

The minerals detected in the

canyon have been formed in the

presence of water, suggesting that

the canyon might have been

flooded for some time in its

history.

Inset, right: Hebe Chasma,

imaged by the High Resolution

Stereo Camera (HRSC) on board

Mars Express. Image: ESA.

Hebe Chasma (immediately right

of this caption) lies to the north of

the Valles Marineris. Graphic by

PG (Google Mars / NASA).

Hebe Chasma—a

Martian supervolcano?


page 24-25 adlard spead:Layout 1 29/10/2013 17:32 Page 2

HELEN WALKER reports onastronautics, spaceflight and

space exploration

CURIOSITY has started to cause

a bit of a problem by failing to

detect methane on Mars!

Curiosity has been sampling the

atmosphere in Gale crater for a year

and has found no trace (less than 1.3

parts per billion by volume) of

methane. The Tuneable Laser

Spectrometer was used, and this

upper limit is around six times

lower than previous satellite and

Earth-based telescope estimates.

Mars Express

reported the detection

of methane several

years ago, in one

particular area and

maintained this was

a seasonal, geological

phenomenon.

Many people would

like methane to be

found, as evidence of

biological activity, but

it could be deposited by

comet or asteroid impacts

as well as by geological

activity. Hopefully, NASA’s

MAVEN, ESA’s Trace Gas Orbiter

or Mangalayaan will do better.

Mars news roundupMethanemystery

CURIOSITY has been more

successful with water detection,

finding a surprisingly large

amount—when it heated a small

pinch of soil from Rocknest in Gale

crater, there was around two percent

by weight of water in the sample,

much more than might be expected.

This means an astronaut could heat

around one cubic metre of soil and

get around ten litres of water—well

worth the effort. The sample also

gave off a lot of carbon dioxide, some

chlorine and also oxygen (similar to

that found by Phoenix in the High

Arctic region).

Another sign of the water-rich

ancient history of Mars comes from

one of the rocks identified early in

Curiosity’s mission. An unusually-

shaped pyramid rock was found (and

given the name Jake Maltijevic, after

a NASA engineer) and now the rock

has been identified as one not seen

on Mars before. It is a mugearite,

which means it is magma which has

crystalised in the presence of water,

and mugearite is found on islands

and rift zones on Earth.

Watersuccess

Above: Mars Express’ methane

measurements for Mars’ northern

summer. Image: ESA.


page 24-25 adlard spead:Layout 1 29/10/2013 17:32 Page 3

ESA’s Automated Transfer Vehicle

(ATV-3) has been and gone.

Weighing 20 tonnes at launch and

delivering essential supplies to the ISS,

ATV-3 (named Edoardo Amaldi) has re-

entered the atmosphere over the

southern Pacific Ocean and burned up.

All the manoeuvres from launch to re-

entry were done autonomously, but

with close surveillance from the ground.

While at the ISS the ATV was

powerful enough to move the ISS to a

higher orbit, or move out of the way of

space debris, and regularly adjusted the

altitude to compensate for the

atmospheric drag the ISS experiences.

ORBITAL’s Cygnus freighter arrived atthe ISS on its demonstration flight.

There had been software problems, but

a patch was uploaded while the

freighter floated 2,000 km away

from the ISS, and a week later

than planned, it was allowed to move in

close to the ISS. It was grabbed by the

robotic arm, and moved to the Harmony

module allowing the astronauts to

unload it. After unloading, Cygnus left

the ISS to be destroyed as it re-entered.

SPACEX uses the Falcon rocket to

supply the ISS using their Dragon

module, and they have now launched

their Falcon 9 rocket (from Vandenberg

Air Force Base) which has several

modifications to boost performance. One

special new development was an

attempt to avoid destroying the rocket

on re-entry. After the first stage

separated, it fired its three engines

again to slow its descent, and then fired

a fourth engine to slow the descent

further. It lost stability and so landed

harder than they had hoped, but this

was a promising start to a new phase of

rocketry.

THERE are well-developed plans by

a company called UrtheCast to put

two cameras on the Russian part of the

ISS, looking at Earth, a high definition

still camera and a medium resolution

video camera. The High Resolution

Camera, supplied by RAL Space and

EVC, has passed its first acceptance

test and has been shipped to Russia to

join the other camera for the next stage

of acceptance testing.

ON 9 July astronaut Luca

Parmitano became the first

Italian spacewalker. An hour and

a half into his EVA outside the

International Space Station (ISS),

Parmitano found his helmet

starting to fill with water1a

potentially disastrous situation.

He managed to return to the ISS

safely, although it did take two

people to get him out of the

spacesuit.

Extra tools have been shipped

to the ISS to help investigate the

problem.

When the Japanese astronaut

Koichi Wakata takes over as ISS

Commander in November, he will

have someone to talk to—

Kirobo, a 34 cm high,

Japanese-speaking robot

programmed to provide

emotional support. The biggest

challenge was to make the robot

compatible with operating in

space. It is an interesting idea to

help support people isolated over

long periods, and we all talk to

inanimate objects like computers

anyway (don’t we?).

If you would like to see

something completely

fascinating, catch the YouTube

video by Chris Hadfield, a

Canadian astronaut on the ISS,

who was asked by school-

children ‘what happens when you

wring out a wet towel in space?’.

I won’t spoil it for you, but it is

well worth watching.

PenetratorONCE upon a time, not so long ago,

there was a UK mission design

called Moonlite, which involved firing

penetrators to study the Moon’s surface

and interior, study moonquakes, and

act as relay stations for instruments

out of the direct line-of-sight to Earth.

This was shelved but the penetrator

idea is still alive and well, and being

tested on ice penetration in west

Wales.

Recently a 20 kg steel penetrator was

fired at a 10-tonne cube of ice, used to

simulate the surface of Jupiter’s moon

Europa. The penetrator hit the ice at

340 m/s and decelerated rapidly with a

huge plume of snow, but remained

intact. This is too late to be included in

the Juice mission, which will launch

for Europa in next decade but there are

plenty of other targets including Mars.

Getting even a short distance into the

ground or ice means sampling interior

material which has been shielded from

the harsh radiation environment. Since

the penetrators are relatively cheap, a

network of penetrators could deploy

sensors over a wide area and allow a

variety of terrains to be studied.

The instruments inside the

penetrator are protected by a

suspension system from a Torlon

polymer. There is work still needed to

provide electronics which can survive

the impact, and work at the very low

temperatures in the environments on

the Moon, Mars, Europa, Ganymede

and further afield.

Near-drowning in space

Looking distinctly trepidatious,

Luca Parmitano prepares for a

simulated spacewalk beneath

the waters of the Neutral

Buoyancy Laboratory near

NASA’s Johnson Space

Center, Texas. He is wearing

a training version of his

Extravehicular

Mobility Unit

spacesuit.

Image:

NASA /

ESA.

ISS activities

ATV-3, imaged from the ISS prior to

docking. Image: NASA / ESA.Space Exploration



YOU could be forgiven for not knowing the name John

Goodricke. He is not a widely publicised astronomer, even

among the astronomical community. However, his ground-

breaking work on variable stars ultimately led to us being able to

use Cepheid variable stars as ‘standard candles’ and thereby

allowing us to measure vast distances across the Universe.

Goodricke was born in the Netherlands but moved to England

when he was still a small child. As a youngster he contracted

scarlet fever which sadly led to him losing his hearing. His family

still wanted him to get a good education so sent him to a

specialised school, the Thomas Braidwood Academy, which

specialised in teaching deaf people. He later moved on to the

Warrington Academy in 1778.

When Goodricke had completed his studies he returned to his

family home in York and it was this move that brought him

deeper into the world of astronomy. He became friends with his

neighbour, Edward Pigott, whose father was a professional

astronomer and had his own observatory. Pigott had already

developed an interest in variable stars and actively encouraged

John to observe them too. After all, the more people making good

observations of particular stars the better, especially because so

few variable stars had been observed at that stage.

Goodricke studied two well-known stars: Delta Cephei and

Beta Persei, otherwise known as Algol the ‘Demon Star’. His

studies opened up a new pathway in astronomical observation

because he discovered that the magnitude (brightness) of both

these stars fluctuated over time.

On 12 November 1782 Goodricke wrote in his journal (every

good astronomer should keep a record of their observations):

“This night I looked at Beta Persei and was much amazed to find

its brightness altered... I observed it diligently for about an

hour... I hardly believed that it changed its brightness because I

never heard of any star varying so quickly in its brightness.”

Goodricke and Pigott calculated that the drop

in magnitude took place every 68 hours and 50

minutes (2.87 days) and the pair theorised that

this was due to a dark object orbiting the star.

We now know that Algol is orbited by another

star—an eclipsing binary system.

Goodricke was only 19 years old when he

presented his monumental findings to the Royal

Society, a phenomenal achievement and the

crowning glory of his life. Elected to the Royal

Society in 1786, just two weeks before he died

aged 21, he achieved much in his short life—

even more impressive considering the prejudice

that he would have faced at the time for being

deaf. Who knows what else he might have

accomplished?

So the next clear night, take a look at Algol or

Delta Cephei (charts can be found on the

Variable Star Section’s Web pages at

www.popastro.com/variablestar/ and spare a

thought for the brilliant John Goodricke, an

astronomer who demonstrated that a disability

cannot stop you from doing what you love.

Astro pages compiled byGEORGE FORD andELIZABETH PEARSON

Young StargazersFamous astronomers

John GoodrickeTamer of the ‘Demon Star’

By David Scanlan

Born: 17 September 1764, Groningen, Netherlands

Died: 20 April 1786, York, England

Famous for observations of variable star Algol

Algol (Beta Persei) goes

through a regular cycle

of brightness changes.

Every 2d 20h 49m, over

a period of around ten

hours, it drops from

magnitude +2.1 to

+3.4—changes easily

monitored with the

unaided eye. The cause

is a large, dim

companion orbiting the

bright primary star,

periodically eclipsing it.

1: Algol at minimum.

2: Algol brightest.

3: Slight drop in

brightness (not detectable

visually) as companion

moves behind primary.

Graphic: PG.



IN June 2011, my wife and I went on

holiday to Norway and spent two

weeks above the Arctic Circle (latitude

66½ degrees north). We saw the Sun

24 hours a day, apart from one night

when it was partially obscured by the

Moon!

In the far north the Sun never sets in

the summer. The Earth spins once on

its axis each day. During daytime your

part of the world faces the Sun and

when you’re facing away it’s night. The

Earth’s axis isn’t at right angles to its

orbit—it’s tilted by 23½ degrees, and

its position is fixed in space, always

pointing towards Polaris (the North

Star). So, the amount of daylight you

get depends upon how far north or

south you are from the equator (your

latitude).

At different times of year different

parts of the Earth will be angled

towards the Sun, meaning that the

length of a day depends upon the time

of year as well as your latitude. If it’s

mid-summer in the Northern

Hemisphere then the North Pole is

tipped towards the Sun. If you are

within the Arctic Circle at this time,

then the Sun won’t set below your

horizon—you’ll get 24 hours of sunlight

a day! The further north you go the

longer this lasts. From northern

Norway the Sun is above the horizon

from mid-May to mid-July.

While we were in Norway we were

able to enjoy mountain walks in broad

daylight all through the night!

In the winter though the Earth

moves around to the other side of its

orbit so the North Pole is facing away

from the sun. This means you get 24

hours of darkness each day in the

winter but that’s great if you’re looking

at the Northern Lights. This year is a

great year to see the Northern Lights

as the sun is at a ‘solar maximum’

meaning the Northern Lights will be

even brighter than usual.

Solar eclipses happen when the Moon

gets between the Sun and Earth,

blocking our view of the Sun (either

partially or fully).

When we saw the midnight eclipse in

Norway the Sun was low. My wife took

several photographs of the event, but

it’s not a very sharp image because of

the glare of the Sun. The bottom of the

Sun was behind a hill and the top of

the Sun was eclipsed by the Moon so

all you can see of the Sun is two bright

spots. You can just about make out the

‘dent’ caused by the Moon in the

photograph. The clouds in front of the

Moon were bright as they were lit from

behind by the light of the Sun.

As an added bonus on that holiday,

there was also an eclipse of the Moon.

This happens when Earth gets

between the Sun and Moon and the

shadow cast by our planet darkens the

Moon; its red colour during a lunar

eclipse happens because Earth’s

atmosphere scatters the blue light but

lets faint red light through.

Unfortunately that event was

completely clouded out!

A partial eclipse of

the midnight SunBy Simon Cran-McGreehin

Above: Earth’s axis is tilted at an angle

of 23½ degrees to the ecliptic plane (its

orbit around the Sun). This means that

at certain times of year there are places

which are always tilted towards the

Sun and it’s always daytime.

Graphic: Simon Cran-McGreehin.

Young Stargazers

Above: The eclipse in progress. The

Sun is mostly blocked by a hill with

the Moon just covering the top. The

picture on the right shows you what is

going on more clearly. Image: Simon

Cran-McGreehin.

Did you know? The beauty of the total solar eclipse

is due to a pure fluke of the cosmos.

It just so happens that the Sun is

about 400 times the size of the Moon,

but also 400 times further away. When

Earth, Moon and Sun are in precise

alignment the Moon perfectly overlaps the Sun and its

dark shadow just

touches a small part of

Earth’s surface.

Jargon buster

Northern LightsOtherwise known as the Aurora Borealis, the

Northern Lights are caused when strong winds

of energetic particles from the Sun are funneled

down onto the Earth’s north polar region by its

magnetic field. The particles hit atoms in the

atmosphere, making them glow. This also

happens over the southern magnetic pole,

causing the Southern Lights or Aurora Australis.



Dark matterHelp! I don’t understand ...

Dark matterIF we were completely honest

we’d end this article right here

by saying ‘No, nor does anyone

else!’ But at least we can talk about

why astronomers think there is

such a thing as dark matter, and

what it might be.

Curiously, there is a direct link

with the previous Help! article,

which was all about the

satellite orbits. That

article showed how

the time that a

satellite takes to

orbit Earth

(the orbital

period)

depends

on how

high

it is.

Actually,

there is

another factor as well and that is

the masses of the objects involved.

Compare Earth and Moon with

Jupiter and Io, for example. Io and

the Moon are roughly the same

diameter and mass, and orbit

roughly the same distance from

their parent planet. While the Moon

takes 27 days to go around Earth,

Io takes only 42 hours to go around

much more massive Jupiter.

The more massive the object (or,

to be picky, the greater the

combined masses of the two

objects) the quicker the orbital

period.

The same applies to stars orbiting

each other as well, which is why

astronomers can work out the

combined masses of double stars by

measuring

their orbital

periods, even

though the stars

may be hundreds

of light years away

from Earth. On a larger

scale still, it applies to the

movements of stars around a

galaxy and even galaxies in a

cluster of galaxies… and it is here

that the trouble starts.

The first signs were noticed as

long ago as the 1930s when

astronomer Fritz Zwicky realised

that galaxies in clusters were

moving much faster than they

ought to, as if they were moving

around a more massive cluster

than the visible galaxies alone

suggested. Their speed meant they

ought to fly off in all directions

rather than move really fast in an

orbit. Some unseen mass was

holding the clusters of galaxies

together.

Astronomers then found that the

same applied to stars, which all

seem to orbit their galaxies at

about the same speed, no matter

how far they are from the galaxy

centre. This meant there had to be

a lot more mass distributed

throughout the galaxy than was

estimated by looking at the number

of stars alone.

Astronomers started talking

about the mystery of the missing

mass—and there’s a lot of it! On

average, there is about six times

more gravitational attraction than

there is detectable matter.

What could it be?Now you might say ‘It’s obvious, it’s

black holes’. So astronomers have

been searching for these unseen

black holes by looking for their

effects on the light from distant

stars. If a black hole goes in front of

a distant star, its gravity will act as

a lens so there will be a sudden

apparent flare. Thousands of stars

have been monitored for such

flares, but the black holes just

aren’t there. In fact, the search also

rules out other possibilities such as

‘rogue planets’ plus other dark

objects like brown dwarfs.

So what about smaller things,

such as particles? Are there just

more, or heavier, particles than we

know about? Big Bang theory

successfully predicts how elements

form, but only comes up with the

same amount of matter that we

actually see. Astronomers conclude

that whatever makes up dark

matter, it isn’t the same stuff that

makes up stars and planets (and

us). That just leaves something

unknown—something with mass

but doesn’t interact with the rest of

the Universe.

A possibility is some kind of

`Weakly Interacting Massive

Particles,’ (WIMPs) that the likes of

CERN have not yet been able to

detect. Alternatively, maybe our

theories of gravity or quantum

mechanics (the way particles

interact) need to be modified. Right

now, no-one really knows how the

whole problem of dark matter will

be sorted out. But it’s the sort of

investigation that could lead us to

understand far more about the

structure of the Universe. And who

knows where that could lead?

by Robin Scagell

Spiral galaxies such

as M64, shown in this

Hubble image,

contain visible stars,

gas and dust. In

addition there is dark

matter, betrayed only

by its gravitational

pull on the visible

matter. Image: NASA.

Young Stargazers



What is ESTEC?ESTEC is ESA’s European Space

Research and Technology Centre,

based in the Netherlands. It is the

technical heart of ESA’s space

missions where most ESA missions

are born, developed and tested before

flying into space. The tests check that

the satellite won’t be damaged during

launch or when it’s in space. The tests

at ESTEC expose the satellite to

severe shaking and tremendous noise

to mimic launch, and to extreme

heating and cooling cycles for weeks

on end to represent the harsh

conditions in space. Testing goes on

for months until ESA is convinced

that the satellite is capable of

performing well for the whole of its

planned lifetime.

What’s your role?I’m the Space Science Editor, which

means that I write most of the news

stories that you see on the space

science section of ESA’s website

www.esa.int/science. These stories

cover the exciting results from all of

our space missions. There are roughly

20 space missions that I write news

articles about, some of which have

been in space for ten years or more,

while others are still being tested at

ESTEC. The missions cover the

Sun and planets in our own

Solar System, to stars and

galaxies across the

Universe.

Other editors at

ESA are in charge

of writing about

other aspects of

space exploration,

such as observing

our own planet,

astronaut missions

to the International

Space Station,

rocket launches, and

telecommunications.

I also write our ‘Space Science

image of the week’, which showcases

images from our missions—both

brand new, never-before-seen images

of the stars and planets and also

really stunning images from our

archives. One week it might be a new

Cassini image of Saturn and the next

it might be ExoMars being tested in

the ESTEC test centre. Check the

space science page each Monday for a

new image.

What have been

the most exciting

stories you’ve

worked on?When I first started at ESA

more than a year ago I was

lucky to be invited to go to

Svalbard with the Venus

Express science team to

report on the transit of

Venus—to watch Venus

pass in front of the

Sun—an event that

won’t happen again this

century. Svalbard is an

island located about

halfway between

mainland Norway and

the North Pole, and

when we visited

in June, it was

daylight all

day—the Sun

never set! It was

one of the few

places in the

world where

you could

watch the

entire transit

from beginning

to end, and we

only had a few

interruptions from

clouds.

One of our more recent stories was

the grand unveiling of the most

precise image of the Cosmic

Microwave Background (CMB)—the

relic glow of the big bang that created

our Universe nearly 14 billion years

ago. ESA’s Planck space telescope has

been making sensitive observations of

this radiation since

it launched in

2009.

After years of painstaking detective

work sifting through all the data,

Planck scientists finally showed the

new ‘baby photo’ of the Universe in

March 2013. There was a lot of media

coverage after ESA released the

image, and the story made it to the

front page of the Financial Times, the

New York Times and many other

newspapers across the world. It was a

very proud and exciting moment for

everyone involved in the project.

What’s it like to work at the

European Space Agency?Former SPA Chief Stargazer Emily Baldwin drops by to tell us all about

working as space science editor at ESA’s ESTEC in the Netherlands, and the

exciting space missions that we should all be watching

Emily

views the

transit of

Venus using

‘eclipse

glasses’.

Despite being

‘night time’

it was sunny,

but still very

cold!

Planck’s

CMB

image will

help scientists

learn more about

the development of the

Universe. Image: ESA.

Young Stargazers



In June 2013 ESA’s Mars Express

mission celebrated ten years since

launch. The mission has been

observing all aspects of Mars’

environment, from below the surface

to its atmosphere and beyond to its

two moons Phobos and Deimos.

Perhaps it is best known for the

stunning 3D images it takes of the

Martian surface, highlighting

different environments from volcanoes

to ice caps to valleys that may have

been carved by water. To mark the

mission’s 10th birthday, scientists

presented a new global mineral atlas.

These include minerals that formed

only in the presence of water and

minerals formed during volcanic

eruptions, so plotting where and how

old they are helps trace the planet’s

history. The maps will also be used to

help choose the landing sites of future

missions, such as ESA’s ExoMars

missions that launch in 2016 and

2018.

If you enjoy looking at Mars then

take a look at ESA’s website each

month for a new set of images from

Mars Express. It’s always exciting for

me to see the new images and use my

planetary science degree to

understand what the pictures are

telling us about the planet, and then

share it with all of you.

Great things to comeThere’s always something exciting

happening at ESA but there are two

big missions coming up in the next

year that are particularly important

for space science. One is the Gaia

mission. It is equipped with a 1,000

megapixel (that’s a billion pixel

camera; for comparison my mobile

phone has a 5 megapixel camera) and

it will study a billion stars. Its goal is

to make the largest, most precise 3D

map of our Galaxy by precisely

charting the positions, distances,

movements, and changes in

brightness of the stars. It is also

expected to discover new exoplanets,

asteroids and failed stars called

brown dwarfs.

Meanwhile the Rosetta mission

finally reaches its destination in 2014.

The spacecraft launched in 2004 and

has passed three times around Earth,

once around Mars and has flown by

and imaged two asteroids, before

going into deep space hibernation in

July 2011. In January 2014 Rosetta

will get a wake-up call as it draws

closer to its final destination: Comet

67P/ Churyumov-Gerasimenko (I’ll

need to practice how to say—and

spell—the comet’s name!).

The mission will be the first to

follow a comet as it makes its journey

around the Sun, and watch as its icy

surface is warmed up by the Sun. It

will also be the first mission to land a

probe onto a comet’s surface. There it

will study the comet’s surface, helping

scientists to learn more about these

‘dirty snowballs’ that could have

helped give Earth its water billions of

years ago.

Life in the

NetherlandsIt is fantastic to live in a new country.

Every day I interact with colleagues

from all over the world, so I learn a

lot about different cultures and

languages. Although everyone speaks

English at work, I’m trying to learn

Dutch. My partner also moved to the

Netherlands with me and we have

enjoyed exploring other parts of

Europe that are now a lot closer and

easier to get to than if we were in

England. But it’s still easy to visit our

friends and family in England, and

we were pleased to see lots of our

astronomy friends—including our

SPA friends—at AstroFest last year.

Where is ESA?ESA has sites all over Europe:

1. ESA’s Headquarters are in Paris, France.

2. ESTEC, the European Space Research and Technology Centre, is ESA’s

largest site, based in the Netherlands. Here satellites are tested before

they go into space.

3. ESOC, the European Space Operations Centre, is in Darmstadt,

Germany. ESA spacecraft are controlled from ESOC during their missions.

4. ESRIN, the Centre for Earth Observation, is in Frascati, Italy

5. ESAC, the European Space Astronomy Centre, is ESA’s centre

dedicated to space science and astronomy, and is based near Madrid,

Spain.

6. EAC, the European Astronaut Centre is in Cologne, Germany, and

trains Europe’s astronauts, including the UK’s Timothy Peake.

7. ESCAT, the European Centre for Space Applications and Telecoms,

recently opened in Harwell in the UK.

7 2

6

1 3

4

5

Find out moreESA Space Science: www.esa.int/Our_Activities/Space_Science

Space Science Image of the Week:

www.esa.int/Our_Activities/Space_Science/Image_of_the_week_archive

Take a virtual tour of ESTEC’s test centre:

esamultimedia.esa.int/multimedia/ESTEC/virtualtour/

Download space science mission posters:

www.esa.int/Our_Activities/Space_Science/Wallpapers

ESA homepage: www.esa.int

Emily’s ESA

portrait.

Image:

ESA.

Young Stargazers



Astronomy Diary

2014 (Kickstarter

project)Discover the mysteries of the Universe

By Kate and Julian

www.astronomydiary.co.uk

Softback, 66 pp / £10 (to pledgers)

This is a first for the Reviews section of

Popular Astronomy—a review of a book

yet to be published, and may never be

published unless it receives a certain

amount of funding from potential

buyers.

This new astronomy book was

recently launched on crowdfunding

website Kickstarter. Aimed at

promoting naked eye observing, the

project, if successful, will fund the

publication of a novel pocket-sized

astronomical guide—Astronomy Diary

2014.

Described as a ‘What’s On’ guide for

the night sky, Astronomy Diary 2014

will give weekly recommendations for

observations and must-see celestial

events.

The authors are two Londoners, Kate

and Julian (whose surnames I couldn’t

find) who had trouble

dedicating time to

their passion for

stargazing.

What

began as

their

personal

plan to list and

view the must-

see celestial events

of 2014 could now end

up in the hands of

astronomers across the

country, if the couple’s

Kickstarter project gets funded.

Astronomy Diary 2014 aims to spark a

lasting interest in astronomy in both

adult and young newcomers to the

hobby, but could also act as a handy

aide to more experienced observers. It

features weekly recommendations for

the most popular objects visible to the

naked eye or with binoculars. It

includes transient events such as

meteor showers, conjunctions and

eclipses, the positions of planets and

phases of the Moon along with

established sights such as

constellations, famous star clusters,

galaxies, nebulae and double stars. Key

historical dates related to astronomy

and space exploration are also included.

Being a diary, space is left for the

reader to record their own notes and

observations of celestial events.

It all looks a very worthwhile

project and from the

material posted online

(see websites below) it

looks very nicely done and

well-presented. Kate and

Julian have until 14 November to

fund their project and make their

idea into reality.

For more information about this

Kickstarter project, see:

www.kickstarter.com/projects/15178340

76/astronomy-diary

Official website:

www.astronomydiary.co.uk/

Contacts:

[email protected]

Peter Grego

Please note that I have no vested interest

in this book, nor am I a pledger, but I

will be keeping an eye on its progress.

We will feature a review of the book

itself in the January-February issue of

Popular Astronomy if it comes to

fruition.

The Cambridge

Photographic

Moon AtlasBy Alan Chu, Wolfgang

Paech and Mario Weigand

(translated by Storm Dunlop)

Cambridge University Press

ISBN: 978-1107019737

Hardback, 192 pp / £35

As a keen lunar observer, I’m

always excited when a new book

about the Moon is published,

especially when that new book is

a lunar atlas.

Printed in large format

(measuring 1.8 × 25 × 33.8 cm)

this latest attempt to illustrate

the wonders of our natural

satellite’s visible hemisphere is

nothing but spectacular.

Photographic coverage of the

Moon’s near-side is achieved in

the illustration of 68 regions with

388 different images. These

regions are loosely delineated and

centred around certain major features,

with attention drawn to a variety of

interesting formations. Because of this,

the atlas isn’t as as easy to search

through as, say, Rükl’s neatly-defined

Atlas of the Moon; nor does it show all

the sections under a variety of

illuminations, like Hatfield’s

Photographic Lunar Atlas. But this isn’t

a problem, as key annotated images

showing the areas depicted are given at

the front and back of the book.

All the images were secured by the

authors, each of whom is a skilled lunar

CCD imager. Chu more than

successfully images the Moon from his

balcony overlooking an unfeasibly

vertically urban Hong Kong using a

10-inch Newtonian, while both Paech

and Weigand do their astronomy from

Germany, using a 6-inch refractor/14-

inch SCT and 11-/14-inch SCT

respectively.

Opinions on a selectionof astronomy books and

productsReviews



Reviews

There’s more text to this atlas than in

the Rükl or Hatfield atlases. The

Moon—an Introduction makes up first

26 pages. Here the authors attempt an

summary of the Moon as a world, a

potted history of lunar geological

processes (with some reference to older

theories), a discussion of the Moon in

space and information and advice on

lunar observing with particular

emphasis on CCD imaging. All of this is

very well-illustrated with images by the

authors along with NASA photographs.

The sheer quality of the images, many

of which are so good as to be presented

very large without a trace of pixellation,

really makes this book stand out from

other Earth-based photographic Moon

atlases.

Although many of the images are

overlain with labeling, the style in

which this has been done makes the

text, dots and lines completely

unobtrusive—that’s a great

accomplishment and I take my hat off

to the graphics people at CUP.

The meat of this atlas is the 68 near-

side sections (plus one grudging

single-page section on the far-side at

the end!), which take up 154 pages.

Unfortunately there are no page

numbers in the atlas part, even

though their inclusion would have

been very handy and in my opinion

wouldn’t have detracted from the

design. Arranged in an order that

generally follows the progress of the

lunar day, they are all accompanied by

notes explaining various features in

the images, some obvious and others

les grand but of high interest.

This atlas’ meat is exceptionally

tasty, and one feels almost guilty for

indulging in it, so beautiful are the

images. It’s wonderful to view so many

familiar features—craters, mountains,

domes, ridges, faults and valleys—in

such sumptuous detail. It’s the

nearest thing you can get to actually

seeing them for real under good

conditions (and to do that you need a

telescope). I would say that the

minimum level of lunar detail in the

lowest-resolution image in the atlas

equates to that visible with the acute

eye at the high-magnification ocular of

an 8-inch telescope, and the best ones

show detail that is unattainable

visually with an amateur instrument.

Most of the images are in black and

white, or seem to be tinted very,

slightly, almost imperceptibly brown

(to my eyes), while some are in colour

(a realistic colour without saturation,

matching the eyepiece view). The

finest of the colour images is

undoubtedly that of the Aristarchus

region (section 58), showing a Wood’s

Spot of glorious raw Sienna and a

blue-grey region intruding into it from

Aristarchus.

The most obvious error is the

transposition of the images featured in

the lower part of sections of 41 (South

Pole) and 54 (Sinus Iridum); this

unfortunately sees a wrinkle ridge in

Mare Imbrium identified as the South

Pole and the South Pole identified as

Sinus Iridum.

The geological descriptions are very

good, but I have a few bones of

contention. For example, on p15 it is

stated that the Iridum basin was

formed by impact before the Imbrium

basin; the superposition of the former

by the latter makes this very unlikely. I

was not convinced by explanations of

several other features in the atlas. For

example, craters with smooth-looking

flat floors aren’t all lava-flooded; many

of them are more likely covered with

impact melt (as described in section 1).

This goes for some other smaller craters

whose smooth floors are likely wrongly

ascribed to lava. In the case of the

ancient crater Newcomb C (section 3)

the floor is more likely smooth because

of erosion and overlying ejecta deposits.

It is however true that many larger

craters do have lava flooded floors, as

they ruptured the crust sufficiently to

allow mantle material to rise to the

surface. I’m also reluctant to accept that

lunar geologists believe that the inner

rings of small double-walled craters like

Hesiodus A (p21, section 46) are

attributable to the intrusion of highly

viscous magma in an annular zone.

With respect, I think that this is fair

criticism, because although I’m not a

qualified geologist (let alone planetary

geologist), neither are the authors.

Historically, lunar geology has been

coloured by both amateur and

professional speculation, and I dare say

my own work The Moon and How to

Observe It (which the authors kindly

mention in Further Reading and

References) can be criticised in like

manner!

I congratulate the authors on

producing this atlas. It is a beautiful

book that now takes a proud place on

my bookshelf, and I will probably

consult it often. I thoroughly

recommend it to every astronomer

(amateur or profesional) with an

interest in the Solar System.

Peter Grego

Revised and Updated Edition

By Ben Bussey and Paul Spudis

Cambridge University Press

ISBN: 978-0521141017

Softback, 317 pp / £35

In 1994 the NASA/DoD Clementine

mission gave us our first global

view of the Moon as it imaged the

surface in various wavelengths

from lunar polar orbit. This atlas

presents us with the UV-visual

results of that overview, tying it in

with the more recent Lunar

Reconnaissance Orbiter (LRO). Perhaps

it would have been better titled The

Clementine/LRO Visual Lunar Atlas.

The first section describes the Moon’s

geological history, plus a short history

of lunar science and exploration. The

atlas itself consists of 144 black and

white maps

compiled from

Clementine UV-

VIS imagery

covering the

whole lunar

surface, each

showing an

overhead view

of an individual

area. These are

presented in

two-page

spreads, along with a corresponding

map based on more LRO data/imagery

(the latter being a new feature of this

updated edition). First published in

hardback in 2004, this is a most

welcome revision and an essential for

any Moon fan. Peter Grego

The Clementine Atlas of the Moon



LettersThe Seeliger

Effect—on Earth as

it is on Saturn?I was intrigued to hear of the ‘Seeliger

Effect’ in Alan Clitherow’s Planetary

Section report (PA Sep-Oct 2013). The

apparent brightening of Saturn’s rings

around opposition sounds very similar

to an oft-reported terrestrial effect.

Many pilots, and the occasional

passenger, have noticed the effect when

flying over a field of grass or a prairie

full of grain. Looking directly away

from the Sun, the shadow of the plane

appears surrounded by a bright circle in

the corn a degree or two across.

There are two effects at play. The first

is the obvious effect that if one looks at

any illuminated object then you will see

more reflected light from straight on

than if looking from the side. This effect

is very small; for a one degree offset,

the loss of light is only 0.015% and at

six degrees the loss is still barely half a

percent. Hardly enough to be noticed by

the human eye. Think of the secondary

mirror in a reflecting telescope. In a

Cassegrain, a circular mirror turns the

light 180 degrees. In a Newtonian,

where the light is turned 90 degrees, an

elliptical mirror is used because a

circular one would lose 30% of the light.

The second, and more significant,

effect is believed to be shadowing.

When viewed straight on, all the

reflected light returns on the same path

on which it went in; an un-obstructed

path to and from each and every blade

of grass. When viewed from even a very

small offset, some of the light reflected

from the more remote grasses will be

intercepted by grasses nearer to the

observer. Hence the observer is looking

at a mixture of illuminated surfaces

and surfaces hidden in shadow. The

Seeliger Effect would seem to be the

same shadowing effect among the

particles making up the rings of Saturn.

Saturn is 9.25 times the mean

distance of the Earth and its orbit is

inclined at 2.5 degrees with respect to

Earth’s orbit. At opposition therefore,

calculations with the simple geometry

of sines and cosines show that the

sunlight will be diverted by anything

from 0 degrees (at either of the nodes

when Saturn is in the plane of Earth’s

orbit) to 0.29 degrees (when opposition

occurs with Saturn at maximum

declination above or below the ecliptic).

Even at quadrature, the reflected light

will be diverted by no more than about

6.0 degrees. Could a plot of intensity of

reflected light against diversion angle

tell us anything about the particle

density in Saturn’s rings?

A third mechanism, that of the corner

reflector, might be at play in the ring

particles; though not in a field of corn. A

corner reflector can be made from three

mutually perpendicular mirrors; the

inside corner of an empty box. Any

beam of light that reflects of all three

mirrors in sequence will be returned to

its source. This is the principle behind

the ‘eight-corner radar reflector’ that is

often flown from the masthead on small

fishing boats. A corner reflector can also

be made from a transparent solid of

sufficiently high refractive index; the

outside corner of a full box. Any beam of

light that gets into

the solid and then

undergoes total

internal reflection at

all three

solid/vacuum

interfaces in

sequence will also be

returned to its

source. This is the

principle behind the

red-plastic reflector

on a car or the clear-

glass ‘cat’s eye’ in

the road. Could some

of the material

forming Saturn’s

rings be a

transparent mineral

that forms crystals

with cubic-orientated

plane surfaces?

Brian M. Russell

Alan Clitherow replies:

The generally accepted explanation for

the Seeliger Effect is the ‘shadowing’ you

refer to. In simple terms the reflective

particles in the rings scatter light in all

directions; however, they also cast

shadows that are visible when they fall

on particles behind them. When viewed

from anywhere other than directly in

line with the light source these shadows

darken the overall visible picture. When

viewed close to opposition these shadows

are hidden behind the particles casting

them so the overall darkening effect of

the shadows disappears.

A similar effect can be seen when

comparing the brightness of the full

Moon with that of a first or last quarter

Moon. In general you would expect the

full Moon to be twice as bright as a

quarter Moon since the illuminated area

is twice as large. In fact it shines

noticeably more brightly as there are no

dark shadows cast by relief features to

be seen anywhere on the disc, shadows

that effectively cut the visible reflective

area of a quarter Moon.

Thinking about this from a slightly

different point of view, if the rings of

Saturn are made of randomly orientated

reflective particles then from any given

viewing angle one will see a number of

particles that just happen to be reflecting

sunlight towards us, and this light will

have been reduced by scattering off the

randomly floating particles that

intervene with that reflected light-path.

When the Sun is directly behind us and

the rings are directly in front of us any

aligned reflected path has the shortest

distance to travel through the

intervening particles resulting in the

minimum amount of light scattering;

more reflected light reaches us and the

rings appear brighter. This effect will be

smallest when the particles are equally

reflective in all directions and largest

when the particles have only a small

highly reflective face as found with

complex crystalline structures. This

would be particularly true of any

particles having 90-degree edge

reflectors within crystalline structures

(or allowing total internal reflection

within a refractive molecule) but I do not

specifically know of any such within

Saturn’s rings.

A variation on this approach involves a

‘coherent backscatter effect’ in which the

reflected light is enhanced at narrow

angles if the size of the scatterers in the

reflected light path is comparable to the

wavelength of incoming light and the

distance between scattering particles is

greater than a wavelength; the result, as

Your comments, views,opinions, news, stories,suggestions and poems

A surge in brightness appears on Saturn’s A ring

directly opposite the Sun from the Cassini

spacecraft. This ‘opposition surge’ moves across the

rings as the spacecraft watches. This view looks

toward the rings’ sunlit side from about 9°

below the ringplane. Image: NASA.



Letters

I understand it, is that the reflected light

bouncing back towards its original source

is coherent with the incident light and

there is no scattering or destructive

interference. I will confess to being at the

limits of my knowledge here and would

welcome an expert stepping in.

Variations in the orbital inclinations of

both Saturn and Earth will cause

variations in the overall amount of

brightening as you suggest, simply

because our viewing angle varies closer

to or further away from the direct line

between Sun and Saturn. However the

biggest factor must be the apparent

change in inclination of the rings as seen

from the Earth since the total reflective

area dramatically increases as the ring

angle increases; giving either brightening

effect more area to have an effect on.

As for the ‘circle of brightness’ around

an aircraft shadow when seen from that

aircraft: this is known as a ‘glory’ and is

something I have seen and photographed

a number of times. It can be understood

in the same terms as the shadowing

effect already described when the

illumination falls on a solid object. When

it falls on dispersed particles, such as

water vapour in a cloud, its cause is still

disputed but seems to involve either two

internal reflections interfering with each

other within a rain-droplet or bizarre

quantum tunneling effects whereby a

photon-wave passing close by, but

missing, such a droplet still imparts

some energy to it. In either case it

causes the reflected light to be changed

in frequency (rainbow effects) and

dispersed rather than concentrated. For

this reason I doubt it has much

application to the Seeliger Effect

arising from dispersed particles within

Saturn’s rings

Alan Clitherow

A close-up of the visor of Buzz Aldrin’s

helmet, showing the opposition effect

brightening the area around Aldrin’s

shadow. Image: NASA.

Nova Del 2013I sent this observation

into the SPA’s

Variable Star

Section, but I

thought you

might be

interested in

seeing it too.

It’s been a

while since I

have had

chance to do

much

observing, but

news of Nova

Delphini 2013

piqued my interest,

and I have been

fortunate to be able to

make a couple of observations. The

first was in the early hours of 18

August at 03h UT. At that point the

nova had faded slightly from its

original peak. Unfortunately, I’m not

very experienced at estimating star

magnitudes, but my very rough

estimate put it close to mag. +5.5. I

managed to make this supporting

sketch, from my second observation.

This was drawn

on 22 August at

21:41 UT, when the

nova appeared slightly

fainter still.

I think this is the first time I

have ever observed a nova, and it was

fascinating to imagine the process

that has taken place to result in this

incredible brightening.

I shall keep watching, as and when

I get the opportunity, and follow the

progress of this event.

Jeff Stevens

Stoke-on-Trent

Jeff’s observational drawing of Nova

Delphini 2013, made using

8×56 binoculars. North

is at top. The nova is

at the intersection

of the two lines,

with an

estimated

magnitude of

+5.7. The

brightest star

to the far left

is 29

Vulpeculae,

at mag. +4.8.

New brush

sweeps

cleanerMy new

Canon 600D

(18.7 Mp)

has a lot

more to

offer than

my 1100D

(12.2 Mp). It

can shoot 30

frames straight

off of a moving

subject and on

image stabilizer

automatically in several

configurations. Fantastic

resolution. You can open the display

screen and turn it round to any

position, or simply slot it into the back

and use it like one without that type of

hinged display.

I attach an image I took at 18:30 on

15 October over my garage, using a

Canon 300 mm lens lens and not a

telescope. The waxing gibbous Moon

was very bright and the starry sky was

brilliant. I stacked seven images in a

software program I have to take away

the blurring of the sky

background. No other

processing was

needed. I’m going

to try and get

all 28 phases

of the Moon

as a quick

project over

the months

ahead. It

only takes a

few minutes

each evening

to do some

snapshots.

John Fletcher

Mount Tuffley

Observatory,

Gloucestershire

Express yourself!Popular Astronomy welcomes

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some time for a response.



The Moon

Recent observations. The short nights

of the late spring and early summer

generally lead to a lull in meteor observing

and a reduction in fireball reports. Night

time meteor rates do pick up in late July

however and reports of Aquarid /

Capricornid activity and of early Perseid

activity had been received from Graham

Winstanley and Alex Pratt by the time the

column was written in early August. Alex

noted in particular that he had captured

images of six Alpha Capricornids. Given

its low ZHR, this shower might not appear

very promising. However the meteors that

it does produce can be very memorable—

they are typically slow moving and often

have distinctive colours and long paths.

Perseids vs Geminids. Which meteor

shower is the best in terms of fireballs? An

article published by NASA in late July

made the claim that the Perseids are the

‘fireball champions’. This surprised many

experienced meteor observers as their own

experience was that Geminid meteor

watches produce a higher percentage of

fireballs. However, closer inspection of the

article revealed that it actually referred to

the total number of fireballs produced by

each shower. Although the Perseids

produced a significantly higher number of

fireballs than the Geminids did, this was

almost certainly merely a consequence of

the Perseids having a longer activity

period and therefore having more nights

to build up their total. The article can be

found at science.nasa.gov/science-

news/science-at-nasa/2013/26jul_perseids

Bright flashes. Flashing objects are

sometimes seen in the night sky. In some

cases the objects show repeated flashes as

they cross the sky. Aircraft are the most

common example. Some satellites also

produce regular flashes as they ‘tumble’

along their orbit and their solar panels are

periodically lit up by sunlight. Single very

bright flares can be seen from Iridium

communications satellites, but these also

show some motion during the flare. More

unusual are stationary flashes at a point

in the sky. Some of these will be head-on

meteors or strongly twinkling faint stars.

Others could merely be flashes in your

eyes (or more precisely random firings of

neurons in the optic nerve). There are

cases however that do not fit these

explanations in that they are seen at the

same point in the skies by observers

several miles apart.

SPA contributor Peter Meadows

highlighted an example in a recent issue

of The Astronomer magazine. His image

and another taken several miles away

both recorded the object. Had the flash

been from a meteor or from an aircraft

there would have been a small difference

in the object’s position against the star

background between the two images.

Since there was not, the object must

therefore be more distant. Peter suggested

that the most likely explanation was a

specular reflection (glint) from a satellite.

Tony Markham

Section reports

Since our report in the Sep-Oct issue of PA,

observational lunar drawings have been

made by Dale Holt and me. In addition, a

wide selection of lunar CCD images has

been submitted by Mike Brown, David

Finnigan and David Scanlan. If I’ve missed

anyone out, please let me know, as I receive

lots of lunar material from non-SPA

sources.

Our subject is the crater Hippalus on the

southeastern shore of Mare Humorum. My

observational drawing of sunrise over

Hippalus (made on 20 April) was featured

in the Lunar Section report of the Jul-Aug

issue of PA; this latest observation (shown

at left), was made on 14 October and shows

the feature at a slightly more advanced

illumination.

From its appearance, Hippalus is

evidently very ancient and has had

a chequered history. After its

impact formation it was subjected

to further impacts, producing its

oddly scalloped shape; its western

wall and floor was then flooded by

lavas from Mare Humorum. Once

this had solidified, crustal tension

around the mare edge produced the

arcuate rilles (known as the Rimae

Hippalus) that cut through

Hippalus’ floor and walls. There is

lots of fascinating detail in the area,

such as mountains and low ridges.

You can view a similar scene of

sunrise over Hippalus on 14

November and 12/13 December.

Peter Grego

View a scene of

crater catastrophe

Top: Sequential observation of Hippalus

made on 14 October at 20:45 to 22:20 UT

by Peter Grego (12-inch Newtonian).

Right: David Finnigan’s image of Mare

Humorum and Hippalus (with enlarged

detail above) taken two days later (12-

inch SCT, ZWO ASI 120MM CCD).

Odd flash probably

no point meteor

Observations, news and notes from the

SPA Observing Sections (all times UT)

Meteors



Occultations

It has been a quiet couple of months for

the section with no reports coming. That

being said, information regarding

occultations has been given out to those

requesting it.

For this coming period, November to

December, we have seven reappearances

and three disappearances (not including

the disappearance of Lambda Geminorum

at the Moon’s bright limb)—for a full

listing of occultation events see Sky Diary

on p44.

On 22 November, the magnitude +3.6

star Lambda Geminorum is occulted

(graphic shown at right). I have included

information for the disappearance at the

bright limb, which occurs less than an

hour before the reappearance at the dark

limb of the Moon.

The early morning of 24 November sees

the magnitude +5.4 star 60 Cancri

occulted by the 66% illuminated waning

gibbous Moon, as seen from London. The

north of the country will see an appulse.

The graze line for this event (shown on

the map here), running west to east, is as

follows: west coast of Eire, just north of

Belmullet, and across country to the east

coast of Ireland north of Ardglass. The

line crosses the Isle of Man to the west

coast of mainland UK just to the north of

Barrow-in-Furness, it travels across

northern England, north of Harrogate

and York, through Old Malton (Malton,

north Yorkshire) and then out to the east

coast at Flamborough Head. Anyone

south of this line will see a reappearance

of the star. If you require a more detailed

map of this grazing event, please do get in

touch and I can provide the Google Earth

file for you.

19 November’s two occultations will be

difficult observations due to the waning

gibbous Moon being 98% illuminated. As

mentioned in information on previous

events of this nature, try to keep as much

of the Moon out of the eyepiece as possible

and familiarise yourself with the region of

the Moon where the star is to reappear.

For those new to observing occultations

and not wishing to be up in the early

hours of the morning, the disappearance

of magnitude +4.3 Epsilon Piscium

behind the dark limb of the waxing

gibbous Moon on 11 December, should be

a good one to attempt (see graphic below).

Because the star disappears behind the

dark lunar limb, you will be able to

observe the star right up until it

disappears. It’s watching this type of

event that shows you that the Moon is

moving against the background stars, as

well as the Earth rotating causing them

to rise and set.

Another feature of occultations to watch

for is when a star doesn’t immediately

appear or disappear, such as in cases

where the star is a known double star.

The brighter star may disappear, leaving

the usually unobservable fainter

companion visible for a brief while.

Alternatively, the fainter star may

reappear from behind the dark lunar limb

before the brighter one. A number of

double stars have been discovered this

way.

Any observations of occultation events

are welcome, timed or not. If you require

further information please get in touch.

Mell Jeffery

Northern graze

The graze path of

60 Cancri on 24 November.

Image: Google Earth.

Section reports

Lambda Geminorum is

occulted on 22 November. Its

disappearance at the Moon’s

bright limb will prove difficult to

observe, but its reappearance at the

dark limb around an hour later will

be much easier to see.

The disappearance of

Epsilon Piscium on the

evening of 11 December

provides a good

introduction to

observing

occultations.



Report for June and July. The section

recorded a relatively low number of

observations during the period; this is

understandable with Saturn sinking into

the western sky and no other well-placed

planets to observe. However the period was

successful for two reasons. Firstly, the

proportion of visual observations increased,

revealing something interesting about

Saturn’s largest moon Titan. Secondly,

some new cameras and interesting

processing and imaging techniques have

produced better images of Saturn than

expected given the conditions.

Starting with visual observations, both

Alan Heath and Matthew Barrett sent

detailed reports despite what Alan

described as his ‘worst ever apparition’ of

Saturn due to weather. These reports give

estimations of the visual intensity of the

major visible bands, zones and rings, as

well as notes on the position and colour of

major moons, Titan of particular note in

this case. The intensity estimations were in

close agreement between the two

observers; there were obviously some

variations, but Matthew’s observation of 5

June and Alan’s of the 6th were almost

identical. Visual estimations are useful

when looking for variations over time and

for comparison with images. Both methods

of observation are very useful and I’m glad

visual reports are increasing.

One interesting point was Alan’s

estimation of the visual colour of Titan. On

10 June he recorded it as a creamy-yellow

colour whereas on the 6th it had appeared

a deep red. He acknowledges that the low

altitude of observation will play tricks with

observed colour, but noting no significant

changes in seeing conditions between the

two observations he was struck by the

colour change; certainly there was no big

change in elevation in four days. In order

to see if there was any obvious correlation

between colour and orbital position he then

plotted dated colour estimates taken from

both this year and 2012 against Titan’s

orbit. From this he suggests that Titan

seems least red when approaching its

farthest point to the west of Saturn. Alan’s

own records of estimations of Titan’s colour

date back to 1958 and he intends to look

closer at these to further investigate this

subject. Observations by NASA’s Cassini

probe indicate that there is a sound basis

for Alan’s observation. Any other reports or

observations on this topic are welcome.

Saturn remained the only object imaged

by section members—indeed it was pretty

much the only game in town during the

period. Section members contributing were

Mike Brown, David Finnigan, Martin

Lewis, Steve Norrie, Paul Crossland and

myself. Early June was well-reported with

multiple observations during a clear period

extending to the 10th.

With Saturn less than 27° high and with

strong winds in our own atmosphere

causing unsteady seeing, Mike Brown

compared the planet’s visibility through a

range of filters. Red and near infrared (IR)

light cuts through turbulence better than

green and blue light, especially blue which

gets scattered, dimming it considerably.

Mike’s images from 3 June compared

results through red, green and blue filters

on a monochrome camera with extra

images taken through a Baader IR-pass

filter (685 Nm +) and a Hoya IR pass filter

(830 Nm +). The biggest limit to what can

be resolved is the steadiness of our own

atmosphere. In theory resolution increases

as the wavelength of observed light is

reduced, which should make blue or even

ultraviolet the filters of choice for planetary

observers seeking maximum detail. But

these are the parts of the spectrum most

scattered by the atmosphere. So, IR filters

are a compromise; they can’t provide the

ultimate detail visible at shorter

wavelengths on a steady night, but with

poor seeing they can provide the maximum

amount of detail that conditions allow. In

Mike’s case, a combined image using red

light and two frequencies of IR allows

almost all the Cassini Division to be

resolved along with a hint of the Encke

Gap and all major banding in the planet’s

cloud structure. An excellent example of

how to make the most of conditions.

Dave Finnigan, now imaging with a 12-

inch SCT and a DBK21 colour camera, also

made some comparisons. To get the best

from his captured video files he ran them

through both v5 and v6 of Registax and

through v2 of AutoStakert. These are all

excellent bits of freeware and Dave wanted

to see which produced the best result from

a single AVI video of Saturn taken in poor

seeing. In each case the software selected

the best 1,000 frames from the file, then

combined and stacked them into a single

image. The results were close; all three

images showed some evidence of

misaligned frames but the best

combination, by a slight margin, came from

AS2 while R6 just beat R5. Choosing the

number of images to extract and stack

from a video file is a tricky. Some think

that more is always better, while others

(like myself) think that only the best 10%

or so should go into the stack to produce a

final image. More often produces a

smoother, more natural-looking result;

fewer can give a more detailed if somewhat

grainy image. The best advice is to stack

more images if seeing is good, fewer if it is

bad, and play around with the number to

see which gives the most pleasing result. I

agree with Dave that AS2 is currently the

easiest stacking-software to use.

More comparisons of equipment and

technique came from Martin Lewis, who

normally images planets using a DMK21

monochrome camera and colour filters. He

recently began using a one-shot-colour

camera to see if good results can be

obtained with less time spent on image

processing. At the moment the very best

amateur planetary images are rather

painstaking to produce. First, a

monochrome camera is used to take videos

through red, green and blue filters. A

number of these are taken alternatively

over an extended period and each file is

individually processed to produce an

image. These multiple images are then fed

into WinJUPOS, freeware which maps

each image onto a spheroid the same shape

as the target planet, precisely layering and

positioning each image according to the

exact time it was taken. This allows the

extraction of a final colour image that

avoids blurring caused by the planet’s

rotation during the extended capture.

Martin tried layering an image of Saturn

taken with one camera, a monochrome

DMK21, over a colour image taken with an

ASI-120MC, as a luminance layer. This

required taking just two images, which can

be done quickly enough to avoid blurring

due to planetary rotation. The result is

sometimes comparable to WinJUPOS

images and Martin reports that the time

savings are huge. He also uses an

Atmospheric Dispersion Corrector (ADC,

referred to in previous reports) when

observing low targets. He compared two

colour video runs, one with and one

without the ADC. The results are shown

on p47; the device clearly gets the best

from low altitude targets, especially since it

can be used visually as well as

photographically.

Finally, Marc Delcroix

(non-member) imaged

Uranus on 1 July

through a big telescope

from the French

Pyrenees (shown here)

using a monochrome camera and Baader

infrared pass filter (685 Nm +). Subtle

banding on the planet was captured. I

leave this as a challenge for a member to

better in the next reporting period?

Alan Clitherow

Saturn, the only game in town

Section reports

Saturn, from SPA report form for

2 June, with intensity estimates.

Planets

Observer: Matthew Barrett.



The Deep Sky Section has received

observations from three members in

the past couple of months: Dale

Holt, Dave Finnigan and Eddie

Carpenter.

Dale sent in five

observations using his Watec

120N+ astro video camera

combined with either his

20-inch Newtonian or 6-

inch refractor. Starting in

Sagittarius, Dale observed

M21, a small open star

cluster. With his refractor

it showed pretty much the

central region of the

cluster, a lovely circular

ring of stars. Also in

Sagittarius, Dale observed

NGC 6642, a small globular

cluster located near M22. This

object is very distant, and being in

the plane of the Milky Way it is

obscured by lots of interstellar

dust. Dale’s sketch shows a

very compact ball of stars,

very granular in appearance

with a few brighter

superimposed stars.

Moving into Aquila,

which again is in the plane

of the Milky Way, Dale

observed the faint galaxy

NGC 6814. The position of

this galaxy means that it is

obscured by lots of interstellar

dust, and through the eyepiece it

appears quite diffuse. Dale

managed to record some slight internal

detail, a faint central core and a mag.

+13.5 star within the galaxy itself.

An interesting planetary nebula can be

found in Cygnus. NGC 7026 also has the

interesting nickname of the ‘Cheeseburger

Nebula’ as it resembles a burger seen

from the side. Dale mentions that his

refractor actually gave a sharper view of

the nebula and split the two sides more

clearly, showing the central star.

Our next contributor, Dave Finnigan,

sent in eight observations using his 12-

inch LX 200 ACF at f/6.3 and a DSI II pro

camera. His first observation was of the

large bright globular cluster M2, which

was well resolved. Another globular, M14,

pretty much filled the frame; this object

had masses of stars and actually looked

three dimensional.

Moving down to Sagittarius Dave

observed M22. His very nice observation

showed a large globular, the central

region consisting of fainter stars with

several brighter stars scattered across its

face. Dave also observed globular cluster

NGC 6712, located in Scutum. This is a

very dense cluster and looks like a solid

ball of stars. One final cluster observation

was of M71, a moderately loose cluster

with a good range of stellar magnitudes.

Dave also sent in colour

images showing M27 and

M57. M27, the famous

Dumbbell Nebula, has a

beautiful blue/green and

pink/red colour and the

central star is well seen.

M57, the equally famous

Ring Nebula, is very well

exposed and again has good

colour; its central star and a

fainter one within the ring

itself is seen. The image is

shown in colour on p47. One

final observation from Dave is

of the recent Nova Delphini;

although no details of a magnitude

were given the image is of a high

magnification and shows it very well.

Our final report is from Eddie

Carpenter. Using 10×50 binoculars he

observed Nova Delphini, which was

visible as a faint star in a 6° field,

although no magnitude estimate is given.

One final note. Due to work and other

commitments I have decided to stand

down from the section, so this will be my

final report. Please hang on to your deep-

sky observations until a new director has

been appointed. If anyone would like to

take on the role, please contact myself or

Guy Fennimore; contact details on p46.

Darren Bushnall

Left: Dale Holt’s observational drawing

of the small, compact globular cluster

NGC 6642 in Sagittarius.

Cheeseburger on chips

Deep-sky

Section reports

Below: Dave

Finnigan

took this

splendid

image of

M27, the

Dumbbell

Nebula, a

large planetary

nebula in

Vulpecula.

The ‘Cheeseburger Nebula’

(NGC 7026), observed

by Dale Holt.



Comets I hope you will get up early in the

morning of 1 December to see the tail of a

Great Comet stretching across the sky.

That is what the hype on the Internet

surrounding comet 2012 S1 (ISON)

suggests that you will see, but does the

evidence bear this out?

Magnitude observations to date follow

the comet from 5.4 to 2.0 au on its way to

perihelion at 0.01 au. This sounds as if it

may be more than half way there, but

when we look at comet magnitudes we

need to take the logarithm of the distance,

and on this scale it has only moved from

0.73 to 0.30, and has to get to -1.91, so

there is a long way to go yet. The

consequence of this is that small errors in

magnitude estimates, combined with

differences between observers and

observing techniques combine to give

quite a large uncertainty in the peak

magnitude at perihelion. Whilst the

indications are that the comet may get as

bright as Venus, it could get brighter, or it

could be as faint as 4th magnitude.

Beware any Internet predictions that you

see that don’t mention error bars!

If the comet behaves according to the

most likely estimate we will have a comet

with a pretty long tail that will be worth

getting up for. On the other hand, the

worst case will be that it dies on the way

in to perihelion and there will be nothing

to see by early December.

We could still be in for surprises. The

comet passes within the solar Roche limit,

the distance at which a body held

together by its own gravitational pull

disintegrates. If the comet is fragile it

might therefore fragment and expose a

large area of fresh material that would

lead to a huge outburst in brightness.

Some people have called 2012 S1

(ISON) a Sun-grazing comet. Many of the

real Sun-grazing comets of the Kreutz

Group actually kiss the surface of the Sun

at 0.0046 au, whereas comet ISON only

gets to 0.012 au, which is close but

nowhere near the surface. It is better to

call it a Sun-skirting comet, though this

name is also associated with comets of the

Machholz Complex.

An explanation of these two

names is in order. The Kreutz

Group of comets was first

recognised by Heinrich Kreutz

at the end of the 19th Century

when he suggested that some of

the spectacular comets with

small perihelion distances, and

retrograde orbits with an

inclination of around 144°, were

related. Comet ISON is not a

member of this group. The

Machholz Complex is named

after comet 96P/Machholz and

studies of its orbital evolution

show that this comet is linked to

the Marsden and Kracht comet

groups seen by the SOHO

spacecraft, the daytime Arietid

meteors of June, the southern

Delta Aquarid and the

Quadrantid meteors, asteroid

2003 EH1 and possibly comet

1490 Y1.

There are also suggestions

that a meteor shower might be caused by

comet ISON. This is very unlikely. For a

spectacular meteor shower to occur the

Earth would have to pass close to the

debris trail laid down by the comet, and

which we initially see as its tail. The

Earth does pass 0.02 au from the orbit of

comet ISON in 2014 January, but

unfortunately it is nowhere near the

comet or its dust trail at the time.

Even if comet ISON doesn’t perform,

there are a few other comets around.

2P/Encke comes around every 3.3 years,

and this year the return favours the

Northern Hemisphere. The comet often

has a large and diffuse coma, and

although it may get to easy binocular

brightness, you will need dark skies to

spot it. Ideally use large binoculars rather

than a telescope, as the lower

magnification often does better.

Another periodic comet returns, though

154P/Brewington will be a telescopic

object of around 10th magnitude. Possibly

the most likely to be seen is another

discovery by Terry Lovejoy, designated

2013 R1 (Lovejoy), which could become

a binocular object, moving rapidly below

the Plough when brightest in November.

Keep an eye on the section web page at

www.ast.cam.ac.uk/~jds for updates.

Hopefully 2012 S1 (ISON) will put on a

spectacular show and we’ll get some

superb images to grace the cover of

Popular Astronomy.

Jonathan Shanklin

Editor’s note: Thanks to the vigilance of

Oliver Greenwood, a mistake was spotted

in my graphic of the tracks of comets

Encke and ISON in the Sep-Oct issue of

Popular Astronomy at the bottom of p45.

The comet labels are the wrong way

round; the top track is actually that of

Encke’s Comet, while the lower track is

ISON’s. The graphic at the top of p45 is

correct. Sorry for the confusion! PG

Will C/2012 S1

(ISON) be the comet

of the century?

Section reports

Comet ISON imaged on 8 October

with the 32-inch Schulman

Telescope at Mount Lemmon,

Arizona. Credit: Adam Block /

Mount Lemmon SkyCenter /

University of Arizona.

Left: ISON wasn’t quite bright

enough to be seen through 10×50

binoculars at this stage.



Reports, news and notesfrom the Society forPopular Astronomy

THE SPA’s year

of special

events to celebrate our

Diamond Jubilee

continued with a

splendid weekend of

events in Belfast.

The society made its

first ever trip across the

water to Northern

Ireland for what was

originally intended to be a day-long

meeting on 21 September at Queen’s

University.

But our hosts at the university

turned the event into a wonderful

weekend for members who travelled

from the mainland by plane or boat to

attend, joined by members of the Irish

Astronomical Association.

An excellent day of talks was

organised by Professor Alan

Fitzsimmons of Queen’s in a brand

new lecture theatre. Presentations

included latest results on

the Sun, techniques to

find protoplanetary

discs, the sky as

seen from Mars,

new ways to spot

exoplanets and

what causes

supernova

explosions.

Highlights came

with the final two

talks. Alan

Fitzsimmons

presented his

predictions for the behaviour of

incoming Comet ISON—a forecast

that rapidly swept the world thanks

to social media—and then our former

president Professor Iwan Williams

spoke on meteors and fireballs with

the latest information about

February’s Chelyabinsk bolide.

A great day ended with a highly

enjoyable meal at a local Italian

restaurant. But there was more to

come. The organisers had laid on a

coach trip to Armagh on Sunday to

visit the historic Armagh Observatory,

where we were welcomed by its

Director Professor Mark Bailey.

We were further honoured with an

invitation to a lunch reception from

the Lord Mayor of Armagh, Robert

Turner. Cllr Turner revealed his

research into the SPA’s history as he

recalled that the first director of the

Armagh Planetarium had been one of

the society’s founders, Sir Patrick

Moore. Our president Professor Derek

Ward-Thompson thanked the Lord

Mayor for his warm welcome.

The society would like to

acknowledge the support of the Royal

Astronomical Society in making it

possible to hold these regional

meetings.

Paul Sutherland

The photo below shows the Lord

Mayor welcoming members to Armagh

Palace. Picture credit: John Merry.

Wonderful

weekend in

Belfast

The Society Pages



The Society PagesCome to the SPA meeting

on 25 January 2014

Citizen Science:

a Revolution in

Your BrowserA talk by

Dr Robert Simpson(Oxford University)

Dr Simpson is an astrophysicist

whose research involves

understanding how stars form.

He works at the Zooniverse, a

world-leading Citizen Science

platform. In this talk Dr Simpson

describes how

Zooniverse has the

potential to enable

everyone with access

to the Web to

perform

‘real’

science.

Astronomer Royal addresses

successful SPA Convention

THE SPA Convention

held on Saturday 12

October proved to be a

great success. Over 250

people enjoyed a day of

talks, exhibits by Section

Directors, trade stands,

plus solar observing and

telescope tours, thanks

to the usual impeccable

organisation by Guy

Fennimore and Barry

Turvey.

The highlight of the

day was the Sir Patrick

Moore Lecture, given this year by the

Astronomer Royal himself, Prof. the

Lord Rees. If you couldn’t make it

along, or simply want to watch the

talks by Lord Rees, Mark Hurn and

Nik Szymanek again, you can do so

online via our Meeting Videos page

at www.popastro.com.

Lord Rees ponders the

question: will the next

60 years see as many

advances as the

last 60? Image

from video by

John

Chapman-

Smith.

Explore the

Universe in

Cardiff

TALKS by top cosmologists and

astrophysicists are a feature of

the SPA’s special Cardiff meeting

on 7 December 2013.

The meeting, to be held at Cardiff

University, is the last in a series

held around the country to

celebrate the society’s 60th year.

Speakers and subjects include:

Prof Matt Griffin, The European

Space Programme.

Dr Enzo Pascale, Balloon-borne

Astronomy.

George Ford, Multi-wavelength

astronomy.

Profs Steve Eales & Jon Davies,

The Dark Matter Debate.

Though admission to the meeting is

free to both SPA members and non-

members, we require attendees to

register with us in advance. Please

email your name, address and SPA

membership number (if any) to

[email protected].

The trade/display section.

The SPA 60th anniversary cake,

created by Barry Turvey.

Guy Fennimore at the well-stocked

SPA merchandise stand. All

images by John Chapman-Smith.



Sat 7 December 2013. SPA 60th anniversary event.

Welsh Regional Meeting, Cardiff University. See page

opposite for more details.

Sat 25 January 2014. 2 pm, Khalili Lecture Theatre,

School of Oriental & African Studies. Our main speaker

will be Dr Robert Simpson (Oxford) on The

Zooniverse—turning everyone into a scientist. Following

the break, Robin Scagell will describe what’s coming in

the night sky, and James Hilder will show us how much

of the southern hemisphere skies you can view from the

UK—including some amazing observations made from a

rooftop just yards away from our meeting place! For the

latest society news and info, see www.popaastro.com

Please note:

meetings start at

2pm and end at

5pm

SPA meetings to come

SPA statement on threat to The Sky at Night

FOLLOWING reports that the BBC

may be considering closing down

The Sky at Night TV programme, a

petition has been started to try to save

the programme. The SPA has also

issued an official statement giving its

views.

It has emerged that the BBC will be

‘discussing the future of the

programme’, which has been running

since 1957. It is scheduled to run until

December, after which its future is

uncertain. While the discussions could

be no more than a regular review,

which one would expect to happen with

every programme from time to time,

some people regard this as BBC jargon

for closing the show.

A group of students at the Open

University, led by SPA member Karen

Barker, have started a petition about

the programme, which at the time of

writing has over 35,000 signatures.

While acknowledging that a review

does not necessarily mean that the

programme will be cut, it specifically

requests that the style of the

programme not be changed. The

petition states:

‘We want to see The Sky at Night

continue in much the same way as it

always has: pitched in a scientific

manner towards people who are

knowledgeable on the subject, whilst

retaining its accessibility for newcomers

to the hobby with items aimed at them.

We believe that it should be presented

by professional scientists and/or highly

regarded amateurs, bringing the latest

news and information on the subject to

the people who want it. We do not want

to see it fronted by a generic television

presenter, or a ‘celebrity’ with no

connection to the hobby. It is a

specialist, scientific programme and

should be treated as such and with

respect to its origins and longevity.’

The story has been covered in the

national press, such as a very

sympathetic piece in The Scotsman by

Fiona McCade. who concludes, ‘The

BBC would be mad to let The Sky at

Night go, which means that it probably

will.’

Anyone who wishes to add their name

to the petition can do so at

www.change.org/en-GB/petitions/the-

bbc-please-do-not-axe-the-sky-at-night.

Please note that this will result in your

receiving emails about other campaigns

though you can then unsubscribe from

these. There is a Facebook group for the

petition but note that you need to be

registered with Facebook to view this.

On 1 October the SPA issued the

following statement:

‘The Sky at Night television

programme has been a source of

inspiration to all who have watched it

since its inception in 1957. It has

encouraged an interest in scientific

topics beyond just astronomy, from

people in all walks of life. Many of

today’s scientists gladly state that they

owe the awakening of their interest in

science to this programme.

The Society for Popular Astronomy

strongly exhorts the BBC to continue

this programme beyond the current

planned schedule of December 2013.

The ratings for this programme have

continued to be high, even after Sir

Patrick Moore sadly passed away last

year. The popularity for this

programme and this subject remains

undimmed. The BBC has a treasure in

this programme, which it would be

reckless to squander.

Furthermore, the SPA also strongly

urges the BBC to maintain the current

format of the programme. The

astronomical community is unanimous

in its belief that the style of this

programme is what has made it last for

so long. Its current presenters have

continued to cover a wide range of

astronomical topics in a style which is

accessible to a general audience while

not compromising the underlying

science or trying to over-simplify it.

The success of many other specialist

programmes, such as Springwatch or

Gardeners’ World, is due to the same

general approach—using presenters

who know their subject and are able to

take the audience with them into the

heart of the subject. We trust that the

BBC will see fit to continue The Sky at

Night in its current format.’

Robin Scagell

SPA Vice-President

The Society Pages

SPA meetings are usually held on the last

Saturday of January, April, July and October

in the Khalili Lecture Theatre of the School of

Oriental and African Studies, University of

London, Thornhaugh Street, Russell Square,

London, WC1H 0XG. Meetings start at 2pm and

last until 5pm, including a break for

refreshments. Members and their friends are

welcome, entry is free and there’s always a

friendly atmosphere. Members should remember

to bring their membership card or a copy of PA.

Directions to the venue: When you leave Russell

Square station, turn left and cross the road

straight away. SOAS is on the far corner of

Russell Square. Use the entrance marked,

opposite the Brunei Gallery. When you enter the

SOAS building, sign in as a visitor to the

university at the reception desk, where you will

be given a visitor sticker which you should keep

visible, and go through the entry gate. The

Khalili Lecture Theatre is downstairs—look for

the SPA signs. We also have our own signing-in

book before you enter the lecture theatre.



Sky Diary

Moon phases

Meteor notesNovember. The Taurids produce

observed rates of a few meteors per

hour in the first half of November.

Moonlight will hinder evening sky

observations after the first week.

The Leonids peak on 17 November,

but observing circumstances are very

unfavourable this year with full Moon

also occurring on the 17th.

December. The Geminids, the most

active meteor shower of the year, are

active from around 5 to 16 December,

with peak rates (ZHR over 100)

predicted for the night of 13-14

December. Unfortunately observations

of this year’s Geminid maximum will

be seriously hindered by a bright

gibbous Moon in Aries which will be

high in the evening sky and will not

set until around 05h.

The Ursids start close to the date of

full Moon, but slowly become more

favourable and will produce peak

observed rates of a few meteors per

hour around 21-23 December.

Additional information about meteor

activity during this period can be

found at

www.popastro.com/meteor/reference

/meteorshowers/ index.php.

Tony Markham

Apsides

OccultationsReappearance

Disappearance

Dark limb

Bright limb

The position angle (PA) of theoccultations given below is

measured anticlockwise from thenorthpoint of the Moon’s disc (usethe Moon’s north pole as a guide).

Date Object Mag Phase Data for Greenwich Data for Edinburgh

Time Alt° Az° PA° Time Alt° Az° PA°

10 Nov 46 Capricorni 5.1 DD 19h 16m 29 194 84 19h 11m 25 189 73

19 Nov NGC 1647 star 6.0 RD 01h 58m 55 207 247 01h 54m 52 198 261

19 Nov 97 Tauri 5.1 RD 05h 03m 33 259 276 04h 53m 35 251 285

22 Nov Lambda Geminorum 3.6 DB 00h 22m 41 120 147 00h 16m 37 118 129

22 Nov Lambda Geminorum 3.6 RD 01h 15m 48 135 230 01h 22m 44 136 248

24 Nov 60 Cancri 5.4 RD 01h 59m 38 125 346 Appulse

11 Dec Epsilon Piscium 4.3 DD 22h 16m 36 230 95 22h 07m 35 222 79

14 Dec Sigma Arietis 5.5 DD 02h 39m 18 272 84 02h 32m 21 266 74

21 Dec 50 Cancri 5.9 RD 06h 00m 35 243 326 05h 47m 36 233 331

22 Dec Omega Leonis 5.5 RD 02h 32m 46 161 262 02h 30m 41 157 272Note: These are the only occultations for this period, based on the criteria below. More information, see Occultation Section report.

Mag: Visual magnitude. Phase: (R)eappearance, (D)isappearance or (G)raze at (D)ark or (B)right limb of the Moon. Alt: Altitude. The Moon’s height at the time of the

occultation. Az: The angular position along the horizon measured clockwise from true north (through E, S, W back to N). PA: Position Angle of the event, measured

anticlockwise from the direction of the Celestial North Pole. This listing shows lunar occultations of stars brighter than mag +6, observable with small telescopes in a sky dark

enough to be seen without difficulty. Specific data for your own locality or for details of fainter occultations, contact Occultation Section Director Mell Jeffery (address on p46).

Date Apsis Dist (km) Size

6 Nov, 9h Perigee 365,361 32’ 42”

22 Nov, 10h Apogee 405,445 29’ 29”

Date Apsis Dist (km) Size

4 Dec, 10h Perigee 360,063 33’ 11”

20 Dec, 0h Apogee 406,267 29’ 25”

New First quarter Full Last quarter

3 Nov, 12:50 10 Nov, 05:57 17 Nov, 15:16 25 Nov, 19:28

3 Dec, 00:22 9 Dec, 15:12 17 Dec, 9:28 25 Dec, 13:48

270°

180°

0°

90°

A summary of sky eventsfrom November to

December 2013 (UT times)

Comets ISON and Encke, November

This chart shows the path of both comet 2P/Encke and C/2012 S1 (ISON)

throughout November at daily intervals. Also marked is the daily path of the

Sun and the positions of Mars, Mercury and Saturn on 15 November. PG.

1 Nov

1 Nov

30 Nov

30 Nov30 Nov



Solar SystemMercury makes its best appearance of

2013 during November. Following

inferior conjunction on 1 November, the

planet quickly heads west of the Sun

and emerges into the morning skies.

Mercury can be spotted quite easily

with the unaided eye throughout the

latter part of November, given a

clear, flat east/southeastern horizon.

Greatest elongation west takes place

on 18 November, when it is 20° from

the Sun; it rises at around 04:40, almost

two hours before sunrise, has climbed to

5° by the end of astronomical twilight and

is 15° high at sunrise. At mag. -0.5, Mercury

is 6.7 arcsec. across and 60% illuminated at this

maximum elongation.

Comet Encke (mag. +4.6) lies just over 1° southwest of

Mercury on the morning of 18 November, both visible in the

same low-power telescopic field for a few days around this

time. Another close Mercurian encounter takes place on 26

November, when it passes within ½° south of Saturn (mag.

+0.6). This will be a delightful scene through a telescope with

an eyepiece that holds both planets in the same field.

As it draws closer to the Sun the planet is effectively lost to

view from the end of the first week of December. Superior

conjunction takes place on 29 December.

Venus has been loitering in the skies east of the Sun since

the spring, but its low elevation at sunset hasn’t allowed it to

show off. Venus’ greatest elongation east takes place on 1

November, 47° from the Sun and shining at mag. -4.4.

Measuring 25 arcsec. in apparent diameter, Venus’ dichotomy

(half-phase) occurs around this time. Heading back towards

the Sun, its apparent size increases as it becomes ever more

crescent-shaped. By the end of November it is 37 arcsec.

across, 31% illuminated and shines a brilliant mag. -4.6. By

the year’s end Venus is mag. -4.4, some 10° high at sunset,

and telescopically appears a large (59 arcsecond) but narrow

(4% illuminated) crescent.

Mars treks from mid-Leo into western Virgo

during November and December, a

continually improving morning object

steadily increasing in brightness and

apparent size. Mars has grown larger

than 5 arcsec., large enough to be

considered worthy of serious telescopic

study and CCD imaging. At the end

of November Mars is 72° west of the

Sun, rising at 01h, and is 38° above

the south-eastern horizon by the end

of astronomical night.

On 17 November at around 03h Mars

passes close to Sigma Leonis (mag.

+4.0), the pair being separated by just 35

arcseconds—tough to split in binoculars.

By the end of December the Red Planet

shines at mag. +0.9; rising at around 00:30 it

transits the meridian at an altitude of 37° nearly two

hours before sunrise. Now 6.8 arcsec. across, observable for

3½ hours against an astronomically dark sky at more than

20° high, it’s time to refamiliarise ourselves with Mars, its

fascinating features and nomenclature.

Jupiter continues its rise in the late evening/early morning

skies. Located in mid-Gemini, the planet brightens from mag.

-2.4 to -2.7 and its apparent diameter increases from to 41 to

47 arcsec.during the course of November and December. At

the beginning of December Jupiter rises at 19h and transits

the meridian at 03h, some 60° high. Things have improved

yet further by the year’s end, when it rises at 17h and

transits at 01h; by 06h, near the end of astronomical night it

is 20° high. This means that Jupiter can be followed at a good

altitude in a dark sky for more than 10 hours, enabling an

entire rotation of the planet to be observed in a single night.

Saturn undergoes conjunction on 6 November. It begins to

emerge in the morning skies within a few weeks.

Uranus (mag. +5.7, 3.4 arcsec. across) and Neptune (mag.

+7.8, 2.4 arcsec. across) are both evening objects in Pisces and

Aquarius respectively.

The path of Comet

Brewington through

Pegasus plotted at

daily intervals

between 1 November

and 31 December.

The comet will be a

9-10th magnitude

binocular object at

its best in late

November.

Sky Diary

December—ISON

heads north

Comet 154P/

Brewington

The northward path of

Comet ISON during

December, plotted at

daily intervals between

1 and 31 December.1 Dec

31 Dec

26 November—

Mercury and

Saturn.



Observing Section DirectorsOfficersSecretary

Guy Fennimore

36 Fairway

Keyworth

Nottingham

NG12 5DU

[email protected]

Membership Secretary—

enrolments, renewals and

changes of address

Barry Turvey

36 Fairway

Keyworth

Nottingham

NG12 5DU

[email protected]

Treasurer

Helen Walker

38 Edwin Road

Didcot

OX11 8LE

[email protected]

Webmaster

[email protected]

Popular Astronomy Editor

Peter Grego

7 Parc-An-Bre Drive

St Dennis

St Austell

PL26 8AS

[email protected]

Publicity Officer

Mandy Bailey

22 Christine Avenue

Wellington

Telford

TF1 2DX

[email protected]

SPA Council Members

Paul Millington

Ian Morison

Margaret Penston

John Chapman-Smith

Paul Sutherland

Weekend Course Organiser

Guy Fennimore

36 Fairway

Keyworth

Nottingham

NG12 5DU

[email protected]

SPA Advisory Services

Patron: Professor Sir Arnold Wolfendale, FRS, 14th Astronomer Royal

Society for Popular Astronomywww.popastro.com

President: Prof Derek Ward-ThompsonJeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE [email protected]

Vice Presidents: Prof Ian Robson [email protected] / Robin Scagell [email protected]

Aurora Sandra Brantingham, Trevona, Glenbarry, Banff, AB45 2HJ

[email protected] Website: www.branters.freeserve.co.uk/

Comet Jonathan Shanklin, 11 City Road, Cambridge, CB1 1DP

[email protected] Website: www.ast.cam.ac.uk/~jds/

Deep Sky Darren Bushnall, 270 Owton Manor Lane, Hartlepool, TS25 3RL

[email protected] Website: homepage.ntlworld.com/darren.bushnall/

Lunar Peter Grego, 7 Parc-An-Bre Drive, St Dennis, St Austell, PL26 8AS

[email protected] Website: www.lunarobservers.com

Meteor Tony Markham, 20 Hillside Drive, Leek, ST13 8JQ

[email protected]

Occultation Mell Jeffery, 11 Chestnut Grove, Norton, Malton, YO17 9BZ

[email protected]

Planetary Alan Clitherow, Coldene, Bridgend, Ceres, Cupar, KY15 5LS

[email protected]

Solar Geoff Elston, 59 Nalders Road, Chesham, HP5 3DQ

[email protected]

Variable Star David Scanlan, 87 Withy Close, Romsey, SO51 7SA

[email protected]

Young Chief Stargazers, George Ford and Ezzy Pearson

Stargazers [email protected]

The SPA section directors are happy to help members with all aspects of

observing. Many sections have their own printed leaflets and observing

forms which can be obtained by post or via the SPA website at

www.popastro.com.

Please send your astronomical observations (notes, observational drawings

or images) to the section directors by post or by email attachment. The SPA

advisors are happy to answer questions about their own astronomical

specialties. If using regular mail, please enclose a suitably sized stamped,

self-addressed envelope when corresponding with directors and advisors.

Astronomy Tony Sizer, 88 Cumberland Avenue, Welling, DA16 2PU

GCSE [email protected]

Astro Imaging Nik Szymanek, 186 Thorndon Avenue, West Horndon, Brentwood, CM13 3TP

[email protected] Website: www.ccdland.net

Cloud Watch Terry Holmes, 34 Sycamore Road, Tipton, DY4 9RN

[email protected]

Instrument Ian Morison, 4 Arley Close, Macclesfield, SK11 8QP

[email protected]

Light Pollution Martin Morgan-Taylor, 39 Sports Road, Glenfield, Leicester, LE3 8AL

Liaison Officer [email protected]



Celestial rings

RING structures abound in the

Universe, and here are some

lovely, easily observed examples.

At top is Mike Brown’s image of

one of the most spectacular areas on

the Moon—the region bounding the

northwestern shore of Mare

Nectaris, with craters Theophilus,

Cyrillus and Catharina. Victorian

astronomers liked to call such large

craters ‘ring mountains’.

At centre is the unmistakable

ringed planet Saturn, imaged by

Martin Lewis (see Planetary Section

report on p38 for details).

To the right is the famous Ring

Nebula (M57) in Lyra, imaged by

Dave Finnigan (see Deep Sky Section

report on p39 for details). Dave Finnigan

Martin Lewis

Mike Brown



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Celestron®, SkyQTM and StarSenseTM are trademarks or registered trademarks of Celestron Acquisition, LLC in the United States and in dozens of other countries around the world. All rights reserved. David Hinds Ltd is an authorised distributor and reseller of Celestron products. The iPhone® and iPad® are trademarks of Apple Inc., registered in the U.S. and other countries. AppStore is a trademark of Apple Inc.

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Documents

Society for Popular Astronomy November …popastro.com/documents/PA_2013-1112.pdfThe bimonthly magazine of the Society for Popular Astronomy November-December 2013 ... (e.g. October