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Journal of the Amateur Astronomers Association of New York
September 2016 Volume 65 Number 9; ISSN 0146-7662
Setting a New Course with AAA’s First Night Sky Photography Class
By Stan Honda
In June, I had the pleasure of leading the first-ever
Night Sky Photography Class for AAA, and judging by
the images the students produced, I can safely say that
they are well on their way to being excellent astrophotog-
raphers.
The course consisted of four classroom sessions plus a
fieldtrip to photograph the summer Milky Way. Three classes
were held at the Cicatelli Center in Manhattan, and a fourth,
informal session took place at a nearby restaurant. For the
fieldtrip, we visited the United Astronomy Clubs of New Jer-
sey (UACNJ) observatory site at Jenny Jump State Park
30 students signed up for the class, and during the course
they learned how to shoot wide-field pictures of the sky and to
combine those shots with landscape features – all using an
ordinary digital camera and a wide-angle lens.
In class, I covered the basic steps of night sky photog-
raphy, including composition, camera settings, correct expo-
sure, proper equipment, and how to plan a shot. I also demon-
strated image processing of photos using programs like Pho-
toshop. For homework, students photographed the night sky
from the urban neighborhoods where they live, and some trav-
eled outside the City to try out the new techniques.
The trip to Jenny Jump was certainly the highlight of the
class. About 17 students made the drive out on a warm Satur-
day in July. The UACNJ site is an excellent location both for
observing and photographing the night sky. AAA is a mem-
ber of the UACNJ, a consortium of 11 area clubs, so Jenny
Jump is open to all AAA Members. To learn more about ob-
THIS MONTH: Fall Astronomy Class Begins Sep 7, Lecture Series Sep 30, and Annual Urban Starfest Oct 1
FOCUS ON THE UNIVERSE
Digging into Data to Answer, “Are We Alone in the Universe?”
By Harriet Brettle
“Two possibilities exist: either we are alone in the Universe
or we are not. Both are equally terrifying.”
– Arthur C. Clarke
On June
13, a panel of
physicists and
philosophers
met at the New
York Academy
of Sciences to
discuss a fun-
damental ques-
tion for both
fields: Are we
alone in the
universe? The speakers included Adam Frank, Professor of Phys-
ics and Astronomy at the University of Rochester; Louisa
Preston, astrobiologist, planetary geologist and author; Ste-
phen M. Gardiner, Professor of Philosophy at the University
of Washington; and Jason Thomas Wright, Associate Profes-
sor of Astronomy and Astrophysics at Pennsylvania State
University.
The talk began at its most natural starting point with the
introduction of the famous 1961 Drake equation, a simple
formula to estimate the number of active, communicative ex-
traterrestrial civilizations in the Milky Way. That number, N,
takes into consideration the factors that must be in place for
such civilizations to exist. For N = R* · fp · ne · fl · f i · fc · L
R* = average star formation rate,
fp = the fraction of those stars with planets,
ne = average number of habitable planets per star with planets,
fl = the fraction of habitable planets that develop life,
fi = the fraction of planets that develop intelligent life,
fc = the fraction of civilizations that develop technology that
release detectable signs of their existence into space, and
L = the length of time that civilizations produce detectable sig-
nals into space
Today, this equation has moved from the realm of science
Are We Alone? (cont’d on Page 4-5) AAA’s Night Sky Photography Class (cont’d on Page 4)
ASTRONOMY TALKS
Preston Stahly
The Milky Way over the valley at Jenny Jump State Park.
SETI
In 1961, Frank Drake developed the Drake Equa-tion to estimate the probable number of extrater-restrial civilizations with communications technol-
ogies in our Milky Way galaxy.
NASA
This month, NASA launches OSIRIS-Rex, its first asteroid sample-return mission.
The spacecraft will arrive at Bennu in 2018 and create a 3-D map before harvesting
surface material to return to Earth in 2023.
2
September’s Evening Planets: Jupiter will be in Vir-
go the Maiden for an hour during the first half of September.
Mars will be between Scorpius the Scorpion and Sagittarius
the Archer until 11 PM. Saturn will be in Scorpio until 11
PM and setting earlier each night until 10 PM by the end of
the month. Bright Venus will be in Virgo after sunset until
about 8 PM. Uranus will be in Pisces the Fish and Neptune
is in Aquarius the Water Bearer all night. Dwarf planet Pluto
is in Sagittarius until midnight.
September’s Evening Stars: Spot the Summer Trian-
gle of Vega in Lyra the Harp, Deneb in Cygnus the Swan,
and Altair in Aquila the Eagle. See Antares in Scorpius and
Arcturus in Boötes the Herdsman until 10 PM. Look for
Capella in Auriga the Charioteer around 10 PM, lingering all
night. Find the stars of constellations Andromeda, Cassiope-
ia, Pegasus, Perseus, Hercules, Draco, Sagittarius, Aquarius,
Pisces, Capricornus, and Ursa Major and Ursa Minor (the
Big and Little Dippers).
September’s Morning Planets: Uranus will be in
Pisces and Neptune can be found in Aquarius. Mercury will
be between Leo the Lion and Virgo beginning at 5 AM in the
second half of the month.
September’s Morning Stars: Sirius, the brightest star
from Earth, will be up around 4 AM each morning and rising
earlier by 2 AM at the end of the month. Spot Capella in
Auriga and the stars of Aquarius, Cetus, Taurus Gemini, Ori-
on, Pisces, Andromeda, Cassiopeia, Aries, Draco, Cygnus,
Pegasus, Perseus, and the two Dippers.
Sep 1 New Moon 5:05 PM
Sep 6 Moon at apogee (251,700 miles away)
Sep 9 First Quarter Moon 7:50 AM
Sep 16 Full Moon 3:05 PM
Sep 18 Moon at perigee (224,900 miles away)
Sep 21 Mercury stationary 6:00 AM
Sep 22 Autumnal equinox 10:21 AM
Sep 23 Last Quarter Moon 5:55 AM
Sep 25 Pluto is stationary 11:00 PM
Sep 28 Mercury at greatest western elongation
Brightest Mercury of 2016 - predawn
Sep 30 New Moon 8:11 PM
Times given in EDT.
WHAT’S UP IN THE SKY
September 2016
Break Me Off a Piece of that Asteroid
This month, NASA will send the first probe to an asteroid
that will bring back to Earth some of its dust. The spacecraft
OSIRIS-REx is scheduled to launch from Cape Canaveral,
FL on September 8 aboard an Atlas V rocket, and it will re-
turn home in 7 years with a sample of the asteroid Bennu.
The Mission OSIRIS-REx will
orbit the Sun for a
year and then
make a flyby of
Earth to use its
gravitational field
as a slingshot
towards Ben-
nu. The probe
will begin its approach in Aug 2018, when it will brake to
match Bennu’s velocity as it orbits the Sun. OSIRIS-REx
will fly in formation with Bennu, surveying and mapping the
asteroid and studying its geology to select a sample site.
On Jul 4, 2020, OSIRIS-REx will extend the Touch-And-Go
Sample Acquisition Mechanism (TAGSAM), a robotic arm
with a sampler head, to collect regolith (surface material). It
will touch Bennu for five seconds and release a burst of ni-
trogen gas to stir up the soil, forcing dust into a collector that
holds up to 4.4 pounds. The dust is deposited into a Sample
Return Capsule onboard the spacecraft. The probe will then
wait until Mar 2021 to start the trip back to Earth, where it
will jettison the capsule and deflect itself into solar orbit.
The capsule will land in the Utah desert on Sep 24, 2023.
Why Bennu? 101955 Bennu, also known as 1999 RQ36, is a 500 meter-
diameter, potentially hazardous near-Earth asteroid that trav-
els 63,000 mph as it orbits the Sun every 1.2 years. It was
selected because of its proximity and its orbit of low eccen-
tricity and inclination. Its size also lets it spin slowly enough
for a probe to collect a sample. A rare, primitive, carbon-rich
asteroid with organic compounds, Bennu has not changed
much since forming over 4 billion years ago, and it may con-
tain the precursors of life on Earth.
What Does OSIRIS-REx Stand For? OSIRIS-REx is an acronym of the mission’s main goals and
mimics the name of the ancient Egyptian god Osiris. Its full
name is: Or igins Spectral Interpretation Resource Identi-
fication Secur ity Regolith Explorer .
Who are Osiris and Bennu in Egyptian Mythology Osiris is the god of afterlife, resurrection, and regeneration.
His wife and sister, Isis, famously used magic to restore him
after he was murdered by his brother, Set. Osiris judges the
dead and grants all life, even the fertile flooding of the Nile
River. Bennu is a bird deity associated with Osiris. A sym-
bol of creation and rebirth, it may have inspired the Phoenix
in other cultures. It lives on the sacred tree of life.
Sources: nasa.gov; asteroidmission.org; Encyclopedia Britannica.
Follow veteran sky watcher Tony Faddoul each month, as he points our minds and our scopes toward the night sky.
AAA Observers’ Guide
By Tony Faddoul
September “Skylights”
NASA
OSIRIS-REx with its robotic arm extended to take a sample at the asteroid Bennu.
3
September 2016
Getting the Timing Right When Taking a Fieldtrip with AAA
By Peter Tagatac
Event schedule changes are disruptive and a bummer
for those wanting to attend an observing trip but who ulti-
mately cannot go. It' s hard not to feel bad, or even re-
sponsible, despite the fact that Mother Nature is the one call-
ing the shots. During the summer and fall, AAA plans month-
ly overnight fieldtrips to visit the dark skies at North-South
Lake in the Catskill Mountains region, but sometimes the
schedule changes as forecasts are updated. Many had to fore-
go the last trip, which was moved a day earlier to Friday, July
29, but AAA has three more opportunities available with
weekends scheduled in the coming months. We hope you’ll
join us for one of these.
Despite the re-
scheduling, things
turned out well for
those who could
make it in July. 15
observers in six cars
met in the parking lot
of the Lake’s
campgrounds. The
sky was mostly clear
throughout the night
from Civil Twilight
to about 3:00
AM, when the last
car left. There were
some clouds and
haze, but that did not
take away from the
theatre of light above
our heads.
Comets fre-
quently shot across
the bow with a few
lighting up the
sky to audible
gasps from ob-
servers on the
ground. Satel-
lites, planets,
naked-eye deep
sky objects, and
the Milky Way
all showed up.
Imagination-
defying close-ups
of open and glob-
ular clusters,
planetary nebu-
lae, and galaxies,
frequently ap-
peared in our
eyepieces.
Initially,
stratus clouds
rimmed the hori-
zon to the north-
east and south,
but those would
clear by Astro
Twilight. A slight haze attenuated the Milky Way brightness,
and the naked-eye limiting magnitude below 30° was about
5.3. Naked-eye objects easily viewed were the Double Clus-
ter, Andromeda Galaxy, Kemble’s Cascade, the Coathanger,
M7, M23, and M13. Binoculars and telescopes popped out
any object of interest.
The difference in observing city skies and rural skies is
remarkable. For most of the session, the viewing could be
rated a 7.5 for a visual observer, although perhaps a bit less
for an astrophotographer. Nevertheless, AAA President Mar-
celo Cabrera and AAA Member Harry Slotwiner were able to
capture some beautiful photos and videos. As these pics
demonstrate, the scheduling difficulties for the observing ses-
sion ultimately paid off, and it was definitely worth the trip!
To join AAA on an upcoming trip to this marvelous dark
sky location, contact Tom Haeberle at [email protected] .
AAA OUT OF TOWN
Marcelo Cabrera
The Milky Way is clearly visible amid the dark skies at North-South Lake. Two more fieldtrips are scheduled for the end of Sep and Oct.
Harry Slotwiner
The dark skies above North-South Lake in Haines, NY on July 29-30.
Harry Slotwiner
AAA Observers took a fieldtrip to North-South Lake in the Catskills on July 29-30.
Harry Slotwiner
AAA Member Harry Slotwiner created a time-lapse video using a Canon T5i and 18 mm lens, with processing in Lightroom. Take a look at https://www.youtube.com/watch?
v=Ahj7F6viF9E
4
September 2016
serving there, visit www.aaa.org/observing/uacnj-jenny-jump-
state-park/.
One of the better views at the Park is toward the south-
west, where the summer Milky Way appears once the sky
darkens. 70 miles from NYC, there is still some light pollu-
tion, but everyone was able to shoot nice photos of the stars
and our galaxy using a variety of styles and approaches.
Preston Stahly used a Rokinon 14mm fisheye lens,
adapted to his Sony a7Rii camera, to create a very wide view
of the sky and the valley below the Park. With a setting of
ISO 6400, 15 sec, f5.6, he captured the central part of the
Milky Way as it arches to the south, as well as the planets
Mars and Saturn in and around Scorpius. A couple of streaks
from airplanes show up along with light from NYC (left) and
nearby towns (center/right), but they aren’t distracting at all.
Chirag Upreti’s photo features a nice silhouette of sever-
al students against the sky, with the glowing screens of their
cameras visible. By choosing a low angle, Chirag used the
large rock where we stood to block the horizon and much of
the orange glow of artificial light to focus on the Milky Way
above. He used a Sony A6000 camera with a Rokinon 12mm
f2.8 manual lens and an exposure of ISO 3200, 10 sec, f2.8.
A few students created star trails that night. In Gowri
Lakshminarayanan’s photo, central Polaris is hidden in the
treetops, as stars rotate during a 30-min exposure. Gowri
used a Canon 5D Mk III camera with a 16-35mm f2.8 lens set
at 16mm. He shot 30 frames at a setting of ISO 800, 60 sec
per frame, with each frame spaced 1 sec apart. In StarStaX,
he combined the frames to make the trail image. Transferring
the final image to Photoshop, Gowri then darkened the fore-
ground foliage, which was over-lit by a car’s headlights.
View more student photos at www.aaa.org/gallery-2/
astrophotography/. Thanks to everyone for making AAA’s
inaugural Night Sky Photography Class such a success!
AAA’s Night Sky Photography Class (cont’d from Page 1)
fiction to reality. The discovery in recent years of thousands
of exoplanets orbiting other stars allows us to actually plug
some numbers into the variables, particularly the fraction of
stars with habitable planets. It is currently estimated that on
average, each star in our galaxy has one planet orbiting it.
Professor Frank spoke about his work, which inverts the
Drake equation to ask, “How unlikely is it that humanity is the
only civilization in the universe?” or, put another way, “ How
bad does the universe have to be for us to be alone?” He sets
a firm lower bound on the likelihood that one or more techno-
logical species have evolved at some point in history. If the
probability that a habitable zone planet develops a technologi-
cal species is larger than about 10−24, then other intelligent
civilizations must have evolved. That’s a pretty small number
to beat. And, the sheer number of stars in our galaxy gives us
good reason to expect there must be some form of life out
there beyond the pale blue dot we call home.
However, a high probability for the existence of extrater-
restrial civilizations creates an apparent contradiction. If
they’re out there, then where are they? Why haven’t they
swung by to say hello? According to Professor Wright, this
conundrum, known as the Fermi Paradox, is easily explained:
we simply haven’t been looking well enough or long enough.
After the pioneering work of Frank Drake, NASA began
a low-level search for extra-terrestrial intelligence (SETI) in
the late 1960s, but funding was dropped by the 1990s. These
days, the search is led by the SETI Institute, formed in 1984,
which relies on private funding. Now, Breakthrough Initia-
tives has joined the search. Established last year by Russian
entrepreneur Yuri Milner and his wife, its program of scien-
tific and technological exploration has committed $100 mil-
lion to the search for artificial radio and optical signals. (This
year, Breakthrough devoted another $100 million toward engi-
neering technology for ultra-light, ultra-fast unmanned space-
flight to the Alpha Centauri star system 4.3 light-years away.)
But even if we spend all our time listening to the stars,
will we know intelligent life when we hear it? As Arthur C.
Clarke once said, “Any sufficiently advanced technology is
indistinguishable from magic.” So, how can we differentiate
between super-intelligent life and some physics that we simp-
ly don’t yet understand?
Until we figure that out, we can only look for anomalies
Are We Alone? (cont’d from Page 1)
Chirag Upreti
AAA students silhouetted against the night sky.
Gowri Lakshminarayanan
Star trails above Jenny Jump State Park
NASA
Light curves like this from Kepler space observatory data show the presence of an exoplanet, which creates a dip in
a star’s brightness as it transits in front of it during orbit.
5
in our data. One recent example is the strange case of KIC
8462852 – a bright F-class star 1,500 light-years away in the
constellation Cygnus – observed by the Kepler space observa-
tory. Kepler has been in operation since 2009 and has discov-
ered thousands of exoplanets by analyzing the light curves of
stars. When a planet passes in front of a star, it blocks some
of its light, and a periodic dip in brightness over time demon-
strates its orbit. From these light curves, we can infer infor-
mation about the size of the planet and its orbit around the
host star. But KIC 8462852 (affectionately known as Tabby’s
star, after Tabetha Boyajian, the Yale professor who discov-
ered it) has a light curve that cannot be explained by an orbit-
ing planet or other natural phenomena.
The light curve for Tabby’s star, observed by Kepler
over 4 years, shows obvious downward spikes around Day
800 and Day 1500. These are much larger than normal dips in
magnitude for planet transits of a large star. Researchers con-
sidered a number of explanations for the light dips, including
variable stars, large dust clumps, catastrophic collisions, and
newly forming planets, but further analysis ruled all of these
out. The best natural explanation is a swarm of comets pass-
ing the star, but this theory is not widely accepted. Boyajian
has launched a Kickstarter campaign to secure telescope time
to conduct further observations. Meanwhile, the SETI Insti-
tute began its own search for signals, to investigate whether
KIC 8462852’s light dips may be caused by artificial struc-
tures orbiting the star, built by an advanced alien civilization.
Another explanation to the Fermi paradox is that we just
aren’t interesting enough for extraterrestrials to bother reach-
ing out to us. Louisa Preston pointed out that for most of hu-
man history, we haven’t been worth talking to – we have only
developed technology capable of communication in the last
100 years. Again, Arthur C. Clarke put it best: “I'm sure the
universe is full of intelligent life. It's just been too intelligent
to come here.”
Another significant consideration for the Fermi paradox
is the issue of timing. The Drake equation suggests that many
intelligent species do exist, but it does not indicate when they
exist. With only one data point for a technologically commu-
nicative intelligent species (us), it is difficult to know how
long a typical one would last. In human history, civilizations
have risen and fallen, but our species has found a way to con-
tinue and to advance. For all we know, life could be endless if
it were able to escape extinction-level disasters – an asteroid
strike, nuclear war, climate change, death of a home star – and
a highly advanced civilization with space flight capability
could do that. So, if life does not necessarily have an expiry
date, then it is reasonable to think that if we wait long enough,
August 2016
we will find another intelligent civilization out there. Using a
more conservative approach, we could estimate the lifetime of
a species to be 1,000,000 years, the average for mammals on
Earth, and that still far exceeds the lifetime of humanity so far.
We’ve only been intelligent enough to produce communication
signals for 0.01% of that time though. And if life in general
appears independently throughout the universe, then advanced
species may never overlap. Even if we do exist at the same
time, the vastness of space may keep our signals from reaching
each other before the clock runs out on one of our species.
The panel also engaged in an interesting discussion about
the implications for Earth if we were to detect extraterrestrial
life. Unless it was found to be really close (and not much can
be considered close for the distance scales of the universe),
then there’s not much to be done. Recently discovered Proxi-
ma b, the nearest exoplanet detected that resides in its star’s
habitable zone and perhaps supports liquid water, is about 4.2
light-years away. Even if a signal were received from such a
distance, the conversation is going to be pretty slow. The SETI
Institute does have a protocol for the discovery of an extrater-
restrial signal; however, it focuses on confirming the science of
the detection rather than the social or political implications of
contact. The United Nations Office for Outer Space Affairs
(UNOOSA) could play a role, but as of now, no concrete plan
have been established.
Instead of looking toward the
depths of the galaxy for life, Louisa
Preston suggests our efforts would be
better placed searching within our own
Solar System. Liquid water has been
found on Mars and is likely flowing
under the icy surface of moons like
Jupiter’s Europa – these are much
easier for us to reach. Even if life has
not evolved independently in these
places, it may have transferred be-
tween planets during periods of bombardment. Rocks from
Mars have been discovered in Antarctica, and it is likely that
meteorites from Earth have reached Mars. The transfer of mi-
crobes that could survive both the trip and the Martian environ-
ment is not completely impossible.
The talk ended with each speaker’s wish-list for devoting
resources to finding out whether or not we are truly alone.
Jason Wright supports increased funding of SETI. Given the
potential impact of a discovery, he believes it is well worth
dedicating time and money to looking for intelligent life. With
a current sample size of one, there is so little that we even un-
derstand about intelligent species and how they evolve. Adam
Frank would invest more in simulations and modeling of intel-
ligent life evolution to understand how life forms and what life
would actually look like on other worlds. This would help to
direct our search when scanning the skies.
The New York Academy of Sciences panel was thor-
oughly engaging, and all of the speakers were enthusiastic and
hopeful for the future. For the first time in our history, we are
on the cusp of finding a meaningful answer to the question,
“Are we alone?” using data and scientific inquiry. In the
words of Carl Sagan, who would have shared this optimism,
“Somewhere, something incredible is waiting to be known.”
Boyajian et al.
Sporadic dips in the light curve for KIC 8462852 as observed by Kepler over 4 years are not well explained by natural phenomena.
NASA/JPL/DLR
Jupiter’s moon Europa has a sub-surface ocean. Is it our best bet for find-ing life outside of Earth?
6
September 2016
Celestial Selection of the Month Fornax A
60 million light-
years away in the south-
ern constellation For-
nax is a monster of a
galaxy with a history of
gobbling up its neigh-
bors. The four th-
brightest radio source in
our sky, Fornax A is an
elliptical galaxy with a
supermassive black hole
of about 130 to 150 mil-
lion solar masses at its center. Inward falling gas at the black
hole is heated to up to 10 million degrees, hyper-fueled by gas
from past galactic mergers. At some point, oppositely point-
ing jets of particles shooting out from the accretion disk
around the black hole slammed into surrounding material to
form two giant lobes of hot gas that emit very strong radio
waves. For the past 100 million years, the galaxy, also known
as NGC 1316, has been consuming its spiral companion NGC
1317. Surrounding NGC 1316
is evidence of it’s appetite:
faint tidal tails are the shells of
stars it has torn from galaxies
and flung into intergalactic
space. NGC 1316 also shows
the battle scars of very old vio-
lence. Embedded within it are
dust lanes and small globular
star clusters that appear to be
remnants of a spiral galaxy
eaten 3 billion years ago.
AMW Sources: eso.org; nasa.gov.
Telescope of the Month The Square Kilometer Array and MeerKAT in South Africa
In the deserts of the Karoo in South Africa, the world’s largest radio telescope is
under construction, an array of thousands of dishes with a collecting area of one mil-
lion square meters. When completed in 2030, the Square Kilometer Array (SKA)
will be able to detect radio waves from objects that are millions or billions of light-years
from Earth. The sheer size of SKA makes it 10,000 times faster and 50 times more sensi-
tive than the best radio telescopes. Currently, the largest is the 305m-diameter Aricebo in
Puerto Rico; the Five-hundred-meter Aperture Spherical Tele-
scope in China just finished construction. Operating over a range of frequencies, with antennas laid out
in intricate mathematical patterns, the image resolution of SKA will exceed that of the Hubble Space Tel-
escope by a factor of 50. The South African desert is ideal for the array, far away from electronics that
interfere with the faint radio signals of the universe, and high and dry enough to avoid radio wave absorp-
tion by moisture in the atmosphere. SKA will have outstations throughout the continent, while a partner
array to detect low-frequency signals will be built in Australia. An international project headquartered at
the University of Manchester, SKA involves 100 organizations from 20 countries. To handle SKA data,
which will create more traffic than the entire internet, engineers are working on a super-fast supercomput-
er. The first phase of SKA builds off South Africa’s MeerKAT telescope, with 16 of its 64 dish antennas
now operational. In July, scientists announced that MeerKAT discovered over 1,200 new galaxies in a
patch of sky where only 70 were previously seen. Some show supermassive black holes at their centers,
spewing jets of material that emit radio waves. AMW Sources: ska.ac.za; nytimes.com; space.com.
SKA South Africa
MeerKAT in South Africa will become part of the Square Kilometer Array, the largest
radio telescope in the world.
SK/MeerKAT
A close-up of the first image by MeerKAT
shows a new galaxy, one of 1,200 discovered, with a black hole at its center.
Solar Sagas It’s Alive! Solar Storms Seeded Life on Earth
In May, NASA revealed that solar explosions 4 bil-
lion years ago may be responsible for life on Earth. Scien-
tists have struggled to explain how life could have evolved so
long ago, when Earth received only 70% of the energy from
the Sun that it gets today. Known as the Faint Young Sun
Paradox, Earth should have been a cold, icy rock back then,
but geological evidence indicates it was a warm, watery place.
Looking at similar stars in our galaxy and ordering them by
age, scientists created a timeline for our Sun’s evolution.
Kepler data shows that young suns have huge explosions, or
“superflares,” ejecting radiation into space. Today’s Sun has
a superflare once every 100
years, but in its youth, it like-
ly had 10 a day. And back
then, Earth had a weaker
magnetic field, leaving it vul-
nerable to the superflares’
energetic particles. “Our cal-
culations show that you would
have regularly seen auroras
all the way down in South Carolina,” said NASA’s Vladimir
Airapetian. Solar particles collided with nitrogen molecules,
which made up 90% of early Earth’s atmosphere, splitting
them up to then react with CO2 to create carbon monoxide and
oxygen. Nitrous oxide, a powerful greenhouse gas, also
formed to warm the planet enough for liquid water.
“Changing the atmosphere’s chemistry turns out to have made
all the difference for life on Earth,” said Airapetian. But too
much radiation would rip off the atmosphere, so there must
have been a balance between the solar storms and Earth’s
magnetosphere. Additionally, complex molecules like RNA
and DNA may also have formed thanks to energy from those
early solar superflares. AMW Sources: earthsky.org; nasa.gov.
NASA, ESA, STScI/AURA
Dust lanes and star clusters in NGC 1316 hint at a merger with
a spiral 3 billion years ago.
NASA Goddard Space Flight Center
Superflares on the young Sun may have energized the chemical
reactions to seed life on Earth.
Ed Fomalont (NRAO) et al, VLA, NRAO, AUI, NSF
Giant lobes of gas emitting bright radio waves extend from elliptical NGC
1316, a galaxy-eater currently con-suming spiral companion NGC 1317.
7
September 2016
, the Japanese American Citizens League, and the Origami
Therapy Association to bring the annual summer festival to
New York.
JAA’s Suki Terada Ports and Susan Onuma, along with
the Consulate’s Yuki Kaneshige, were instrumental in helping
organize the event. About 80 people, many dressed in tradi-
tional summer yukata dresses and hapi coats, came out to cele-
brate on that warm night. AAA Members generously brought
nine telescopes to the Park, providing excellent viewing of the
stars, the Moon, Jupiter, Venus, and Mars.
The Festival began with remarks from Tomofumi Horiki,
the new Cultural Attaché for the Consulate, who reminisced
about Tanabata Festivals back home in Japan. AAA Board
Member Jason Kendall recited the starry legend of the Festival,
and Manhattan Borough President Gale Brewer stopped by to
say, “Konnichiwa.”
The ancient story behind the Tanabata (which means
“evening of the seventh”) involves a young weaver, the Prin-
Exo-citement The Exoplanet Next Door May Harbor Life
In August, astronomers using the European Southern
Observatory’s 3.6-meter telescope at La Silla in Chile an-
nounced the discovery of an Earth-like exoplanet orbiting
the closest star to Earth, Proxima Centauri. Just 4.2 light-
years away, Proxima b has a mass 1.3 times the Earth’s, and
it’s 11.2-day orbit around Proxima Centauri is in its habitable
zone: liquid water could exist on its surface. Its orbit of
Proxima Centauri is closer than Mercury’s orbit of the Sun,
but its star is a cool, red dwarf, so surface temperatures place
the exoplanet within the star’s “Goldilocks zone.” However,
water may only be found in its sunniest regions, and its syn-
chronous rotation of Proxima Centauri means no seasons.
The surface of Proxima b also experiences intense radiation
from ultraviolet and X-ray flares on its home star. And, with
the exoplanet’s formation history unknown – Did it form
close to its star making it dry and airless? Or did it form fur-
ther out and migrate in? Or was it bombarded by asteroids
with water ice? – then whether it has water or even an atmos-
phere is “pure speculation at this point,” said team leader
Guillem Anglada-Escude. We can assume that its climate is
far different from that on Earth. Proxima b was detected us-
ing the “wobble method,” or radial velocity, looking for
slight, regular movements in a star when it is tugged by an
orbiting object’s gravity. This creates Doppler shifts in the
star’s light spectrum, shifting to blue when it moves toward us
and to red when it moves away. La Silla’s HARPS spectro-
graph has detected hundreds of exoplanets this way. Proxima
b was observed this year with public support from the Pale
Red Dot campaign. “I kept checking the consistency of the
signal every single day during the 60 nights of the Pale Red
Dot...and at 30 days the result was pretty much definitive,”
said Anglada-Escude. Proxima b lies in the Alpha Centauri
star system, which comprises the bright binary stars Alpha
Centauri AB along with Proxima Centauri. Earlier this year,
Stephen Hawking announced Breakthrough Starshot, a project
to develop technology that would launch a fleet of mini light-
propelled spacecraft to the Alpha Centauri system, making the
25-trillion-mile journey in just 20 years. Funded with $100
million dollars from the Russian entrepreneur Yuri Milner,
Starshot now has a new target: “We will definitely aim at
Proxima,” said Breathrough’s Avi Loeb. “ This is like finding
prime real estate in our neighborhood.” AMW
Sources: eso.org; palereddot.org; planetary.org; nytimes.com; space.com.
M. Kornmesser/ESO
Artist’s impression of Proxima b, an Earth-sized exoplanet orbiting the nearest star to us, Proxima Centauri.
8
A Message from the AAA President
Dear AAA Memberss:
The summer is winding down, but early fall weather make for
very pleasant observing. Join us for a trip to the beautiful dark skies of
North-South Lake in the Catskill Mountains on Sep 24-2. Visit http://
www.aaa.org/northsouthlake for more details. For information about
other events and observing sessions visit www.aaa.org/calendar.
This month, AAA’s Fall Astronomy Class begins with
“Astronomy 101: The Basics,” a survey course led by David Kiefer.
Registration is still open, so sign up now at www.aaa.org/education/
classes/.
Meanwhile, AAA’s 2016-2017 Friday night Lecture Series at the
American Museum of Natural History will start up on Sep 30. The
speaker and topic are TBA, so be sure to check back for more details at
www.aaa.org/lectures/.
And don’t forget the upcoming AAA Urban Starfest in Central
Park on October 1. You won’t want to miss this annual event, featur-
ing observing, talks, and prizes – fun for the whole family! Learn
more at www.aaa.org/observing/urban-starfest-in-central-park/. We
hope to see you there!
Marcelo Cabrera, AAA President
September 2016
SEPTEMBER 2016
SUN, Sep 4 Next Oct 2
Solar Observing at Central Park – Manhattan, PTC
@ 1 pm – 3 pm
TUE, Sep 6, 13, 20, 27 Next Oct 4
Observing on the Highline – Manhattan, PTC
@ 7:30 pm – 9:30 pm (Solar Observing begins @ 6 pm on Aug 9)
WED, Sep 7, 14, 21, 28 Next Oct 19, 26
Fall Astronomy Class at Cicatelli Center – Manhattan, M
@ 6:30 pm – 8:30 pm
“Astronomy 101: The Basics” with David Kiefer. This survey covers
celestial events, motions of the Earth and Moon, constellations, the Sun,
seasons, and Zodiac, and planets, stars, nebulae, and galaxies. $60 fee for
AAA Members. Register at www.aaa.org/education/classes/.
FRI, Sep 9
Observing at Carl Schurz Park – Manhattan, PTC
@ 8 pm – 11 pm Next Oct 14
Observing at Floyd Bennett Field – Brooklyn, PTC
@ 8 pm – 11 pm Next Oct 7
Observing at Riverdale – Bronx, PTC
@ 8 pm – 11 pm Next Oct 8
FRI, Sep 10 Next Oct 7
Astro Café at Intrepid Museum – Manhattan, PTC
@ 6:45 pm – 9:30 pm
For Ages 21 and over. Join for a special night of all things Star Trek.
Free to the public, but registration required at www.intrepidmuseum.org.
SUN, Sep 11 Next Oct 9
Solar Observing at Flushing Meadows Park – Queens, PTC
@ 11 am – 1 pm
SAT, Sep 17
Solar Observing at Grand Army Plaza – Brooklyn, PTC
@ 11 am – 1 pm Next Oct 1
Solar Observing on the Hudson at Pier i Cafe – Manhattan, PTC
@ 2 pm – 4 pm
Observing at Los Niño's Park – Bronx, PTC
@ 8 pm – 10 pm Next Oct 15
FRI, Sep 23
Observing at The Evergreens Cemetery – Brooklyn, PTC
@ 6:30 pm – 9:30 pm
Join us for a special observing session at a national historic landmark.
SAT, Sep 24 Next Oct 22
Observing at Great Kills – Staten Island, PTC
@ 8:30 pm – 11 pm
SAT/SUN, Sep 24 & 25 Next Oct 21 & 22
Dark Sky Observing at North-South Lake – Haines Falls MTC
@ 8 pm – 2:30 am
Join AAA for a fieldtrip to observe under the beautiful dark skies of the
Catskill Mountains. Only AAA Members may participate. To reserve a
spot, contact Tom Haeberle at [email protected] .
FRI, Sep 30 Next Oct 19, 26
2016-2017 Lecture Series at AMNH – Manhattan, MP
@ 6:30 pm – 8:30 pm
SAVE THE DATE. Check for details at www.aaa.org/lectures/.
M: Members only; P: Public event; T: Bring telescopes, binoculars; C: Cancelled if cloudy.
For location & cancellation information visit www.aaa.org.
AAA Events on the Horizon
The Amateur Astronomers’ Association of New York Info, Events, and Observing: [email protected] or 212-535-2922
Membership: [email protected] Eyepiece: [email protected]
Visit us online at www.aaa.org.
Other Astronomy Events in and around NYC
MON, Sep 12
@ 7 pm AMNH Special Event (Hayden Planetarium) – Manhattan, X
“Sampling an Asteroid: NASA’s OSIRIS-Rex Mission” with Carter Emmart.
Join for an immersive visualization of the spacecraft at Bennu. (amnh.org)
SAT, Sep 3
@ 8 pm Observe at Rockaway Beach (Boardwalk/Beach 116 St) – Queens, F
“Neptune in Opposition.” NYC Urban Park Rangers guide observing using
binoculars, telescopes, and the naked-eye. (nycgovparks.org)
MON, Sep 19
@ 7:30 pm AMNH Frontiers Lecture (Hayden Planetarium) – Manhattan, X
“Fashion, Faith, and Fantasy in the New Physics of the Universe” with Roger
Penrose. The physicist presents his argument that researchers in string theo-
ry, quantum mechanics, and cosmology may be influenced, and perhaps led
astray, by trends, dogmatic beliefs, or flights of fancy. (amnh.org)
TUES, Sep 20
@ 8 pm Columbia Stargazing/Film Series at Pupin Hall – Manhattan, F
TBA. Observing follows, weather permitting. (outreach.astro.columbia.edu)
F: Free; X: Tickets required (contact vendor for information); T: Bring telescopes, binoculars.
Eyepiece Staff September 2016 Issue
Editor-in-Chief: Amy M. Wagner Copy Review: Richard Brounstein
Contributing Writers: Harriet Brettle, Tony Faddoul, Stan Honda,
Peter Tagatac, Amy Wagner
Eyepiece Logo and Graphic Design:
Rori Baldari
Administrative Support: Joe Delfausse
Printing by McVicker & Higginbotham