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Volume 48, Number 6, Nov–Dec 2011
NNobel Prize forPhysics in 2011
Fifty Yearsof MannedSpaceflight
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A Publication of the Australian Institute of PhysicsPromoting the role of physics in research, education, industry and the community.
EDITORPeter Robertson
ASSISTANT EDITORDr Akin Budi
BOOK REVIEWS EDITORDr John Macfarlane
SAMPLINGS EDITORDr Don Price
EDITORIAL BOARDA/Prof Brian James (Chair)
Dr M. A. Box
Dr J. Holdsworth
A/Prof R. J. Stening
Prof H. A. Bachor
Prof H. Rubinsztein-Dunlop
Prof S. Tingay
ASSOCIATE EDITOR – EDUCATIONDr Colin Taylor [email protected]
ASSOCIATE EDITORSDr John Humble [email protected]
Dr Laurence Campbell [email protected]
Dr Frederick Osman [email protected]
Dr Wen Xin Tang [email protected]
SUBMISSION GUIDELINESArticles for submission to Australian Physics should be sent in electronically.
Word or rich text format are preferred. Images should not be embedded in
the document, but should be sent as high resolution attachments in JPG
format. Authors should also send a short bio and a recent photo. The Editor
reserves the right to edit articles based on space requirements and editorial
content. Contributions should be sent to the Editor.
ADVERTISINGEnquiries should be sent to the Editor.
Published six times a year.
Copyright 2011
Pub. No. PP 224960 / 00008
ISSN 1837-5375
The statements made and the opinions expressed in Australian Physics do
not necessarily reflect the views of the Australian Institute of Physics or its
Council or Committees.
PRODUCTIONControl Publications Pty Ltd
Box 2155 Wattletree Rd PO, VIC 3145.
164 EditorialNobel Prize for Physics
165 President’s ColumnMarc Duldig reports onrecent national andinternational activities ofthe AIP
166 Letters to Editor
169 News & CommentANU astronomer winsNobel PrizeMalcolm McIntosh Prize for2011Barry Inglis Medal and NMIPrizeThe Dish turns fifty
173 A Nobel WeekStephen Luntz interviewsProfessor Brian Schmidt
175 Nobel Prize for Physics in 2011The Royal Swedish Academy of Sciences explains thesignificance of this year’s Nobel Prize for Physics, awarded tothree astronomers who discovered that the rate of expansionof the Universe is accelerating
181 Fifty Years of Manned SpaceflightJonathan Nally provides an overview of the space programsince Yuri Gagarin made a single orbit of the globe in April1961
188 ObituaryTrevor Tansley (1943–2011) by Deb Kane
189 Product NewsA review of new products from Lastek, Warsash Scientific,Coherent Scientific and Agilent Technologies
Inside Back CoverPhysics conferences for 2012
CONTENTS
Volume 48, Number 6, Nov–Dec 2011
NNobel PPrize fforPhysics iin 22011
Fifty YYearsof MMannedSpaceflight
CoverProfessor Brian Schmidt (Australian NationalUniversity) has been awarded the NobelPrize for Physics in 2011. He shares theprize with Professor Adam Riess (JohnsHopkins University) and Professor SaulPerlmutter (University of California, Berkeley)for their discovery that the Universe is ex-panding at an accelerating rate – see pages169, 173 and 175. [credit: Belinda Prattenand the ANU]
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 163
Nobel Prizefor PhysicsIn the 1990s two teams, one led byBrian Schmidt (ANU) and the otherby Saul Perlmutter (U. California),raced each other to find evidencethat the expansion of the Universeis slowing down because of theeffects of gravity. To the astonishmentof both teams, they found exactlythe opposite – the expansion is accelerating, a profound discoverythat has been rewarded with this year’s Nobel Prize for Physics.
While Adam Riess (Johns Hopkins) was a member of the Schmidtgroup, it is well worth noting that two prominent members of thePerlmutter group were the Australian astronomers Brian Boyle(CSIRO) and Warwick Couch (Swinburne University of Technology),so Australia can rightly claim a significant share of the discovery.
Although Australia has won more than its fair share of NobelPrizes in Medicine, it has been a long time between drinks forPhysics. The only other occasion Australia can lay claim to the prizewas the award in 1915 to father and son William and LawrenceBragg for their development of X-ray crystallography.
There are some interesting parallels between the two prizes.William came from England to take up a chair at the University ofAdelaide. He married, raised a family and eventually the familyreturned to England. William and Lawrence carried out the researchthat led to their Nobel Prize on English soil. In contrast, BrianSchmidt was born in the US and moved to the ANU in 1995. Theresearch that led to his Nobel Prize was carried out on Australiansoil.
Congratulations again to Brian!Until the Nobel announcement our cover story was to have been
the article on manned spaceflight by Jonathan Nally on page 181. Ifyou are a regular listener to Robyn Williams’ Science Show, you willbe aware of the excellent segments that Jonathan presents onastronomy and space science. Jon said he does not mind in the leastbeing ‘bumped off’ the front cover by such good news!
At the beginning of this year we set ourselves the goal of gettingthe magazine back on schedule by the end of the year. I’m pleased tonote that we have achieved that goal, but only because of the hardwork of our production team. I would like especially to thank ourAssistant Editor Akin Budi, Guy Nolch at Control Publications,Rod Johnson and Ray Leung at Pinnacle Print Group, Che Giblin atMailPro, and Kim O’Dea at Waldron Smith Management.
On behalf of the production team, we wish you all the best for thecoming Season and look forward to a successful 2012.
PPeter Robertson
164
EDITORIALAustralian Institute of PhysicsAIP website: www.aip.org.au
AIP ExecutivePresident Dr Marc Duldig
Vice President Dr Robert Robinson [email protected]
Secretary Dr Andrew Greentree [email protected]
Treasurer Dr Judith Pollard
Registrar A/Prof Bob Loss
Immediate Past President A/Prof Brian James
Special Projects OfficersDr John Humble
Dr Olivia Samardzic
AIP ACT BranchChair Dr Anna Wilson
Secretary Joe Hope
AIP NSW BranchChair Dr Graeme Melville [email protected]
Secretary Dr Frederick Osman
AIP QLD BranchChair Dr Joel Corney
Secretary Dr Till Weinhold [email protected]
AIP SA BranchChair Dr Scott Foster
Secretary Dr Laurence Campbell [email protected]
AIP TAS BranchChair Dr Elizabeth Chelkowska
Secretary Dr Stephen Newbury [email protected]
AIP VIC BranchChair Dr Andrew Stevenson [email protected]
Secretary Dr Mark Boland [email protected]
AIP WA BranchChair A/Prof Marjan Zadnik [email protected]
Secretary Dr Andrea Biondo [email protected]
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AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 165
Instead of an opinion piece it is timeto bring members up to date withsome of the national and internationalactivities that the Institute has beeninvolved in. Before I do this I mustcongratulate Michelle Simmons onher award as the NSW Scientist ofthe Year.
The AIP is a founding member ofthe Association of Asia Pacific PhysicalSocieties (AAPPS). AAPPS has notbeen a particularly high profile or-ganisation but it is starting to flowerand develop its potential. In thefastest growing region for science andwith a huge population base AAPPSis in the right place to become a sig-nificant force in international physics.AAPPS has been actively pursuingincreased linkage with Europe andthere have been a couple of jointconferences aimed at enhancing col-laborative scientific ventures. AAPPShas also decided that it needs an in-ternal divisional structure. It will beforming discipline and non-disciplinebased divisions starting with areasthat already have some level of inte-gration across the region and wherethe existing bodies might serve asseeds for the new divisions. An ex-ample of a non-discipline division isWomen in Physics, an area that needsstrong support across much of theregion and where some existing or-ganisations can offer a great start.Some of you may already have heardabout one or more of the divisions oreven been invited to play a part. Iencourage you to get involved. Plan-ning is also underway for the AsiaPacific Physics Conference which willbe held in Japan in 2012.
Another international activity wasthe International Union of Pure and
Applied Physics (IUPAP) GeneralAssembly. I attended with two otherAustralian voting delegates, the AIPVice President Rob Robinson andanother AIP member, Bruce McKellar.The most exciting aspect of the meet-ing was the nomination of Bruce asPresident Elect. Bruce was electedunopposed and will serve on the ex-ecutive until he automatically takesup the Presidency at the next GeneralAssembly in three years time. This isthe first time a southern hemispheremember has been elected to the Pres-idency and our congratulations go toBruce.
The IUPAP GA was hosted by theInstitute of Physics (IOP), the or-ganisation from which the AIP grew.I spent some time in discussions withthe IOP looking at strengthening ourbonds. Discussions with the Mem-bership manager were most helpfulas they quickly resolved an issue thathad raised some tension among ourown members. There is an optionfor AIP members to join the IOP atsignificantly reduced rates. Manymembers take up this option butwere dismayed or even offended whentheir membership cards indicatedthey were Affiliate Members, a gradefor people with no qualifications, butan interest in physics. This was alack of communication between ourorganisations. The IOP constitutionrequires all members to go through anomination and vetting process.Therefore AIP members requestingthe discount simply have to completethe membership application form fortheir appropriate grade, include theirCV etc., but note in the cover letterthat they are an AIP Member or Fel-low. This will expedite processing
and on completion they will becomeMembers or Fellows of the IOP andbe able to use the MInstP or FInstPpost nominal. More importantly,independent of their membershipgrade there is no more to pay and fu-ture year fees will continue to be dis-counted in the same way.
Finally, closer to home, FASTShas undergone a rebranding and isnow trading as Science and TechnologyAustralia. STA has been going throughsome challenging times with the gov-ernment reducing the grants thathelped it operate, but it has restructuredits activities and should be able tocontinue to represent scientists to thepoliticians and bureaucrats. It hashad a very effective year with greatlyincreased media presence, playing asignificant part in the removal of theERA journal rankings system, runningthe highly successful Science MeetsParliament and Science Meets Poli-cymakers and will soon host ScienceMeets Superannuation to look at howthe superannuation managers mightinvest a portion of their funds intoscience.
In closing I wish you all the bestfor the festive season. May your hol-idays be safe and refreshing and may2012 be all you could wish for.
MMarc Duldig
PRESIDENT’S COLUMN
National and internationalactivities of the AIP
Dear Editor,
I am grateful to Jeffrey Crosbie for his letter ‘Onabsorbed, equivalent and effective radiation doses’ inAustralian Physics 448(4), 102 (2011), in answer to myplea for information about the current units of nuclearradiation exposure.
I’m happy to confirm that the Gray and the Sievertare now as clear as the rad and the rem were to mewhen I was a junior Health Physicist back in 1959, atthe then-new nuclear power station at Chapelcross inScotland.
At that time, when four 150 MW reactors were op-erating at full power, gamma-ray intensities of about0.6 μSv/hr (microSievert/hour) were measured at thegates to the Chapelcross site. This is some 1000 timesless than the reported level of 0.6 mSv/hr (milliSievert/hr)at the gates of the (damaged) Fukushima reactors.
Sincerely,Dr John C. Macfarlane
Launceston, TAS
Dear Editor,
I am writing in response to the article by Frank Larkinsin the July–August issue of Australian Physics [48(4),105–8 (2011)] on ‘Excellence in Research: Measuringthe Performance of Physics’.
The commentary relates to the statement:‘All the sub-disciplines were rated at or above world
average (≥3) with the exception of AMNPPP (Atomic,Molecular, Nuclear, Particle and Plasma Physics – code0202), a sub-discipline with a very broad classificationcategory of different sub-fields with no insight beingprovided into the relative standings available.’
Perhaps the following observations provide someinsight into this performance. The Australian Bureauof Statistics Field of Research (FoR) codes aggregatethe sub-disciplines below into a single four-digit code(0202):
020201 Atomic and Molecular Physics020202 Nuclear Physics020203 Particle Physics
020204 Plasma Physics; Fusion Plasmas; ElectricalDischarges
020299 Atomic, Molecular, Nuclear, Particle andPlasma Physics not elsewhere classified.
Atomic, Molecular, Nuclear and Plasma Physicshave (by-and-large) similar publication and citationmodalities. However, they are grouped in the 0202category along with Particle Physics, which has strikinglydifferent publication practices.
Particle physicists often publish papers with hundredsof co-authors, and as a result the citation level isextremely high. This has two effects. It increases theinternational benchmark performance for the sub-dis-cipline, and therefore for the 0202 aggregate. Second,it skews the ranking of any group that has one or moremembers collaborating in the publication.
One can try to normalise the result using internationalrelative citation indices, but that doesn’t help becauseparticle physicists are few and far between. The resultis that a Unit of Evaluation (UoE) that includes particlephysicists will boost the ranking of that UoE above theaverage, while those with no particle physicists will fallbelow the average.
The ‘Particle Physics’ effect is evident in the 0202ERA rankings, where Sydney, Melbourne and Adelaidetop the 0202 categories: Each of these departmentshas a significant presence in Particle Physics.
It is also noteworthy that no Australian institutionranks at the highest level (5) in the 0202 category,perhaps because of the absence of a major ParticlePhysics facility in this country. This may also explainwhy the 0202 FoR code is the only Physics code thatranks just below world average.
We have written to the ARC Excellence in Researchcommittees regarding the 0202 code and they are wellaware of the issue. Short of changing the FoR codes(which is done infrequently by the ABS to enableuseful longitudinal comparisons), it will require thesubjective evaluation of 0202 performance data by theERA committees with the above knowledge in mind.
Sincerely,Professor Ken Baldwin
Deputy DirectorResearch School of Physics and Engineering
Australian National UniversityCanberra, ACT
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011166
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ANU astronomer wins Nobel PrizeProfessor Brian Schmidt from the Research School ofAstronomy and Astrophysics at the Australian NationalUniversity has won the 2011 Nobel Prize for Physics.Announced in Stockholm on Tuesday, 4 October, theaward is shared with two US scientists – ProfessorAdam Riess from Johns Hopkins University andProfessor Saul Perlmutter from the University of Cali-fornia, Berkeley. The award is for the discovery thatthe Universe is expanding at an accelerating rate.
Perlmutter will receive one half ofthe 10 million Swedish kroner ($A1.5million) prize, with Schmidt and Riesssharing the other half. It is the first timein almost 100 years that an Australianhas won a Nobel Prize for Physics. In1915 the father and son team Williamand Lawrence Bragg were awarded thePhysics prize for their development ofX-ray crystallography.
Schmidt’s breakthrough was madewhile he led the High-Z SN SearchTeam, which included Riess. Formedby Schmidt in 1994, the research teamexamined distant supernovae to measurethe rate at which the Universe wasmoving apart. Professor Perlmutter re-searched the same field as part of a sep-arate project. Perlmutter’s team includedthe prominent Australian astronomersDr Brian Boyle (CSIRO) and ProfessorWarwick Couch (Swinburne Universityof Technology). In 1998 both teams discovered thatthe Universe is speeding up as it expands, rather thanslowing down as previously thought.
The announcement drew worldwide attention toSchmidt, including a call from the White House. Thenext day he met with the Prime Minister, conductedthirty media interviews and taught a cosmology class.Ms Gillard praised Schmidt and his research team,saying the award would make all Australians proud.“It is another day on which Aussie researchers makeAustralians proud,” said the Prime Minister.
The award has also attracted widespread praise fromthe field of science. Professor Suzanne Cory, presidentof the Australian Academy of Science, said Schmidt’swork had a profound and immediate effect on cosmology.“Previously, it had been thought that the expansion ofthe universe was slowing, or proceeding at a steady
rate. Astrophysicists say the finding that the expansionis in fact accelerating has completely altered our un-derstanding of the Universe and opened up importantnew fields in the study of time and dark energy,” shesaid.
The ANU community is also celebrating Schmidt’saward, the sixth Nobel Prize to be won by an ANU re-searcher since the University’s foundation in 1946.ANU Vice-Chancellor Professor Ian Young said Schmidt’swork had changed the face of astronomy.
“The ANU community is overjoyed to hear thenews that Brian Schmidt has won the Nobel Prize forPhysics,” he said. “His work has helped to unveil aUniverse that, to a large extent, was unknown toscience. He has shown that what we see in the skies isbut a tiny fraction of what is really out there. Brian re-minds us of the infinite mysteries yet to be understood.ANU congratulates a great man and celebrates hismagnificent achievement.”
Born in the US, Schmidt came to the Mt StromloObservatory at the ANU in 1995 after completing hisPhD at Harvard. He is now working on the SkyMappertelescope, a new wide field survey telescope located atthe Siding Spring Observatory, that will conduct themost detailed study ever of the southern sky.
In addition to this week’s Nobel Prize, in 2000Schmidt was awarded the Australian Government’s in-
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 169
NEWS & COMMENT
Stuart Wyithe (left), Brian Schmidt and Bryan Gaensler (University of Sydney)at the PM’s science awards ceremony held at Parliament House in Canberrain October. Wyithe was awarded the 2011 Malcolm McIntosh Prize for PhysicalScientist of the Year, only a few days after Schmidt’s Nobel Prize wasannounced [courtesy: Stuart Wyithe].
augural Malcolm McIntosh award for achievement inthe Physical Sciences, the Pawsey Medal in 2001 bythe Australian Academy of Sciences, the Vainu BappuMedal in 2002 by the Astronomical Society of India,and an Australian Research Council Federation Fel-lowship in 2005.
In 2006 Schmidt was jointly awarded the US$1 millShaw Prize for Astronomy, and in 2007 he shared theUS$0.5 mill Gruber Prize for Cosmology with hisHigh-Z SN Search Team colleagues.
When not star-gazing, Brian Schmidt enjoys a secondcareer as a winemaker and owns a successful vineyardon the outskirts of Canberra.
Barry Inglis Medal and NMI PrizeAt a ceremony held on 5 September at the NationalMeasurement Institute, Lindfield NSW, the Barry InglisMedal for 2011 was awarded to Dr Philip Nakashimaand the NMI Prize to Dr Michael J. Biercuk.
PPhilip Nakashima is a Research Fellow of the MonashCentre for Electron Microscopy, the ARC Centre ofExcellence for Design in Light Metals and the Depart-ment of Materials Engineering at Monash University.His research is focussed on measuring atomic and elec-tronic structure in materials (mainly metals) by electrondiffraction.
Nakashima obtained first class honours in Physicsand Materials Engineering from the University of
Western Australia and, in 2003, received his PhD withdistinction in Physics from the same university. Philip’sresearch interests include electron scattering theory,transmission electron microscopy, quantitative imageprocessing and analysis, accurate structure determinationand metals physics.
The nature of bonding between atoms in metals –the metallic bond – is a vaguely understood phenomenonin materials science. In some metals, such as aluminium,the electrons are so weakly localised that the term ‘freeelectron gas’ is applied. This concept is useful for
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011170
Dr Philip Nakashima.
For his work on the physics of the formation of theUniverse, Professor Stuart Wyithe (University of Mel-bourne) has received the Malcolm McIntosh Prize forPhysical Scientist of the Year.
At the age of 300,000 years after the Big Bang, theUniverse became a cold dark place, with no galaxies,no stars and no light. A billion years later nuclearfusion lit up the Universe as hydrogen atoms clumpedto form stars and galaxies.
Our best telescopes can see the light of the earlygalaxies, but how did the first stars and galaxies form?What triggered the cosmic dawn? What happenedduring the billion-year Dark Age? Wyithe’s theoriesmay lead to some of the answers.
Wyithe grew up in the Blue Mountains where, awayfrom the bright lights of Sydney, the night sky hadmeaning. At secondary school, he was involved in anastronomy club run by a keen teacher. After initially
enrolling in chemical engineering at university, he quitafter two years to go travelling. When he returned, hefinished an honours degree in physics at the Universityof Melbourne and immediately enrolled for a PhD inastrophysics.
After his first year, Stuart took advantage of a visitorprogram to go to Princeton, initially for a semester. Thatwas the last Australia saw of him for several years. Hecompleted his doctorate at Princeton, and then he movedto Harvard University as a NASA Hubble Fellow.
Professor Edwin Turner of the Princeton UniversityObservatory notes: “Stuart and I are co-authors of 15papers of which 11 were submitted during his graduateschool years. It is clear that he is an exceptionallyenergetic and efficient worker. The quality of his workis no less impressive.” Wyithe has now published over100 papers, five of which have appeared in the prestigiousjournal Nature.
Malcolm McIntosh Prize for 2011
loosely explaining certain phenomena such as electrical,thermal and acoustic conductivities, but its usefulnessends there. Over the past eighty years or so, efforts tomeasure the degree and form of metallic bonding inthe best example of a free electron gas – aluminium –have failed partly because the electrons are so weaklylocalised and partly because of physical limitations as-sociated with conventional experiments.
A new approach to electron diffraction has been de-veloped by Nakashima and applied to make the firstunequivocal measurements of metallic bonds in alu-
minium. A number of important physical characteristicsof aluminium, such as mechanical strength and alloyingphenomena, can now be explained directly in terms ofthe accurate picture of metallic bonding gained fromthese measurements. This knowledge provides a newand fundamental basis for understanding the productionof commercial alloys and their industrial processingroutes.
MMichael Biercuk is an experimental physicist at theUniversity of Sydney where he holds a continuingteaching and research appointment. He was educatedin the US, with his undergraduate degree from theUniversity of Pennsylvania, and his Master’s and PhDdegrees from Harvard University.
After conducting postdoctoral research in trappedion quantum information at the National Institute ofStandards and Technology, Biercuk moved to Sydney in2010 to establish the Quantum Control Laboratory.
The ability to detect small forces is at the heart ofmany modern technologies including advanced spin-resonance and microscopy techniques. The detectorsproviding this capability are mostly based on tiny, vi-brating mechanical beams which respond to very slightdisturbances from external forces. As nanofabricationtechniques have improved and device dimensions haveshrunk, we have seen improved performance fromthese mechanical oscillators. In a new developmentBiercuk’s group employs atomic ions trapped using
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 171
Dr Michael Biercuk.
Wyithe’s recent work has focused on the evolutionof the structure of the Universe. He notes: “Astronomyis all about trying to understand how the Universecame to look the way it does, as well as how it works.What’s not understood is how the galaxies themselvesformed. This is inexorably linked with the transitionfrom a Universe of cold, uncharged, atomic hydrogento being ionised and hot. This ‘Epoch of Reionisation’is the last non-understood event in the history of theUniverse.”
“The obvious candidate for the energy that drovethis process is the formation of stars, and that is wheremost attention has been focused.” Another possiblesource is the formation of supermassive black holes.And it is in these two possibilities that Wyithe has beenmost interested.
“The reason that Stuart’s work has had so much im-pact”, says Professor Matthew Colless, Director of the
Australian Astronomical Observatory, “is that not onlydoes it elucidate a fundamentally important epoch incosmic evolution, but it has also focused on making ex-plicit, detailed and testable predictions for the large-scale structures that should be observed. These predictionsstrongly suggest that there are rich observationalsignatures of the Epoch of Reionisation just beyondthe limit of current facilities.”
Wyithe now chairs the science committee for theMurchison Widefield Array, a revolutionary new telescopebeing constructed by a US–Australia–India consortiumin Western Australia. It will test some of the ideas to beincorporated into the Square Kilometre Array.
Wyithe was once considered to be Australia’s toprock climber though, with a young family, he hascutback on this activity. He was recently awarded anARC Australian Laureate Fellowship [see AP 48(5),135].
electromagnetic fields as ultra-sensitive mechanical os-cillators approaching the ultimate scaling limits ofsensor technology.
Through the development of new measurementtechniques for trapped ions, the Quantum ControlLaboratory has demonstrated systematic force-detectionsensitivity over 1000 times better than previous ap-proaches. The results realised force detection sensitivityin the yoctonewton regime – where yocto (=10-24) isthe smallest defined SI prefix.
Biercuk’s research has also addressed the speed withwhich a measurement can be performed and mayspark interest in a new generation of atom-basedsensing devices with applications in research and themining and defence industries.
The Dish Turns FiftyThe Dish – CSIRO’s 64-m radio telescope at Parkes inNSW – threw open its doors to the public on theweekend of 8 & 9 October. The Open Days featuredfree telescope tours, talks, exhibits and children’sactivities. Dr Megan Clark, CSIRO chief executive,and Dr Phil Diamond, chief of CSIRO Astronomyand Space Science (CASS), spoke at a ceremony tocommemorate the telescope’s 50th anniversary.
The telescope, located 20 km north of the Parkestownship, was inaugurated on 31 October 1961. Thetelescope is probably best known for its role in receivingthe television signals of the Apollo 11 Moon landingin July 1969, as popularised in the film ‘The Dish’ firstscreened in October 2000.
“Parkes is still one of the best-performing radio tel-escopes in the world”, said Phil Diamond, who was re-cently appointed chief of CASS after being director ofthe famous Jodrell Bank dish near Manchester.
The telescope played a crucial role in the discoveryof quasars and in determining their nature. The Dishhas discovered over one-half of the 2000 known pulsars,more than all of the world’s radio telescopes puttogether. Recently it discovered the first binary pulsarsystem, which is expected to lead to the most stringenttests of General Relativity.
Repeated upgrades have made the telescope 10,000times more sensitive than when it was opened on a
blustery day in 1961. Its surface panels, focus cabin,receiving equipment, pointing system, control paneland data processors have all been replaced – in mostcases more than once. “The telescope is like a councilworker’s broom – it’s had three new handles and twonew brushes, but it’s still the same broom”, Dr Diamondsaid.
“The standout new technology has been the multibeam– that is, multipixel – receiver that allows the telescopeto see more of the sky at once”, he said. “This has beenthe mainstay of much of what Parkes has achieved inrecent years.”
Planning for the telescope began in 1954, and builton Australia’s world leadership in the new field ofradio astronomy. Half the funding came from the USCarnegie and Rockefeller foundations and the otherhalf from the Australian government. It was designedby the British firm of Freeman Fox (which earlier haddesigned the Sydney Harbour Bridge). It was constructedby the German firm MAN.
NASA used the Parkes dish as its model in designingand building its series of dishes that form the DeepSpace Network, one of which is located at Tidbinbillanear Canberra.
“Three generations of scientists have explored theUniverse with Parkes”, said Phil Diamond. “The Dishis an icon of Australian science.”
The celebrations at Parkes concluded with a sympo-sium held during the first week of November.
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011172
Iconic image – the Parkes dish shortly before itsinauguration on 31 October 1961. On horseback is AustieHelm who sold part of his farm to CSIRO to provide a site forthe telescope. [courtesy: National Library of Australia]
Prof Brian Schmidt has lost count of the numberof interviews he conducted in the week after theannouncement that he had won the 2011 Nobel
Prize for Physics. The media office at the Australian Na-tional University, where Schmidt is professor of astronomy,estimates it at 150. At least 16,000 articles were publishedworldwide during that time. In addition Schmidtsuddenly found himself invited to meet the PrimeMinister and give public lectures.
While Schmidt is full of praise for the ANU mediaoffice, which took over his diary soon after the prize wasannounced, they have not been able to lighten histeaching load, which he describes as the largest obstacleto meeting the sudden rush of requests. He is, he says,“still waiting for an opportunity to think”.
Schmidt did manage to squeeze an interview withAustralasian Science into his agenda, albeit after the in-tensity of the first rush had passed. We benefited fromSchmidt’s positive memories of an article he wrote forour themed issue on astronomy (AS, Jan/Feb 2009,pp.12–14), which has suddenly become an auspiciousedition; Schmidt’s opening feature was followed by anarticle by Stuart Wyithe (AS, Jan/Feb 2009, pp.15–18), who won the 2011 Malcolm McIntosh Prize forPhysical Scientist of the Year a few days after Schmidt’sNobel Prize was announced.
As many of the 16,000 articles have noted, the NobelPrize came as a surprise to Schmidt, although he says hehad a fair idea when a call from a woman with aSwedish accent asked him to stand by for a very importantphone call.
The Nobel Prize was awarded for Schmidt’s role inthe discovery that the expansion of the Universe is ac-
celerating. Since gravity inevitably acts to pull theUniverse’s matter together, it had been assumed that theparting of galaxies must be happening at a decreasingrate. The crucial question was considered to be whethergravity would prove strong enough to eventually reversethis expansion, causing everything to collapse again.
Schmidt, along with Prof. Adam Reiss of JohnsHopkins University, measured the brightness of Type 1asupernovae, which all produce similar amounts of light.With the intrinsic and observed brightness known it ispossible to calculate the stars’ distances. The rate ofmovement away from us was found using the establishedtechnique of measuring the red shift of emission lines inthe object’s spectra.
Putting the idea into practice, however, required thediscovery of a substantial number of 1a supernovae,which had only been observed rarely. However, Schmidtand Reiss realised that advances in telescope andinstrument design made this possible.
“During the course of a night these telescopes cansurvey more than a million galaxies and find tens of su-pernovae,” Schmidt wrote in Australasian Science. “Since1994 astronomers have found more than 500 explodingstars scattered from the present to 11 billion years ago.”
To their astonishment Schmidt and his colleaguesfound “that the Universe has been speeding up for thepast six billion years rather than slowing down”. Thepublication of this finding in 1998 led to the revival ofEinstein’s briefly proposed idea of a form of mattercalled dark energy that repels itself, balancing gravity.Further examination of the data led to the conclusionthat the Universe is actually 75% dark energy, with theother 25% made up of a combination of the matter we
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A Nobel WeekStephen Luntz
Brian Schmidt’s world was turned upside-down when he was awarded the 2011Nobel Prize for Physics for research that has turned our understanding of theUniverse inside out.
can actually see and the more traditional dark matter.The Nobel’s science prizes cannot be shared between
more than three people, so the other winner of the 2011Physics Prize is Prof Saul Perlmutter of the LawrenceBerkeley National Laboratory, who led a competingteam conducting a similar supernovae search, with eachteam publishing within a few weeks of the other.
Schmidt is keen for everyone to be aware that the dis-coveries were very much a team achievement. “Therewere 18 other people on the team,” he says. “You don’thave to name them all, but I want to get out the ideathey were important.”
Schmidt, Reiss and Perlmutter shared the Shaw Prizefor Astronomy in 2006 and the Gruber CosmologyPrize in 2007. Nevertheless, prizes other than the Nobelsdo not make scientists famous. For a day after the an-nouncement, typing “Brian Schmidt” into Wikipediaproduced the page of a composer of music for pinballand video games, with a link at the top to the apparentlyless interesting astrophysicist. This has since been re-versed.
Some Nobel Prize winners have been woken by thephone call, and had to confront the media still half-awake. Schmidt had more luck, being called at 8:30 pmand given 10 minutes to make a comment on theofficial announcement. “The first call came from ABCLateline, who asked if they could come out and visitme,” Schmidt recalls. In fact, a film crew was already onits way, despite having only a vague idea of whereSchmidt lives.
Meanwhile the phone did not stop ringing. EventuallySchmidt called the ANU media office and asked ifsomeone could take over screening his calls. Schmidtadds: “They’d been calling to offer but couldn’t getthrough”.
Schmidt was up until 1:30 am answering calls beforegoing to bed. His father, a fisheries biologist in Anchorage,Alaska, where Schmidt went to high school, called at2:30 am. “I didn’t take the call but it woke me up,”Schmidt says. By the time he started his first morninginterviews at 6:45 am he’d had 2 hours sleep.
Schmidt also received a supportive call from Prof.Barry Marshall, winner of the 2005 Nobel Prize forMedicine, who “gave me his sense of things”. Nevertheless,he certainly felt under pressure. “You’re only one sentenceaway from disaster with the media the way it is.”
In the course of the following days Schmidt met notonly the Prime Minister and Science Minister but alsothe Finance Minister. Ten days after the announcement
he flew to Hawaii for a meeting of the committee thatoversees the Gemini Telescopes, on which he serves.Two public talks were added to the schedule, so it was “amore intense trip than usual”.
For some winners the Nobel Prize is a door to researchopportunities for which they could never previously getfunding, but that is not the case for Schmidt. “I’m inthe middle of a huge project for the next 5–7 years. Idon’t need anything more. For that period I just want tofocus on Skymapper, making a map of the entiresouthern sky, identifying locations for the really interestingthings we want to come back and study in detail withGemini South and the Anglo-Australian Telescope.”
On the other hand the status of the Prize, and thefact that millions of people now know his name, givesSchmidt a platform. “I think I have a responsibility totry to ensure that Australia and the world understandhow science works and why it is important,” Schmidtsays. “I don’t want to mix science and policy, but I havebeen pushing for the Academy of Science to articulatescientific positions on issues of relevance. In the US thisis a formalised role for the academies, and I’d love to seethat here.”
Schmidt was asked to speak at the awarding of thePrime Minister’s Science Prizes, where he sat next toPrime Minister Julia Gillard. “I tried to remind peoplethat Australia has gone from being far away from therest of the developed world to being on the edge of areaswhere development is happening. We should be raisingexpectations of ourselves,” Schmidt says.
“I hope we raise our education expectations commen-surate with our wealth so that science can be the engineof prosperity when the commodity boom is over. I wantto make people aware of how important science is; howuniversities and CSIRO make the world a better place.”
His message to those assembled for the PM’s Prizescould not have been missed by Gillard or her advisers.“I often hear it said that science and education policynever won an election. But nations rise and fall on theoutcomes of science and education.
“The lack of political acknowledgement of this maybe because science and education do not run on a 3-year cycle. It takes decades for such policies to runtheir course, but they provide a similarly long legacy –12 years of good education provides a 50-year legacy.”
Stephen Luntz is a writer for Australasian Science magazine (seep.167). This interview first appeared in the December 2011 issue. Iam most grateful to the editor of Australasian Science, Guy Nolch, forpermission to reproduce the interview here – Ed.
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Written in the StarsThe Royal Swedish Academy of Sciences
‘Some say the world will end in fire; Some say in ice…’Robert Frost, Fire and Ice, 1920
What is the fate of the Universe? Probably it will end in ice if we are to believe thisyear’s Nobel Laureates. They have carefully studied several dozen exploding stars,called supernovae, in faraway galaxies and have concluded that the expansion ofthe Universe is speeding up.
NOBEL PRIZE FOR PHYSICS 2011
The expansion of the Universebegan with the Big Bang 14 billionyears ago, but slowed down duringthe first several billion years.Eventually it started to accelerate.The acceleration is believed to bedriven by dark energy, which in thebegin ning constituted only a smallpart of the Universe. But as matterbecame diluted by the expansion,the dark energy became moredominant.
The discovery came as a complete surprise even to theNobel Laureates themselves. What they saw would belike throwing a ball up in the air, and instead of havingit come back down, watching as it disappears moreand more rapidly into the sky, as if gravity could notmanage to reverse the ball’s trajectory. Something sim-i lar seemed to be happening across the entire Universe.
The growing rate of the expansion implies that theUniverse is being pushed apart by an unknown formof energy embedded in the fabric of space. This darkenergy makes up a large part of the Universe, morethan 70%, and it is an enigma, perhaps the greatest inphysics today. No wonder then that cosmology wasshaken at its foundations when two different researchgroups presented similar results in 1998.
Saul Perlmutter headed one of the two researchteams, the Supernova Cosmology Project, initiated adecade earlier in 1988. Brian Schmidt headed anotherteam of scientists, which towards the end of 1994launched a competing project, the High-Z SupernovaSearch Team, in which Adam Riess was to play acrucial role.
The two research teams raced each other to map theUniverse by finding the most distant supernovae. Byestablishing the distance to the supernovae and thespeed at which they are moving away from us, the twogroups hoped to reveal our cosmic fate. They expectedto find signs that the expansion of the Universe wasslowing down, which would lead to equilibrium betweenfire and ice. What they found was the opposite – theexpansion was accelerating.
Cosmos is growingIt is not the first time that an astronomical discoveryhas revolutionised our ideas about the Universe. Onlya hundred years ago, the Universe was considered tobe a calm and peaceful place, no larger than our owngalaxy, the Milky Way. The cosmological clock wasticking reliably and steadily and the Universe was eter -nal. Soon, however, a radical shift would change thispicture.
At the beginning of the 20th century the Americanastronomer Henrietta Leavitt found a way of measuringdistances to faraway stars. At the time, women as-tronomers were denied access to the large telescopes,but they were frequently employed for the cumbersometask of analysing photographic plates. Leavitt studiedthousands of pulsating stars, called Cepheids, andfound that the brighter ones had longer pulses. Usingthis information, Leavitt could calculate the intrinsicbrightness of Cepheids. If the distance of just one ofthe Cepheid stars is known, the distances to otherCepheids can be established – the dimmer its light, thefarther away the star. A reliable standard candle wasborn, a first mark on the cosmic yardstick that is stillused today.
By making use of Cepheids, astronomers wouldsoon conclude that the Milky Way is just one of manygalaxies in the Universe. In the 1920s Edwin Hubble,using the world’s largest telescope on Mount Wilsonin California, studied the so-called redshift that occurswhen a source of light is receding from us. Theconclusion was that the galaxies are rushing away fromus and each other, and the farther away they are, thefaster they move – this is known as Hubble’s law.
The coming and going of the cosmologicalconstantWhat was observed in space had already been suggestedby theoretical calculations. In 1915 Albert Einsteinpublished his General Theory of Relativity, which hasbeen the foundation of our understanding of the Uni -verse ever since. The theory describes a Universe thathas to either shrink or expand.
This disturbing conclusion was reached about adecade before the discovery of the ever-fleeing galaxies.Not even Einstein could reconcile the fact that theUniverse was not static. So in order to stop thisunwanted cosmic expansion, Einstein added a constantto his equations that he called the cosmological constant.Later, Einstein would consider the insertion of thecosmological constant his biggest mistake. However,with the obser vations made in 1997–98 that areawarded this year’s Nobel Prize, we can conclude thatEinstein’s cosmo logical constant – put in for the wrongreasons – was actually brilliant.
The discovery of the expanding Universe was aground-breaking first step towards the now standardview that the Universe was created in the Big Bangalmost 14 billion years ago. Both time and space began
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“The two research teamsraced each other to mapthe Universe by finding themost distant supernovae.”
then. Ever since, the Universe has been expanding;galaxies are moving away from each other due to thecosmological expansion. But where are we heading?
Supernovae – the new measure of theUniverseWhen Einstein got rid of the cosmological constantand surrendered to the idea of a non-static Universe,he related the geometrical shape of the Universe to itsfate. Is it open or closed, or is it something in between– a flat Universe? An open Universe is one where thegravitational force of matter is not large enough toprevent the expansion of the Universe.
All matter is then diluted in an ever larger, evercolder and ever more empty space. In a closed Universe,
on the other hand, the gravitational force is strongenough to halt and even reverse the expansion. So theUniverse eventually would stop expanding and fallback together in a hot and violent ending, a BigCrunch. Most cosmologists, however, would prefer tolive in the most simple and mathematically elegantUniverse: a flat one, where the expansion is believed todecline. The Universe would thus end neither in firenor in ice. But there is no choice. If there is acosmological constant, the expansion will continue toaccelerate, even if the Universe is flat.
This year’s Nobel Laureates expected to measure thecosmic deceleration, or how the expansion of the Uni -verse is slowing. Their method was in principle thesame as the one used by astronomers more than six
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A white dwarfdraws gas fromits neighbourand when it hasgrown to 1.4solar masses, itexplodes as atype Iasupernova.
decades earlier: to locate distant stars and to measurehow they move. However, that is easier said than done.Since Henrietta Leavitt’s days many other Cepheidshave been found that are even farther away. But at thedistances that astronomers need to see, billions oflight-years away, Cepheids are no longer visible. Thecosmic yardstick needed to be extended.
Supernovae became the new standard candles [Ed:see Fig. 2 in the article by Chris Blake in AP 448(5),149–53 (2011)]. More sophisticated telescopes on theground and in space, as well as more powerful computers,opened the possibility in the 1990s to add more pieces
to the cosmological puzzle. Crucial were the light-sensitive digital imaging sensors – charged-coupleddevices or CCD – the invention by Willard Boyle andGeorge Smith who were awarded Nobel Prize forPhysics in 2009.
White dwarfs explodingThe newest tool in the astronomer’s toolbox is a specialkind of star explosion, the type Ia supernova. During afew weeks, a single such supernova can emit as muchlight as an entire galaxy. This type of supernova is theexplosion of an extremely compact old star that is asheavy as the Sun but as small as the Earth – a whitedwarf. The explosion is the final step in the whitedwarf ’s life cycle.
White dwarfs form when a star has no more energyat its core, as all hydrogen and helium have beenburned in nuclear reactions. Only carbon and oxygenremain. In the same way, far off in the future, our Sunwill fade and cool down as it reaches its end as a whitedwarf.
A far more exciting end awaits a white dwarf that ispart of a binary star system, which is fairly common.In this case, the white dwarf ’s strong gravity robs thecompanion star of its gas. However, when the whitedwarf has grown to 1.4 solar masses, it no longermanages to hold together. When this happens, theinterior of the dwarf becomes sufficiently hot forrunaway fusion reactions to start, and the star getsripped apart in seconds.
The nuclear fusion products emit strong radiationthat increases rapidly during the first weeks after theexplosion, only to decrease over the following months.So there is a rush to find supernovae – their violent ex-plosions are brief. Across the visible Universe, aboutten type Ia supernovae occur every minute. But theUniverse is huge. In a typical galaxy only one or twosupernova explosions occur in a thousand years. InSeptember 2011, we were lucky to observe one suchsupernova in a galaxy close to the Big Dipper, visiblejust through a pair of regular binoculars. But most su-pernovae are much farther away and thus dimmer. Sowhere and when would you look in the canopy of thesky?
An astounding conclusionThe two competing teams knew they had to comb theheavens for distant supernovae. The trick was to com -pare two images of the same small piece of the sky,
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Supernova 1995ar. Two images of the same area of skytaken three weeks apart. In the second image, the small dotof light was discovered and its status as a type Ia supernovawas established after further observations of its light curve.The light curve is the same for all type Ia supernovae andmost light is emitted during the first few weeks.
corresponding to a thumbnail at arm’s length. The firstimage has to be taken just after the new moon and thesecond three weeks later, before the moonlight swampsout starlight. Then the two images can be compared inthe hope of discovering a small dot of light – a pixelamong others in the CCD image – that could be asign of a supernova in a galaxy far away. Only supernovaefarther than a third of the way across the visibleUniverse were used, in order to eliminate local distor-tions.
The researchers had many other problems to dealwith. Type Ia supernovae are not quite as reliable asthey ini tially appeared – the brightest explosions fademore slowly. Furthermore, the light of the supernovaeneeded to be extracted from the background light oftheir host galaxies. Another important task was toobtain the correct brightness. The intergalactic dustbetween us and the stars changes starlight. This affectsthe results when calculating the maximum brightnessof supernovae.
Chasing supernovae challenged not only the limitsof science and technology but also those of logistics.First, the right kind of supernova had to be found.Second, its redshift and brightness had to be measured.The light curve had to be analysed over time in order
to be able to compare it to other supernovae of thesame type at known distances. This required a networkof scientists that could decide quickly whether aparticular star was a worthy candidate for observation.They needed to be able to switch between telescopesand have observation time at a telescope grantedwithout delay, a procedure that usually takes months.They needed to act fast because a supernova fadesquickly. At times, the two competing research teamsdiscreetly crossed each other’s paths.
The potential pitfalls had been numerous, and thescientists actually were reassured by the fact that theyhad reached the same amazing results: all in all, theyfound some 50 distant supernovae whose light seemedweaker than expected. This was contrary to what theyhad envisioned. If cosmic expansion had been losingspeed, the supernovae should appear brighter. However,the supernovae were fading as they were carried fasterand faster away, embedded in their galaxies. Thesurprising conclusion was that the expansion of theUniverse is not slowing down – quite to the contrary,it is accelerating.
From here to eternitySo what is it that is speeding up the Universe? It iscalled dark energy and is a challenge for physics, ariddle that no one has managed to solve yet. Severalideas have been proposed. The simplest is to reintroduceEin stein’s cosmological constant, which he once rejected.At that time, he inserted the cosmological constant asan anti-gravitational force to counter the gravitationalforce of matter and thus create a static Universe. Today,the cosmological constant instead appears to make theexpansion of the Universe to accelerate.
The cosmological constant is, of course, constant,and as such does not change over time. So dark energybecomes dominant when matter, and thus its gravity,gets diluted due to expansion of the Universe overbillions of years. According to scientists, that wouldaccount for why the cosmological constant entered thescene so late in the history of the Universe, only five to
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The accelerating expansion of the Universe was proclaimed‘Breakthrough of the Year’ in the December 1998 issue ofthe journal Science [volume 282, number 597]. On the cover,Albert Einstein gazed upon his cosmological con stant,which has returned to the forefront of cosmology [credit:John Kascht and Science].
“During a few weeks, asingle supernova can emitas much light as an entiregalaxy.”
six billion years ago. At about that time, the gravitationalforce of matter had weakened enough in relation tothe cosmological constant. Until then, the expansionof the Universe had been decelerating.
The cosmological constant could have its source inthe vacuum, empty space that, according to quantumphysics, is never completely empty. Instead, the vacuumis a bubbling quantum soup where vir tual particles of
matter and antimatter pop in and out of existence andgive rise to energy. However, the simplest estimationfor the amount of dark energy does not correspond atall to the amount that has been measured in space,which is about 10120 times larger. This constitutes a gi-gantic and still unex plained gap between theory andobservation – on all the beaches of the world there areno more than 1020 grains of sand.
It may be that the dark energy is not constant afterall. Perhaps it changes over time. Perhaps an unknownforce field only occasionally generates dark energy. Inphysics there are many such force fields that collectivelygo by the name quintessence, after the Greek name for
the fifth element. Quintessence could speed up theUniverse, but only sometimes. That would make itimpossible to foresee the fate of the Universe.
Whatever dark energy is, it seems to be here to stay.It fits very well in the cosmological puzzle that physicistsand astronomers have been working on for a longtime. Accord ing to current consensus, about threequarters of the Uni verse consist of dark energy. Therest is matter. But the regular matter, the stuff thatgalaxies, stars, humans and flowers are made of, is only5% of the Universe. The remaining matter is calleddark matter and is so far hidden from us.
The dark matter is yet another mystery in our largelyunknown cosmos. Like dark energy, dark matter is in-visible. So we know both only by their effects – one ispushing, the other one is pulling. They only have theadjective ‘dark’ in common.
Therefore the findings of the 2011 Nobel Laureatesin Phys ics have helped to unveil a Universe that is95% unknown to science. And everything is possibleagain.
CreditsThis is a modified and shortened version of an articlefor a popular general audience prepared by the RoyalSwedish Academy of Sciences: Science Editors: LarsBergström, Olga Botner, Lars Brink, Börje Johansson,The Nobel Committee for Physics. Illustrations, unlessotherwise indicated: ©Johan Jarnestad/Royal SwedishAcademy of Sciences. Editor: Annika Moberg. ©RoyalSwedish Academy of Sciences. See www.nobelprize.orgnobel_prizes/physics/laureates/2011/index.html.
Additional information on this year’s Prize, includinga 19-page scientific background article in English, maybe found at the website of the Royal Swedish Academyof Sciences, kva.se, and at nobelprize.org. The latteralso includes web-TV versions of the press conferencesat which the awards were announced.
ReferencesA. Riess, et al., ‘Observational evidence from supernovae
for an accelerating Universe and a cosmological constant’,Astron. J. 1116, 1009–38 (1998).
S. Perlmutter, et al., ‘Measurement of Ω and Λ from 42high-redshift supernovae’, Astrophys. J. 517, 565–86(1999).
S. Perlmutter and B. P. Schmidt, ‘Measuring cosmologywith supernovae’, Lecture Notes in Physics (2003);arxiv.org/abs/astro-ph/03034289.
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The implication of the discovery is that three quarters of theUniverse is an unknown form of dark energy. Together withequally unknown dark matter, the dark energy constitutes95% of the Universe.
“… the findings of the 2011Nobel Laureates in Phys icshave helped to unveil aUniverse that is 95%unknown to science.”
“Let’s go!” With those words, spokenby Yuri Gagarin at T-0 on 12 April 1961,the world changed forever. As theSoviet cosmonaut thundered skywardaboard the Vostok 1 spacecraft, a newera in exploration had dawned. For thefirst time, humankind had left the safeand comforting bosom of mother Earthand ventured into the unknownblackness of space.
Gagarin’s single orbit stunned and enthralledthe world. It was true – a human couldsurvive and operate beyond the atmosphere.
For billions of years, all life on Earth had been confinedto a shallow habitat that spanned from just below theplanet’s surface to some way up into its atmosphere.But no longer. Twentieth-century technology had ex-plosively boosted our species’ range to new heights.
So you’d think that, 50 years later, the exploitationof this new frontier would be in full swing. But it isn’t.It’s still in its infancy. Although a lot has been achieved,there is still a long way to go – but the roadmap is be-coming perhaps somewhat easier to read.
The race beginsGagarin’s flight, followed less than a week later by theabortive Bay of Pigs invasion of Cuba, put the USAfirmly on the back foot. At this point, with the ColdWar in full swing, John F. Kennedy had been presidentfor less than three months and the Soviet’s repeatedsuccesses were taking their toll on American moraleand prestige. Kennedy decided the USA had to respond
with something big, something daring… somethingthey had a chance of winning.
Calling in his advisers, he asked what could be doneto beat the Soviets. What about space? That was thenew frontier. What could be done there? What aboutall this talk of space stations or flying to the Moon?Could we do that? Rapid consultations with a handfulof engineers in the nascent NASA (the agency that hadbeen formed less than three years earlier) came up withthe answer – a manned mission to the Moon and backwas technically feasible within about 10 years, althoughthe technologies and techniques did not then exist.
And so it was that on 25 May 1961, Kennedy an-nounced plans for a lunar mission: “I believe that thisnation should commit itself to achieving the goal,before this decade is out, of landing a man on theMoon and returning him safely to the Earth. No singlespace project in this period will be more impressive tomankind, or more important in the long-range explo-ration of space; and none will be so difficult or expensiveto accomplish.”
It’s worth remembering that by this point, the USA
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50 Years of Manned SpaceflightA Brief HistoryJonathan Nally
Soviet cosmonaut Yuri Gagarin was the first person to reachouter space, during the flight of Vostok 1 on 12 April 1961.
had made only one manned spaceflight – Alan Shepard’s15-minute sub-orbital lob. America had committeditself to a lunar landing before it had even put a personinto orbit. It was a high-risk gamble upon which thenation was embarking.
The first 20 yearsThe rest, as they say, is history. The Apollo programmewas a tremendous success, landing 12 men on thelunar surface and returning them safely to Earth. Eventhe failed Apollo 13 mission was considered a daringand triumphal accomplishment.
The Soviets, having realised they wouldn’t win theMoon race, turned their attention to low-Earth orbit(LEO) operations, launching many crews into spaceand, in the early 1970s, the world’s first space stations(the Salyut series). Their achievements were perhapsunspectacular but, like the hare and the tortoise, theyplodded along and made continual progress.
The USA, with tough economic challenges, domestic
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Astronaut James B. Irwin, lunar modulepilot, works at the Lunar Roving Vehicleduring the first Apollo 15 lunar surface
extravehicular activity (EVA-1) at theHadley–Apennine landing site. The
shadow of the lunar module ‘Falcon’ is inthe foreground. This view is looking
north–east, with Mount Hadley in thebackground. The photograph was taken
by astronaut Commander David R. Scott.[credit: NASA]
“Kennedy decided the USAhad to respond withsomething big, somethingdaring… something theyhad a chance of winning.”
social upheaval and an intractable war in Vietnam,quickly tired of the space adventure. Facing potentialoblivion at the beginning of the 1970s, NASA pushedfor a new beginning in space, one that promised toreduce the cost but boost the returns – a reusable spaceshuttle, followed by a permanently manned spacestation. The space shuttle programme was approved byonly the skin of its teeth, and only after the US AirForce decided to support it (but not with dollars). De-velopment began immediately, with first flight plannedfor the late 1970s.
Meanwhile, using surplus Apollo hardware, the USlaunched Skylab, a very large space station aboardwhich crews would conduct scientific experiments in arange of disciplines. Three crews of three men visitedthe station in the early 1970s, gaining for NASAvaluable insights into the challenges of conductinglong-duration space missions. This was followed inJuly 1975 by the joint Soviet–US Apollo–Soyuz TestProject, a symbolic effort at détente in LEO. The twoSoviet and US spacecraft docked in orbit and the
crews spent an enjoyable few days conducting experimentsand generally having a good time.
It was hoped that the space shuttle would be flyingin time to deliver a rocket module to the mothballedSkylab, boosting it to a higher orbit for possible futureuse. But the shuttle became delayed, and Skylab’s orbiteventually decayed and led to re-entry in 1979, withpieces of it falling over Western Australia. The firstshuttle launch came on 12 April 1981, twenty years tothe day since Gagarin’s historic flight.
ConsolidationThe 1980s saw the Soviets continue investigations intolong-duration spaceflight aboard their space stations,including Mir. Cosmonauts set longer and longerrecords for stays in space, and scientists learned a lotabout the long-term effects of the microgravity envi-ronment on the human body.
For the USA, it was a new and exciting era as thespace shuttle began flying, carting satellites and exper-iments into orbit. At first it seemed like the promise of
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Space shuttle Atlantis (STS-135) is rolled over to the Orbiter Processing Facility shortly after landing at NASA’s Kennedy SpaceCenter Shuttle Landing Facility, completing its 13-day mission to the International Space Station and the final flight of NASA’sSpace Shuttle Program on 21 July 21 2011, in Cape Canaveral, Florida. Overall, Atlantis spent 307 days in space and travellednearly 126 million miles during its 33 flights. Atlantis, the fourth orbiter built, was launched on its first mission on 3 October1985. [credit: NASA/Bill Ingalls]
science fiction was coming true – regular flights usinga spacecraft that could be turned around and flownagain within a short span of time. But it soon becameapparent that the original ambitions for frequent turn-arounds were not being met, and costs were climbing.
Then in 1986 came the terrible tragedy of Challenger,a disaster all the more distressing for being foreseeableand preventable. The problem with the rubber seals inthe joints between booster rocket segments had longbeen known, and the decision to launch on a day offreezing temperatures (when the rubber would bebrittle) doomed the seven astronauts, destroyed a bil-lion-dollar machine and set the US manned spaceflightprogramme back years.
Several policy changes were implemented, includingthe decision to no longer carry commercial satellitepayloads (commercial pressure to launch was one ofthe factors cited in the Challenger case), and to notcarry payloads that used a particular kind of boosterrocket (now deemed too dangerous). The US militaryalso gave up on the shuttle, and the launch tower ithad built (but never used) in California was moth-balled.
The International Space StationBy the end of the 1980s, the superpower geopoliticalsituation had changed dramatically. The Soviet Unionwas collapsing, and the USA and Russia were exploringways in which they could co-operate peacefully. Oneof the arenas chosen was spaceflight. For some time,the USA had been in the process of planning for amajor space station that would have internationalinput. With Russia now America’s new best friend,NASA was directed to include them in their planning.
The result is the International Space Station (ISS), ahugely ambitious – and hugely expensive – multi-national effort built around US and Russia cores. Con-
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The space shuttle Atlantis is seen over the Bahamas prior to a perfect docking with the International Space Station. Part ofa Russian Progress spacecraft which is docked to the station is in the foreground. Atlantis was to make the final flight in thespace shuttle programme. [credit: NASA]
“The first shuttle launchcame on 12 April 1981,twenty years to the daysince Gagarin’s historicflight.”
struction commenced in 1998 and is almost complete– the final major component will be the Russian Mul-tipurpose Laboratory Module, scheduled for launch in2012. Over 100 metres long, 417 tonnes in mass andaround 1000 cubic metres in volume, the ISS is trulyhuge. It has 15 pressurised modules powered by 16huge solar power arrays. Its crew of six is drawn frommember states – so far it has hosted astronauts andcosmonauts from 15 nations.
The ISS has come in for a lot of criticism over theyears, mainly to do with cost… and this criticism isnot without merit. The Station has ended up being farmore expensive than planned (no real surprise there)and many have argued that those funds could havebeen better and more effectively spent on unmannedfacilities. That’s probably so, but it bears rememberingthat full-scale operation has only just begun, so onlytime will tell if the money and effort has been worth it.
It is also worth remembering that manned spaceflightis undertaken not just for reasons of exploration andscientific endeavour – it’s also a matter of nationalprestige and technology development. ISS operationsare currently funded and approved through to the year
2020. It seems fairly unthinkable that this will be thelimit of its lifetime – barely 10 years of full operation.It is most likely that its life will be extended, perhapswith contributions from new spacefaring nations, suchas China, and maybe with input from and utilisationby private enterprise.
End of the shuttleFor NASA, it must have seemed that everything wasgoing so well. Construction of the ISS was proceedingsmoothly, and shuttle operations had been routine formany years. Then came the horrifying disintegrationof Columbia during re-entry in 2003, and the biggestshake-up in US manned spaceflight since the end ofthe Apollo era.
The post-Columbia review determined that theshuttles had become too long in the tooth and toounsafe to continue flying without hugely expensivesafety upgrades. The decision was taken to make somesafety improvements to prevent a repeat of Columbia’sfate, and then to finish building the InternationalSpace Station as quickly as possible and pension theshuttles off. This would leave the US without a manned
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 185
The International Space Station is more than 100 metres long, more than 400 tonnes in weight and has an interiorpressurised volume of around 1000 cubic metres. [credit: NASA]
spaceflight capability, and make it reliant on theRussians with their Soyuz capsule to get astronautsinto orbit – not something that pleased everyone inCongress or the spaceflight community.
The USA needed a new vision for space exploration,and it was a case of back to the future – a plan toreturn to the Moon and eventually travel to Mars. Toachieve this, a new crewed capsule would be needed,plus two new rockets… one to loft the capsule intoorbit, and a bigger one to send it plus a lunar moduleto the Moon. The capsule was named Orion and therockets Ares.
So NASA spent more than five years and the betterpart of $US10 billion developing the new systems,only to have the programme cancelled by the newObama administration… one week before the first testlaunch of the first of the new Ares rockets.
This on again, off again approach to manned space-flight has typified the US approach for the past twodecades. The ISS – originally proposed as Space StationFreedom in 1983 – went through numerous wastefulredesigns in the 1980s and 1990s as Congress continuallyshuffled funding and changed the rules in mid-stream.But at least one good thing has come out of the end ofthe shuttle era and the cancellation of Orion… the re-alisation that much of the US’s future in LEO shouldbe turned over to private enterprise.
The new frontierThe USA has decided to relinquish LEO mannedtransport to private ventures. In my opinion, this is avery good move. With the ISS built, America no longerneeds the full capabilities of a space shuttle just to getcrews into space. It simply needs someone to operate ataxi service, regularly, safely and inexpensively.
Aviation was very expensive in its early days –limiting its use to specialised services or to the very
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011186
An International EndeavourMany nations have launched unmanned satellites intospace, including Australia with WRESAT in 1967, but onlythree have had the capability to launch humans intoorbit. Between the Soviet’s slow-and-steady approach,and the USA’s somewhat more dramatic flights – plusnow three manned flights by the Chinese with theirShenzhou craft – a total of 525 individuals from 38nations have flown in space. Of these, 335 have been UScitizens and 113 Soviet/CIS. The overall genderbreakdown is 470 men and 55 women.
Inside the Kibo lab onboard the International SpaceStation (ISS) in May 2011. Twelve astronauts andcosmonauts making up the STS-134 Endeavour and ISSExpedition 27 crews take a break for a group portrait.From left in the front row are Paolo Nespoli (EuropeanSpace Agency), Dmitry Kondratyev (Russia), Mark Kelly(NASA) and Roberto Vittori (ESA). Back row: CadyColeman (NASA) and Russian cosmonauts AndreyBorisenko and Alexander Samokutyaev, along with NASAastronauts Ron Garan, Michael Fincke, Andrew Feustel,Greg Chamitoff and Greg H. Johnson. [credit: NASA]
“Then came the horrifyingdisintegration of Columbiaduring re-entry in 2003,and the biggest shake-up inUS manned spaceflightsince the end of the Apolloera.”
Artist’s impression of the SpaceX Dragon capsule, intendedto conduct supply runs to the International Space Station.[credit: SpaceX]
wealthy – eventually the prices came down asnew technologies made the cost per seat muchlower. In the early days of the Kangaroo Routebetween Australia and the UK, the cost of areturn ticket could have bought you a house –around 130 weeks of average wages. Today, areturn ticket is about two weeks of averagewages. The same reduction in costs is boundto happen with privately run spaceflight too.
And private enterprise has been quick tosee the potential for exploiting LEO services.It is interesting to note that many (thoughnot all) of those competing in the LEO raceare recent entrants rather the traditional, old monolithicaerospace companies.
With some seed money from NASA, several operatorsare developing both unmanned and manned craft tosupply the ISS. Prime among them is SpaceX, foundedby Elon Musk, one of the inventors of PayPal. SpaceXhas already had one very successful test flight of itsDragon unmanned cargo capsule, lofted into orbitatop SpaceX’s own heavy-lift rocket, Falcon 9. Dragon’sfirst operational flight to the ISS could come as early asNovember 2011.
A similar cargo capsule, Cygnus, is being developedby Orbital Sciences Corporation with the first testflight scheduled for late 2011. Then there is SierraNevada Corporation, developing the Dream Chaser, aspaceplane that could carry up to eight people intoLEO. Boeing is working on the CST-100, a reusableApollo-like capsule that could carry seven astronauts.
And the secretive Bigelow Aerospace is working oninflatable space stations – two ‘scale models’ have beenoperating in orbit for several years. Meanwhile, NASAis pushing ahead with a modified version of Orion, in-tended to be able to undertake deep space missions –initially to a near Earth asteroid, and eventually toMars.
The shift to commercialisation of LEO transportservices has been a long time coming, and it promisestwo key benefits. First, it will drive launch and
operational costs down, as competition leads to inno-vation and ‘lean’ business models. And secondly, andperhaps more importantly, it will free up preciouspublic funding. Space agencies such as NASA are attheir best when they apply their limited resources topushing into unknown frontiers, exploring new horizonsand inventing the technologies of tomorrow. It is hightime that private enterprise took over the bus serviceinto LEO, letting national space programmes concentrateon going boldly where they’ve never gone before.
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 187
AUTHOR BIOJonathan Nally is a veteran science writer and broadcaster. He is a recipient of the David AllenPrize from the Astronomical Society of Australia for excellence in communicating astronomy tothe public. He was the founder and editor of Sky & Space, Australia’s first popular-level astronomymagazine, and currently is editor of the Australian astronomy and space news website:www.spaceinfo.com.au.
“With the ISS built, Americano longer needs the fullcapabilities of a spaceshuttle just to get crewsinto space. It simply needssomeone to operate a taxiservice, regularly, safelyand inexpensively.”
Artist’s impression of the Orbital Sciences Corporationunmanned Cygnus spacecraft about to dock with theInternational Space Station. [credit: Orbital SciencesCorporation]
Trevor Lionel Tansley arrived inAustralia in 1976 to take up a lec-tureship in physics at MacquarieUniversity in Sydney. He retired31 years later having made manycontributions, including high impactresearch in semiconductor materialsand physics, and higher degree re-search education. He is rememberedwith affection as an erudite andcultivated man; a skilled commu-nicator, a diplomat, and a supervisorpar excellence to more than 50 re-search students.
Trevor was born in Leicester,England during WWII. He was ed-ucated at Gateway Boys’ GrammarSchool, Leicester 1954–61, andcompleted a Physics Honours degreeat the University of Sheffield in1961–64. He was recruited directlyto the Mullard Research Laboratories(MRL), Surrey, a part of the PhilipsResearch Laboratory Group, wherehe engaged in semiconductor ma-terials and device research. Tun-nelling phenomena in semiconduc-tors and the heterostructure wererecent discoveries. He has ten singleauthor papers on his heterojunctionresearch from 1966–67 alone, allpublished in prestigious journals.
Trevor completed a PhD at Not-tingham University as an externalstudent while working at MRL. Ahighlight of his early career was co-chairing a session at the first Inter-national Conference on the Physicsand Chemistry of SemiconductorHeterojunctions with Leo Esaki(who later shared the 1970 NobelPrize for Physics). In 1974 Trevorsuccessfully applied for a fellowshipin the Department of Electrical andElectronic Engineering at Notting-
ham University, where he achievedthe first known sputter depositionof luminescent ZnO on Si.
After Trevor and his family emi-grated to Australia, he taught widelyin physics and electronics and wasquickly promoted to senior lecturerin 1977. He remained motivatedand energetic to make new oppor-tunities for frontline semiconductormaterials growth, characterisation,and theory research. SupervisingPhD students facilitated this. Hisre-emergence onto the internationalstage was via research on indiumnitride with Don Neely and CathyFoley. A 1986 paper, ‘Optical bandgap in indium nitride’, by Tansleyand Foley in J. Appl. Phys. remainshis most highly cited work with al-most 500 citations. This researchestablished Trevor as one of the vi-sionaries for the significance andimportance of nitride semiconductorresearch. Colleagues, such as Chenu-patti Jagadish at the ANU, haveacknowledged that “Trevor is im-portant internationally as a pioneerof nitride research”.
Trevor authored or co-authored176 journal papers. He establishedthe Semiconductor Science andTechnology Laboratories at Mac-quarie University in the early 1990s,which grew to about 25 staff. Thesuccess in nitride semiconductorresearch ultimately led to BluGlassPty Ltd to commercialise MacquarieUniversity IP developed from ARCfunded research on remote plasmachemical vapour deposition.
Trevor was appointed as Profes-sorial Fellow and the FoundationDean of Graduate Studies at Mac-quarie University in 1996. He had
many international research collab-orations and held external positionsaround the world. He was awardeda DSc by Nottingham Universityand was elected a Fellow of theIEE, both in 1995.
Trevor is a remembered as a rareand delightful man, and an excellentfriend to many in the internationalphysics and electronic engineeringcommunities. He is survived by hiswife Sarah and nine children andstepchildren. He is buried alongsidehis eight-year old son Francis.[Trevor’s life is described more fully atwww.aip.org.au/news/239, along withinformation on how to donate to the‘Professor Trevor Tansley Prize’.]
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011188
OBITUARY
Trevor Tansley (1943 – 2011)Deb Kane, Macquarie University
[credit: Michelle Wilson]
LASTEK–TOPTICA PHOTONICS
Multi-Colour Systems– Multi-Laser Enginesand Tunable VISibleLasersThree exciting new systems are now available from Toptica:
iiChrome MLE-LMulti Laser Engine with up to three diode lasers and one DPSSlaser fully integrated in one compact box.• Multi-line laser with up to four laser lines• Wavelengths diode lasers: 405, 445, 488 and 640 nm (375,
473, 660, 785 nm and others on request)• Wavelengths DPSS laser: 532 and 561 nm (505, 515, 594 nm
and others on request)
iChrome MLE-SAll-diode Multi Laser Engine with up to four diode lasers fullyintegrated in one compact box.• Multi-line laser with up to four diode laser lines• Available wavelengths: 405, 445, 488 and 640 nm (375, 473,
660, 785 nm and others on request)• High free-space and fibre coupled output power levels
Common to both MLE modelsThe individual lasers are efficiently combined and delivered freebeam or via an all-in-one PM/SM fibre output. The microprocessorcontrolled system enables flexible OEM integration. High-speedanalogue and digital modulations allow fast switching of laserwavelength and intensity.
TOPTICA’s ingenious COOLAC technology automaticallyaligns the system with a single push of a button. This featureensures a constant optical output level even under stronglyvarying ambient conditions and completely eliminates the needfor manual realignment – making the iChrome MLE the mostadvanced multi-line laser system on the market.• Single mode, polarisation maintaining fibre output or free
beam COOLAC technology for highest coupling efficiency, ul-timate stability and drop-shipment capability
• Direct modulation and fast switching between wavelengths• True one-box solution with integrated electronics• Unique features: COOLAC, FINE and SKILL technology• Most compact and cost effective solution for multicolour bio-
photonic applications
iChrome TVISOur ultrachrome picosecond laser is:• Continuously tunable in the visible range of 488–640 nm• Fibre coupled output (single-mode)• Fully automated operation• Pure colour, narrow emission bandwidth (<3 nm)• Perfectly suited for fluorescence lifetime imaging microscopy
(FLIM) or optical testing of componentsThe iChrome TVIS laser system is a fibre laser with the
flexibility to set automatically the laser output to any wavelengthin the visible (488–640 nm). The coherent laser output ensuresthat the visible light exhibits the best intensity noise performanceand the use of polarisation maintaining optical components a
stable linear polarisation of the fibre coupled output beam isachieved. The entire laser system is extremely user friendly: Noalignment procedures of any optical components distract the userfrom the main task – to produce results.
DL-RFA-SHG pro 2 Watt@ 589 nm, single linefor sodium coolingThe new DL RFA SHG pro is anarrow-band tunable continuouswave laser for sodium cooling. The system is based on a near-IRdiode laser in the successful ‘pro-design’ (DL 100/pro design,1178 nm), with a subsequent Raman fibre amplifier (RFA) and aresonant frequency doubling stage (SHG pro).
The DL RFA SHG pro features a spectral linewidth below 1MHz and 20 GHz mode-hop free tuning. For system operation,no water cooling and no external pump is required. The powerscalable approach of the DL RFA SHG pro also offers solutionsfor other high power applications such as sodium LIDAR,medical therapy or super resolution microscopy. Customisedsystems with higher output powers up to 10 W are available onrequest. Wavelengths between 560 and 620 nm will soon beavailable as customised solutions.
FemtoFiber pro – the product family isexpandedAfter the successful introduction of theFemtoFiber pro IR, NIR and SCIRmodels, TOPTICA is now taking thefinal step to also include the remainingsystem variants such as tunable visible(TVIS), tunable near-infrared (TNIR) and tunable ultra compressedpulse (UCP). Options such as variable repetition rate (VAR) anda phase-locked loop Laser Repetition rate Control (LRC) byTOPTICA’s well-established PLL-electronics are rounding upthe FemtoFiber pro product family.
The first and fastest of the new models, UCP, shows shortpulses in the range down to 13 fs, the fastest available on themarket from a turnkey SAM modelocked fibre laser system.
The TVIS expands the super-continuum generation (SCIR)by a tunable second harmonic generation and allows transferringfemtosecond pulse generation into the visible wavelength rangefrom 490 to 700 nm.
The TNIR variant finally adds a new feature to the FemtoFiberpro family. As opposed to the TVIS, it uses the high-bandcontinuum (>1560 nm) for second harmonic generation. Thiscontinuum part is a solitonic pulse and therefore needs no pulsecompression. The output wavelength can be tuned from 800 to1100 nm. This variant was not previously available in the FFSproduct family.
For more information please contact Lastek at [email protected] Pty LtdAdelaide University – Thebarton Campus10 Reid St, Thebarton, SA 5031Aus 1800 882 215; NZ 0800 441 005Tel: +61 8 8443 8668 Fax: +61 8 8443 8427e-mail: [email protected] Web: www.lastek.com.au
NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS 189
PRODUCT NEWS
WARSASH SCIENTIFIC
Lightweight Benchtop Vibration Isolation
Warsash Scientific is pleased to announce a new lightweightbenchtop vibration isolation system from Kinetic Systems, Inc.Specifically designed for portability, the ELpF can be easily repo-sitioned on the benchtop, even with a load and in float. Itsunique, self-contained design provides this without causingdamage to the vibration isolators.
An economical alternative to heavy- weight models, the Er-gonomic Low-Profile-Format platform provides vibration isolationfor sensitive devices. It features a load capacity of 100 or 300 lbs.in a light- weight, ergonomic system.
The platform has a low profile (only 3″ high), uses a smalltabletop (16″×19″ standard) and weighs 40 lb, making it veryportable. Ergonomic features include gauges tilted upward foreasier viewing and recessed handles for easy carrying.
Designed for use in laboratories and Class 100 cleanrooms,the ELpF platform is ideal for supporting atomic force micro-scopes, microhardness testers, analytical balances, profilometers,and audio equipment.
Self-levelling and active-air isolation give the platform lownatural frequencies (1.75 Hz vertical, 2.0 Hz horizontal) andtypical isolation efficiencies of 95% (vertical) and 92% (horizontal)at 10 Hz.
Other tabletop sizes can be customised per specifications. Thetop, which can be ordered with or without mounting holes, canbe aluminium plate, ferromagnetic stainless steel, plastic laminate,or anti-static laminate.
For more details on this or other vibration isolation equipment,contact [email protected].
Real-Time Operating System for SystemsIntegrationPI (Physik Instrumente), the leading manufacturer of piezoceramicdrives and positioning systems, offers a real-time module as anupgrade option for the host PC and also the connection of the
GCS (PI GeneralCommand Set) soft-ware drivers. The mod-ule is based on Knop-pix Linux in conjunc-tion with a pre-con-figured Linux real-timeextension (RTAI).
The use of real-timeoperating systems on
the host PC allows it to communicate with other systemcomponents, e.g. a vision system, without time delays withdiscrete temporal behaviour and high system clock rate.
A library which is 100% compatible with all other PI GCS li-braries is used for the communication with the real-time system.All PI GCS host software available for Linux can be run on thissystem.
The real-time system running in the real-time kernel can beused to integrate PI interfaces and additional data acquisitionboards for control. Open functions to enable you to implementyour own control algorithms are provided. Data, such as positionsand voltages, is recorded in real time, and pre-defined tables, withpositions, for example, are output in real time to the PI interfaceand to additional data acquisition boards.
You can program your own real-time functions in C/C++,MATLAB/ SIMULINK and SCILAB.
The system includes a PI GCS server, which allows the systemto be operated as a blackbox using TCP/IP, via a Windowscomputer, for example.
The system can be installed on a PC or booted directly as a liveversion from the data carrier. A free demo version with restrictedfunctionality is available.
For more information on the real time operating software or other PIpositioning equipment, contact [email protected].
E-618: 3.2 kW Peak Power for New PiezoAmplifier
Available from Warsash Scientific is the new PI (Physik Instrumente)E-618 high power amplifier for ultra-high dynamics operation ofPICMA® piezo actuators.
The amplifier can output and sink a peak current of 20 A inthe voltage range between -30 and +130 V. The high bandwidthof over 15 kHz makes it possible to exploit the dynamics of thePICMA® actuators. This type of performance is required in activevibration cancellation and fast valve actuation applications.
The E-618 also comes with a temperature sensor input to shutdown the amplifier if the maximum allowed temperature of thepiezo ceramics has been exceeded. This is a valuable safety featuregiven the extremely high power output.
The E-618 is available in several open-loop and closed-loopversions with analogue and digital interfaces.
For more information on these and the range of other PI products,contact [email protected] Scientific Pty LtdTel: +61 2 9319 0122 Fax: +61 2 9318 2192Web: www.warsash.com.au
190 AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011
COHERENT SCIENTIFICIntroducing the new SG384 4GHz RF SignalGenerator
The SG384 uses a unique, innovative architecture (Rational Ap-proximation Frequency Synthesis) to deliver ultra-high frequencyresolution (1 μHz), excellent phase noise, and versatile modulationcapabilities (AM, FM, øM, pulse modulation and sweeps) at afraction of the cost of competing designs.
Features:• DC to 4.05 GHz • 1 μHz resolution • AM, FM, øM, PM and sweeps • OCXO timebase (std) • -116 dBc/Hz SSB phase noise (20 kHz offset, f = 1 GHz) • Rubidium timebase (opt.) • Square wave clock outputs (opt.) • Analog I/Q inputs (opt.) • Ethernet, GPIB and RS-232 interfaces
The standard model SG384 produces sine waves from DC to4.05 GHz. There is an optional frequency doubler (Opt 02) thatextends the frequency range to 8.10 GHz. Low-jitter differentialclock outputs (Opt 01) are available and an external I/Qmodulation input (Opt 3) is also offered. For demanding appli-cations, the SG384 can be ordered with a rubidium time base(Opt 04).
Stanford Research Systems Photon CounterThe SR400 Dual-Channel Gated Photon Counter from StanfordResearch Systems offers a convenient, integrated approach tophoton counting that avoids the complexity and expense of oldcounting systems. No longer is it necessary to mix and matchamplifiers, discriminators, gate generators and counters. TheSR400 combines all these modules into a single, integrated, mi-croprocessor controller instrument. Complete measurement taskssuch as background subtraction, synchronous detection, sourcecompensation and pile-up correction can all be performed easilywith the SR400.
Features:• Two independent counting channels • Count rates to 200 MHz • 5 ns pulse-pair resolution • Gated and continuous modes • Gate scanning for time-resolved counting • Built-in discriminators • Gate and discriminator outputs • GPIB and RS-232 interfaces.
Stanford Research Systems MultichannelScaler
The SR430 is the first multichannel scaler which combinesamplifiers, discriminators, bin clocks, and data analysis in asingle, integrated instrument. With its many features and itseasy-to-use menu driven interface, the SR430 simplifies time-resolved photon counting experiments. The SR430 MultichannelScaler/Averager can be thought of as a photon counter thatcounts events as a function of time. A trigger starts the counterwhich segments photon count data into sequential time bins (upto 32k bins). The width of the bins can be set from 5 ns to 10 ms.The instrument records the number of photons that arrive ineach bin.
Features:• 5 ns to 10 ms bin width • Count rates up to 100 MHz • 1k to 32k bins per record • Built-in discriminator • No interchannel dead time • On-screen data analysis • Hardcopy output to printers/plotters • DOS compatible 3.5-inch drive • GPIB and RS-232 interfaces.
Coherent IncEnergyMaxLaser SensorsEnergyMax-USB/RSsensors contain minia-turised meter electron-ics that are integratedwithin the sensor cable.Coherent’s entire rangeof high performanceEnergyMax sensors are available in this form factor with eitherRS-232 or USB 2.0 connectivity enabling measurement of theenergy per pulse or average power of pulsed lasers from thenanojoule to the multi-joule level, over wavelengths from thedeep ultraviolet through the far infrared, and from single pulsesto repetition rates of 10 kHz (with measurement of every pulse).Additionally, multiple EnergyMax sensors can share a trigger(internal or external) for synchronised operation, such as toenable pulse ratiometry.
Features:• EnergyMax-USB/RS sensors provide USB connectivity for
R&D and production environments, and USB 2.0 for OEMembedded applications
• Low cost of ownership
191NOV–DEC 2011 | 48(6) AUSTRALIAN PHYSICS
• Fast 16-bit A/D converter supports measurement accuracysimilar to that found in LabMax-TOP meter
• Ability to log every pulse at data rates up to 10 kHz directly toa file
• Truly synchronised dual unit operation to support ratiometry>1 kHz every pulse
• State-of-the-art EnergyMax Sensor Technology.For further information on all four products, please contactMargaret Davies: [email protected] Scientific116 Sir Donald Bradman Drive, Hilton, SA 5033Tel: +61 8 8150 5200 Fax: +61 8 8352 2020Web: www.coherent.com.au
AGILENT TECHNOLOGIESHigh Resolution Wide Bandwidth ArbitraryWaveform Generator
Agilent Technologies has added a high-resolution, wide-bandwidth,8- or 12-GSa/s modular instrument to its portfolio of arbitrarywaveform generators. The new M8190A arbitrary waveform gen-erator is able to deliver simultaneous high resolution and widebandwidth along with spurious-free dynamic range and very lowharmonic distortion.
This functionality allows radar, satellite and electronic warfaredevice designers to make reliable, repeatable measurements andcreate highly realistic signal scenarios to test their products.
The M8190A helps engineers:• build a strong foundation for highly reliable satellite commu-
nications• generate multilevel signals with programmable ISI and jitter
up to 3 Gb/s.The M8190A offers:
• 14 bits of resolution and up to 5 GHz of analog bandwidthper channel simultaneously
• the ability to build realistic scenarios with 2 GSa of waveformmemory
• reduced system size, weight and footprint with compactmodular AXIe AWG capability. The high performance of the M8190A arbitrary waveform
generator is made possible by a proprietary digital-to-analogconverter (DAC) designed by the Agilent Measurement ResearchLab. Fabricated with an advanced silicon–germanium BiCMOSprocess, the DAC operates at 8 GSa/s with 14-bit resolution andat 12 GSa/s with 12-bit resolution. At 8 GSa/s, the Agilent DACdelivers up to 80c-dB SFDR.
More information is available at www.agilent.com.au/find/M8190.
Agilent PCIe® High-SpeedDigitiserAgilent U1084A is a dual-channel, 8-bit PCIe digitiser with up to 4 GS/ssampling rates, 1.5 GHz bandwidthand incorporates a 15 ps trigger timeinterpolator for accurate timing meas-urement.
The U1084A’s digitiser technologycombines fast analog-to-digital con-verters with on-board field programmable gate array technologyallowing original equipment manufacturers to easily design-inhigh-speed signal acquisition and analysis.
More information is available at www.agilent.com.au/find/u1084a.
One Box EMI Receiver that EnhancesCompliance Testing
Agilent Technologies has announced the introduction of theN9038A MXE EMI receiver, which is designed for laboratoriesthat perform compliance testing of electrical and electronicproducts. The MXE enhances electromagnetic interference (EMI)measurement accuracy and repeatability with a displayed averagenoise level of -163 dBm at 1 GHz. This represents excellent inputsensitivity, an essential receiver attribute that reduces the effectsof electrical noise.
The MXE is fully compliant with CISPR 16-1-1 2010, theInternational Electrotechnical Commission recommendation thatcovers measurement receivers used to test conducted and radiatedelectromagnetic compatibility of electrical and electronic devices.With outstanding measurement accuracy of ±0.78 dB, the MXEexceeds CISPR 16-1-1 2010 requirements.
The built-in suite of diagnostic tools, including meters, signaland measurement lists, markers, span zoom, zone span and spec-trogram displays, makes it easy to monitor and investigate problemsignals. The MXE is also an X-Series signal analyser capable ofrunning a variety of measurement applications such as phasenoise. By enhancing the analysis of noncompliant emissions,these capabilities enable EMI test engineers and consultants toevaluate signal details and deliver new insights about the productsthey test.
More information is available at www.agilent.com.au/find/MXE.For further details, contact [email protected] Technologies Australia Pty LtdTel: 1800 629 485Web: www.agilent.com.au/find/promotion
AUSTRALIAN PHYSICS 48(6) | NOV–DEC 2011192
31 January – 3 February 2012Thirty-sixth Annual Condensed Matter & Materials MeetingCharles Sturt University, Wagga Wagga, NSW
14 – 16 February 2012Pathways to SKA Science in AustralasiaSKANZ Conference, Auckland, New Zealand
17 – 18 February 2012Physics Teachers ConferenceMonash University, Melbourne, VIC
25 February 2012Queensland Astronomy Education Conference (QAEC)Brisbane, QLD
4 – 11 July 2012Thirty-sixth International Conference on High EnergyPhysics, ICHEP2012Melbourne Convention and Exhibition Centre, VIC
30 July – 3 August 2012ANU Nuclei in the Cosmos Winter SchoolANU, Canberra, ACT
5 – 10 August 2012Nuclei in the Cosmos 2012Cairns Convention Centre, QLD
12 – 17 August 2012Seventy-fifth Annual Meeting of the Meteoritical SocietyCairns Convention Centre, QLD
23 – 28 September 2012Thirty-seventh International Conference on Infrared,Millimetre and Terahertz WavesWollongong, NSW
18 – 23 November 2012Fifteenth International Conference on Small-angleScattering, SAS 2012Sydney, NSW
CONFERENCES IN AUSTRALIA 2012
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