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News and Reviews in
Astronomy & Geophysics
June 2014 • Vol. 55 • Issue 3
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Galaxies, gravity background is transparent
and structure
Quantum telescopes • Do we need dark Advancing
Astronomy and
energy? • Sunspots past and present Geophysics
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&
Contents
News and Views
NEWS AND REVIEWS IN
4 Editorial: Looking back, looking forward •
ASTRONOMY & GEOPHYSICS Astonishing and glorious: for 200 years • Funding
boost – and new research vessel • Art at
Astronomy & Geophysics publishes news reviews
and comment on topics of interest to astronomers NAM2014 • BICEP2 builds body of evidence for
and geophysicists. Topical material is preferred.
Publication will be as fast as is compatible with inflation • Astrophotographers and space
referees’ and authors’ responses. Contact the Editor
or see http://www.ras.org.uk for further information. telescopes join forces • First Earth-size planet in
Editor: Sue Bowler HZ • Free iBook ‘A Big Ball of Fire’ • Galactic
School of Earth and Environment,
University of Leeds, Leeds LS2 9JT, UK magnetic fingerprint from Planck • A short day on
Tel: +44 (0)113 343 6672
Email: s.bowler@leeds.ac.uk Beta Pictoris b • Early-career astrobiologists forge
Management Board links • Exomoon found? • Slow slip after quake.
Chair: Ian Crawford Birkbeck College, Univ. of London Flooding in detail on Mars, p8
8 Mission update: Mars Express, Cassini, LADEE.
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Pamela Mortimer RAS
Robert Massey RAS
Mike Cruise RAS
Editorial Advisors
Andrew Ball Noordwijk
Features
Tom Boles Coddenham
Allan Chapman Oxford University 10 RAS Ordinary Meeting
Roger Davies Oxford University
Mike Edmunds University of Wales, Cardiff Reports from the January 2014 meeting.
Jane Greaves University of St Andrews
Mike Hapgood Rutherford Appleton Laboratory
Richard Holme University of Liverpool 11 Q&A: Martin Barstow
Ian Howarth University College London
David Hughes Sheffield The President of the RAS, 2014–16.
Katherine Joy University of Manchester
12 Dark energy, paradigm shifts
Margaret Penston IoA, Cambridge
Claire Parnell University of St Andrews
Roberto Trotta Imperial College London
Althea Wilkinson University of Manchester
The Council of the RAS
and the role of evidence
Ofer Lahav and Michela Massimi examine the
Burlington House, Piccadilly, current state of the Standard Model of cosmology
London W1J 0BQ In profile: RAS President Martin Barstow, p11
Tel: (0)20 7734 4582 or 3307 in a historical and philosophical context.
Fax: (0)20 7494 0166
16 The Great Melbourne Telescope
Email: info@ras.org.uk
Web: http://www.ras.org.uk
Opening Hours Ragbir Bhathal traces the chequered history of the
(Monday to Friday)
Offices: 9.30–17.00 Great Melbourne Telescope in Australia, from
Library: 10.00–17.00
Staff Contacts
initial disappointment to recent research success.
Executive Secretary
Pamela Mortimer pm@ras.org.uk
RAS Communications Officer
20 Science enabled by the
Robert Massey rm@ras.org.uk
Global Exploration Roadmap
Ian Crawford summarizes a meeting which
examined how science stands to benefit from the
Produced for the RAS by Oxford University Press,
Global Exploration Roadmap.
Great Clarendon Street, Oxford OX2 6DP, UK
Tel: +44 (0)1865 353895. Email: astrog@oup.com
24 Sunspots from the past, The Great Melbourne Telescope, p16
This journal is available online at:
http://www.astrogeo.oxfordjournals.org treasures for today
Subscriptions: http://oxfordjournals.org/our_ Rainer Arlt examines the sunspot observations of
journals/astrogeo/access_purchase/price_list.html
Samuel Schwabe, a 43-year record of the solar
Design and production:
Paul Johnson http://www.higgs-boson.com cycle, now digitized and available for research.
Printed by C.O.S. Printers Pte Ltd, Singapore
ISSN 1366-8781 (print), ISSN 1468-4004 (online)
28 Quantum telescopes
©2014 RAS and individual contributors. All rights Aglae Kellerer speculates about the possibilities
reserved. Authorization to photocopy items for
internal or personal use, or the internal or personal quantum physics offers for a new generation of
use of specific clients, is granted by the RAS for
libraries and other users registered with the telescopes.
Copyright Clearance Center Transactional Reporting
Service, provided that the base fee of $15 per copy
is paid directly to CCC (http://www.copyright.com). 33 The cosmic velocity field
Special requests should be addressed to the Editor.
The peculiar velocities of galaxies hold the promise
Disclaimer The contents and views expressed in
A&G are the responsibility of the Editor. They do not of probing how gravity forms structures. Yin-Zhe
represent the views or policies of the RAS or Oxford
University Press, except where specifically identified Ma and Douglas Scott delve into the details.
as such. While great care is taken to provide accurate
and helpful information and advice in the journal, the
RAS, its Council and the Editor accept no responsibility 37 Lights in the sky: a search for meaning
for errors or omissions in this or other issues.
Martin Ward sets the scene for a public panel
A&G (ISSN 1366-8781) is published bimonthly.
A&G is distributed by Mercury Media Processing, discussion on “lights in the sky” as seen through Cover: The relative motion of galaxies – here is the
1634 E. Elizabeth Ave, Linden, NJ 07036, USA.
Periodicals postage paid at Rahway, NJ and at different cultural and historical lenses. cluster Abell 2744, containing some of the faintest
additional entry points. US Postmaster: send address
changes to A&G, c/o Mercury Media Processing, and youngest galaxies known, in a Hubble Space
1634 E. Elizabeth Ave, Linden, NJ 07036, USA.
Society News Telescope image – holds the key to the formation
of structure in the universe, as explained by Yin-
39 Comedy, crochet and coding come to NAM2014 • Khe Ma and Douglas Scott on pages 3.33–3.36 of
The 25th RAS Annual Picnic • RAS Research this issue. (NASA, ESA and J Lotz, M Mountain, A
Fellows • Consider RAS grants • New Fellows. Koekemoer and the HFF Team [STScI])
A&G • June 2014 • Vol. 55 3.3
News
Editorial Astonishing and glorious: for 200 years
Looking back, The Royal Astronomical Society
looking forward has announced a major bicenten-
nial project, to spend £1m in order
Sue Bowler, to extend the reach of astronomy
Editor and geophysics into new areas,
building on the popularity of these
This is
sciences to engage and entice
traditionally
those who do not currently engage
a time for
the RAS to with our science, or any sciences.
look forward, The trigger for “Astonishing Astron-
having omy and Glorious Geophysics”, a
reviewed the major development of the Society’s
past year at outreach and engagement work, is its
200th anniversary in 2020. The RAS
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the Annual General Meeting. This
year the Society is planning ahead is investing £1m from its reserves to
on a very big scale. “Astonishing fund 10–20 major projects, some of
Astronomy and Glorious which may require additional fund-
Geophysics”, launched at the May ing from other sources.
AGM, is a game-changing project The goal is to fund fewer, larger
for engagement and outreach, in projects, with the aim of producing Outreach towards new audiences could work where people gather outside
subjects already known for their by 2020 a well-founded legacy of after dark for entertainment – such as music festivals. Since 2011 Jodrell
popular appeal. But the RAS wants projects that embed astronomy and Bank has hosted shows combining music (Elbow, The Flaming Lips, Sigur
to spread the net much more geophysics in a much wider commu- Rós – pictured here) with science activities and workshops. (Tom Martin)
widely, finding ways to engage new nity. The goal is to ensure that our
audiences with the fascination and sciences retain their appeal, continue plans to approach other bodies such who might be inspired by the RAS
challenge of our sciences. to inspire people young and old, and as the National Autism Society. financial commitment to co-sponsor
It’s a great way to celebrate a set the RAS on course for the next The RAS is looking for new audi- individual projects or Astonishing
birthday – not by looking back, 200 years as an outward looking ences, novel partnerships and “out of Astronomy and Glorious Geophys-
feeling as if our best days are society that actively supports and the box” ideas, and encourages par- ics itself, please send the details too.
behind us, but by taking up new underpins its sciences. ticipation from Fellows in all fields, The first stage of the project
challenges and setting out to The Society is looking for ideas, not least in spreading the news of this involves targeted consultation of
make the next 200 years better initially among our own committed project. It is expected that bids for the astronomy and geophysics com-
than the first. So, the call is out for and enthusiastic membership, mak- projects on this scale will come from munities, to identify potential stake-
partners, projects and whole new ing use of their talents and individual groups including scientific and other holders, with a stakeholders meeting
ways to embed astronomy and and local networks. However, the stakeholders, and the Society hopes on 16 July, followed by further dis-
geophysics in the lives of many success of Astonishing Astronomy to engage Fellows in finding those semination and town hall meetings
more people, reaching not just the and Glorious Geophysics will depend partners. in several locations in the autumn.
enthusiasts who currently come on establishing partnerships in new Specifically, if Fellows know of Interested consortia will be invited to
to talks and science festivals, but areas, through groups that the RAS potential stakeholders who could submit short proposals in early 2015,
the very many who don’t even does not currently work with. The become partners or leads in Aston- with around five of these invited to
consider doing so. The RAS wants Society has already made contact ishing Astronomy and Glorious submit full bids in 2015.
your ideas, however novel, whacky with, for example, the Prince’s Trust, Geophysics projects, please send The bidding process will be
or just plain odd, because they
the Woodcraft Folk, the National their details to the Executive Secre- repeated in 2015/2016. Full details
might just be the ones that take
Trust, English Heritage and the tary and Deputy Executive Secretary. are available on the RAS website.
off – just look at how social media
Royal Parks, among others, and Or if you know of potential sponsors http://www.ras.org.uk
has changed stargazing.
Of course, while Astonishing
Astronomy and Glorious
Geophysics is intended to change Funding boost – and a new research vessel
astronomy and geophysics
outreach, it is not entirely Soon after the announcement of
altruistic. Talk to successful £113m investment for the UK in
scientists about what inspired the Square Kilometre Array and
them to start their careers the Planetary Transits and Oscilla-
and there is usually a key tions mission (PLATO), Chancellor
event, perhaps watching the George Osborne also announced
Apollo landings or seeing the a new £200m polar research ves-
aftermath of an earthquake. If sel to work in both the Arctic and
the RAS and the new and diverse Antarctic.
partnerships that the Society is The new research ship, with labo-
making can develop a new level ratories on board, plus robotic sub-
of inspirational outreach, then we marines and onboard and remotely
will also be planting the seeds operated instruments, will extend
of future scientists. Astonishing the UK’s research capability in
Astronomy and Glorious extreme polar environments. Better
Geophysics has a potential double endurance and helicopter facilities
whammy: inspiring the scientists will bring better geographical cover-
of the future at the same time as age than the existing research vessels Artist’s impression of the new UK polar research ship.
building a wider public interest in that it will replace.
and support for our sciences. The new ship will be available to tic Survey, part of the Natural Envi- the continuing British presence in
s.bowler@leeds.ac.uk the whole research base in the UK, ronment Research Council. It will Antarctica and the South Atlantic.
and operated by the British Antarc- clearly demonstrate and reinforce http://bit.ly/1ot6x11
3.4 A&G • June 2014 • Vol. 55
News
News in Brief
CTA site selection
Negotiations began in April
to decide on the site of the
Cherenkov Telescope Array (CTA)
in the southern hemisphere.
One site will be selected at
the end of the year, either Aar
in Namibia or the European
Southern Observatory in Chile,
with Leoncito in Argentina
as a reserve. It is hoped that
negotiations will start soon for
the northern hemisphere site.
CTA is a multinational, worldwide
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project to construct a unique
instrument exploring the cosmos
at the highest photon energies.
It will provide an order-of-
magnitude jump in sensitivity
over current instruments,
providing novel insights into
some of the most extreme
processes in the universe.
http://bit.ly/1uEICjw
New station for ILT
Construction of a new German
station close to Hamburg
for the International LOFAR
Telescope (ILT) has been agreed
by ASTRON (the Netherlands
Institute for Radio Astronomy),
the University of Hamburg and
Bielefeld University. This will
boost the overall sensitivity and
the ability of the ILT to image fine
details in celestial objects. LOFAR
is also a recognized science and
technology pathfinder facility
for the next-generation radio
telescope, the Square Kilometre
Array (SKA). ASTRON is now
taking many concepts of LOFAR,
in particular the (real-time
Art exhibition at NAM2014
and off-line) handling of huge
data streams, to the next level
in preparation for the SKA.
Those attending the National Astronomy Meeting 2014 in Portsmouth in June can visit a thought-provoking Production of hardware for a
exhibition by conceptual artist Xavier Poultney entitled Transient Objects. This is a broad project that uses the LOFAR antenna station, which
Sloan Digital Sky Survey (SDSS) as the starting point for a larger investigation into the progression of ideas or consists of hundreds of antennas
the stratification of paradigms leading up to our current one. This image from the exhibition shows the SDSS and advanced electronics, is
CCD array – now in store at the Smithsonian, USA – defunct and ignored as a relic of progress. “I’m interested in contracted out to industry to a
the incompatibility of different explanations of reality, but also in the veins of human intuition or feeling that run value of more than €1m.
through all this evolution of knowledge,” says Poultney. “This instrument was once so cutting edge that it had to http://bit.ly/RtWJJ3
be conceived with components that were not at the time even possible to make, relying on projected technological
capabilities using Moore’s Law.” The exhibition includes both photographs and sculptures. UKSA growing
http://www.nam2014.org/public/exhibitions The UK Space Agency is growing
– with extra government funding
increasing staff numbers to 60
– and a reorganization to ensure
BICEP2 builds body of evidence for inflation that it can meet ambitious plans
for the UK space sector. The
Results from the Background expansion of the universe just after frozen-in quantum fluctuations – rip- UKSA intends to increase the
Imaging of Cosmic Extragalac- the Big Bang, proposed by Alan Guth ples in space-time – that the BICEP2 UK share of “space-enabled”
tic Polarization telescope at the in 1980. Models suggest that quan- researchers think they have identified. industry – expected to become
South Pole suggest that inflation tum fluctuations during inflation These gravitational waves have left a worth £400 billion – to 10% and
at the start of the evolution of the would give rise to the subtle density characteristic polarization pattern increase the turnover of the UK
universe left a mark in the B-mode fluctuations of the CMB observed in the CMB, seen at scales of a few space industry to £19 billion by
polarization of the cosmic micro- by the Wilkinson Microwave Ani- degrees across, making an origin in the year 2020.
wave background (CMB). sotropy and Planck satellites. But it foreground contamination unlikely. http://www.bis.gov.uk/ukspaceagency
Inflation is the brief but superfast is gravitational waves arising from http://bicepkeck.org
A&G • June 2014 • Vol. 55 3.5
News
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Astrophotographers and space telescopes join forces
A new form of professional and amateur collaboration in astronomy has seen amateur astrophotographers combining their images with data from the
Chandra and Spitzer space observatories in a multiwavelength project called Astro Pro-Am. The image of Centaurus A shown here includes X-rays from
Chandra in purple, infrared emission from Spitzer in red and the optical data are shown in red, green, and blue. The optical image was taken by amateur
astronomer Rolf Olsen with a 10-inch telescope he built himself. The jet from CenA shows very clearly in X-rays (purple) but the fine optical image produced
by Olsen also shows evidence for it at optical wavelengths. The Astro Pro-Am collaboration also involves the work of another amateur observer, Detlef
Hartmann, and is a great way to raise interest and awareness among the amateur community of the wealth of data available in NASA’s mission archives.
(X-ray: NASA/CXC/SAO; Optical: Rolf Olsen; Infrared: NASA/JPL-Caltech)
http://chandra.harvard.edu/photo/2014/proam/index.html
First Earth-size Teenagers publish free iBook ‘A Big Ball of Fire’
planet in HZ Teenagers from an east London Laboratory were on hand as subject ate solar flares, and see sunspots for
school have combined the solar experts to answer their questions. themselves with a sunspotter.
The Kepler mission has tracked corona, cupcakes and creative The students, aged 12 and 13, gained “As a scientist, I think this is a
down the first planet in a star’s science to produce a free iBook, creative insights from Lydia Thorn- fantastic opportunity for our stu-
habitable zone comparable in size which they launched at the Science ley of Lt Design and Richard Healey dents,” said Chinye Jibunoh, prin-
to Earth: Kepler-186f. Museum as part of the Beyond from Learn Extreme. cipal of Eastlea Community School.
Kepler-186 is a five-planet system Earth Festival on 7 March this year. Dr Mason said: “I was very happy “It makes me so proud to see how
about 500 light-years from Earth in The book – A Big Ball of Fire – is to share my passion for the Sun with enthused the students are. Science is
the constellation Cygnus, orbiting an engaging mixture of informa- the students. They have taken this fun and interesting. This book helps
an M dwarf star. Kepler-186f has a tion, illustrations and images, vid- iBook project on with great enthusi- to spread that message.”
radius 10% larger than Earth; plan- eos, quizzes and fun craft activities asm and imagination, reaching levels The iBook project was developed
ets of this size are generally rocky (including Sun-themed cupcakes!) way beyond my expectation.” by Heather MacRae of Venture
bodies. It orbits closer to its star than designed to inspire interest in the The students from Eastlea Com- Thinking, with ICT expertise from
Earth is to the Sun, with a period of Sun. The book includes interviews munity School in east London began Learn Extreme and was funded by
130 days, but the host star has a mass with a range of female and ethnic the project in March 2013 by iden- the UK Space Agency, Eastlea Com-
half that of the Sun so the planet minority scientists from postgradu- tifying reader interests and the sort munity School and STFC. “A Big Ball
receives less energy than Earth does. ate students through to professors. of questions they would ask about of Fire has been a terrific learning
This puts it in the habitable zone, Dr Helen Mason, from DAMTP, solar physics. The authors visited the experience,” said MacRae. “Helen,
with liquid water possible at its sur- Cambridge University and the Institute of Astronomy, Cambridge Lucie and Carolin have shared ideas
face, but its atmosphere is unknown Sun|Trek project (http://www.sun- University, to meet and interview and content and have been terrific
so estimates of surface temperature trek.org), Prof. Carolin Crawford astronomy and astrophysics students role models for women in science. But
are imprecise. The team published from the Institute of Astronomy, who shared tips for future study. the students have been the authors
the discovery in Science. Cambridge University, and Dr Lucie They also had a chance to observe and editors and the real stars.”
http://1.usa.gov/1s6lTZK Green from Mullard Space Science the Sun with a solar telescope, to cre- http://bit.ly/1j6mu8c
3.6 A&G • June 2014 • Vol. 55
News
Galactic magnetic fingerprint from Planck News in Brief
Exomoon found?
The first exomoon candidate
has been identified through
gravitational microlensing, by a
joint Japan–New Zealand–US
team. Lensing by a foreground
star is slightly augmented by
an orbiting planet; if the lensing
object – unknown in this case – is
a free-floating planet, the extra
lensing effect could indicate a
moon. In this study, the ratio of
the larger body to its smaller
companion is 2000:1. Depending
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on the distance of this system
(MOA-2011-BLG-262) from
Earth, this could be a small star
with a planet around 18 times
the mass of Earth, or a planet
more massive than Jupiter plus
A first map of the galactic magnetic field, based on observations of polarized light from interstellar dust, has been a planet less massive than Earth.
produced using data from ESA’s Planck satellite. Spinning dust grains throughout our galaxy become preferentially These results are published in
aligned with their long axes parallel to the magnetic field. The light then scattered is polarized; Planck measured the The Astrophysical Journal.
degree and orientation. The map shows areas of stronger polarized emission in darker colours, with the striations http://1.usa.gov/1hBMcls
running in the direction of the field lines projected into the sky, in the Mollwiede projection of the whole sky. The field
is predominantly parallel to the galactic plane, but there is considerable variation above and below. Further data Date for E-ELT blasting
analysis will improve the map by the time of full data release in late 2014. (ESA and the Planck collaboration) The European Extremely Large
http://bit.ly/1mF9BKL Telescope comes another step
closer with the blasting of the
top of Cerro Armazones, the
A short day on Early-career astrobiologists 3000 m mountain in Chile where
the telescope will be built.
Beta Pictoris b forge links in Edinburgh The detonation is scheduled
for 19 June and the European
Researchers using ESO’s Very Mark Fox-Powell, Casey Bryce life. Each person spent 20 minutes Southern Observatory is holding
Large Telescope at Paranal in Chile and Duncan Forgan recount the discussing each topic in a small a ceremony to mark the event as
have determined the length of the success of a one-day workshop group before moving on to another, a milestone in the development
day on an exoplanet for the first organized by the UK Centre for generating five separate mind maps of the biggest optical/infrared
time: 8 hours on Beta Pictoris b. Astrobiology, in conjunction with full of ideas and questions. Based on telescope in the world.
Beta Pictoris b was discovered six the Scottish Universities Phys- these discussions, attendees then pro- http://www.eso.org/sci/facilities/eelt
years ago and was one of the first ics Alliance and the Astrobiology posed specific projects that require
exoplanets to be imaged directly. Society of Britain. interdisciplinary collaboration. Ideas Slow slip after quake
Its rotation rate was determined The core aims of “Building Habit- included experiments with microbes A major 2010 earthquake in
through high-dispersion spectros- able Worlds” on 21 February were under simulated martian conditions, northern Mexico led to slow
copy using the CRIRES instrument to bring together young researchers review papers on several interdisci- movements on faults across
on the VLT by a team of Dutch from different science backgrounds plinary topics and an online resource Southern California. The slip
observers from Leiden University who share a common interest, and to to facilitate better communication on the faults was diffuse and
and the Netherlands Institute for nucleate astrobiology collaborations. between astronomers and micro spread over a wide area, but did
Space Research (SRON). We kicked off with a session of five- biologists. Everyone was encouraged not register on seismometers.
Beta Pictoris b is a young planet, minute “pitches”, in which everyone to volunteer for a project, and the Geophysicists mapped the slip
only 20 million years old and 16 introduced themselves and their teams have agreed to submit updates using the millimetre-scale
times larger than Earth, that orbits research interests or expertise. Top- to the workshop organizers. distortion of the ground revealed
its host star at 8 au. The team found ics and interests included exoplanet The event was a resounding suc- by NASA’s Uninhabited Aerial
that it spins once every eight hours, detection, preservation and detection cess and delegates were extremely Vehicle Synthetic Aperture
giving it an equatorial rotation veloc- of biosignatures, synthetic biology positive. Their enthusiasm reflects Radar (UAVSAR), which flies
ity of nearly 100 000 km/hr (more for space exploration, microbial life the eagerness among early-career on a NASA C-20A aircraft.
than double that of Jupiter). in extreme environments, geomicro researchers for communicating The slip was equivalent to
“It is not known why some planets biology and planetary simulation. We between disciplines – so essential in movement of 36 mm on a 30 km
spin fast and others more slowly,” even heard from a social anthropolo- astrobiology. Events like this encour- long fault, with smaller slips
says co-author Remco de Kok of gist interested in the societal impact age researchers to engage with other on shorter fault segments.
Leiden Observatory and SRON, and perception of astrobiology. fields early in their careers, building Overall, the slip released as
“but this first measurement of an In the afternoon, Duncan Forgan, the vocabulary for collaboration. It much energy as an earthquake
exoplanet’s rotation shows that the a postdoctoral researcher at Edin- was also a unique opportunity for of magnitude 4.9 to 5.3. The
trend seen in the solar system, where burgh’s Royal Observatory, led a early-career researchers to discuss balance between fast slip on
the more massive planets spin faster, brainstorming session on topics as and generate ideas with their peers in faults, giving rise to potentially
also holds true for exoplanets. This diverse as: the distribution of habi- a low-pressure environment without damaging earthquakes, and this
must be some universal consequence tats in the universe, recognizing and supervisors or potential employers. sort of slow slip is an important
of the way planets form.” identifying biosignatures, the co- PhD students at the University of component of seismic hazard
This research by Snellen et al. was evolution of planetary environments Glasgow have volunteered to host a models.
published in Nature on 1 May 2014. and the biosphere, and understand- follow-up event next year. http://1.usa.gov/1m52att
http://www.eso.org/public/news/eso1414 ing the limits of life and the fate of http://bit.ly/QhrTma
A&G • June 2014 • Vol. 55 3.7
News • Mission Update
Space Shorts
Rosetta sights target
ESA’s comet-chasing
mission Rosetta has spotted
its destination, comet 67P/
Churyumov-Gerasimenko,
Mission update
after waking from deep-space
hibernation earlier this year.
The spacecraft used the OSIRIS
(Optical, Spectroscopic and
Infrared Remote Imaging
System) wide-angle and narrow-
angle cameras to image the
comet with exposure times of
between 60 and 300 seconds,
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as “first light” images during
instrument commissioning.
Rosetta carries 11 instruments
and a lander called Philae, and
will arrive at the comet in August.
http://bit.ly/1lUHOD4
LADEE’s lunar impact
NASA’s Lunar Atmosphere and
Dust Environment Explorer
(LADEE) spacecraft hit the far
Catastrophic flood regions on Mars
side of the Moon as planned on
17 April, after a mission finale
that included orbiting the Moon
at an altitude of 2km – closer The High Resolution Stereo Camera on ESA’s Mars Express spacecraft has highlighted details of the fast-flowing
than most commercial airliners water and catastrophic flooding that carved a gorge south of the southeastern rim of the vast Valles Marineris
fly above Earth. LADEE had canyon system. The image above shows the central portion of Osuga Valles, an outflow channel that empties
been collecting data since 10 into a region of chaotic terrain in a 2.5 km deep depression (shown in the lower part of the images, in yellow and
November 2013 and, as well as green). The water may have formed a lake there, or simply soaked into the surface. Osuga Valles shows erosion
examining the lunar atmosphere patterns characteristic of fast-flowing water, such as sets of parallel narrow grooves in the valley floor. The
and dust, it demonstrated a direction of flow is indicated by the streamlined shapes of the islands and the gradient of the valley floor. The
new form of communication HRSC images are also detailed enough to show elevation changes and cross-cutting relationships of channels
between spacecraft and Earth. around the islands, indicating that there were several episodes of flooding. (ESA/DLR/FU Berlin)
The Lunar Laser Communication http://bit.ly/1j7BxDM
Demonstration used a pulsed
laser beam to transmit data
385000 km from the Moon at
a record-breaking download Evidence grows nesium–iron carbonate minerals has
found that it fits the profile of a rock
The hexagon at Saturn’s north pole
was discovered when the Voyager
rate of 622 megabits per second
(Mbps), and achieved an error- for ‘Lake’ Gusev made of ash from explosive volcanic
eruptions in the Gusev region, with
probes flew past the planet in 1980
and 1981; their data indicated that
free upload rate of 20 Mbps from Opinion on whether or not there was carbonate minerals forming later, the clouds within the hexagon were
the ground station in New Mexico. once a lake in Gusev Crater on Mars probably as a result of surface water. moving at around 400 km/hr, similar
http://www.nasa.gov/ladee has ebbed and flowed; now more Steve Ruff, associate research pro- to the jet stream on Earth. Observa-
detailed analysis of rocks thought fessor at Arizona State University, tions since, including six years of
Sentinel in space to have originated in hydrothermal suggests that flood waters came into detailed imagery from the astronomi-
On 3 April, ESA launched activity suggests that they formed the crater through the valley in the cal cameras PlanetCam and Astralux,
Sentinel-1A, the first of its instead from cold water percolating southern rim, and ponded there for on the telescopes of the Calar Alto
Copernicus satellites, part of down from the surface, perhaps as a long enough to alter the volcanic Observatory in Almería, Spain, and
the largest ever civil Earth- result of flood waters intermittently rocks and leave carbonate behind. high-resolution images from the Cas-
observation programme. flooding the lake, then drying out. This new incarnation of Lake Gusev sini spacecraft, show that the hexa-
Sentinel-1A is a radar imager The idea of Lake Gusev arose suggests transient lakes, that do not gon has not varied with the changing
that can operate in varied because the crater topography sug- cover the whole of the crater and are conditions. Saturn’s axial tilt of 27°
modes, providing images of gested a lake, with the southern rim not especially deep. Ruff and team means that its polar atmosphere
natural hazards such as floods, breached by a meandering river sys- published their results in the April undergoes intense seasonal variations
unimpeded by clouds, and can tem. When NASA’s Mars Explora- 2014 issue of Geology. with long polar nights lasting over
assess changes to ice thickness tion Rover, Spirit, landed there in http://bit.ly/1nlaeGa seven years, followed by 23 years of
and vegetation, for example. It search of water-lain sediments, mis- variable illumination.
will also use a synthetic aperture
radar to measure millimetre-
sion scientists found that the crater
floor was made of volcanic rocks. Saturn hexagon Researchers at the Planetary Sci-
ences Group of the UPV/EHU-Uni-
scale changes to topography
that indicate areas of greater
The closest thing to rocks formed
underwater analysed by Spirit’s is stable versity of the Basque Country suggest
that the hexagon and its stream are
seismic hazard. The satellite will instruments were in a region named The hexagonal structure around the the manifestation of a “Rossby
undergo about three months of the Columbia Hills, and these were north pole of Saturn has been stable wave” similar to those that form
commissioning, but has already identified as hydrothermal deposits for 30 years – one Saturn year – and in the mid-latitudes of the Earth.
delivered satisfactory images. – essentially formed in hot springs. its rotation period may be that of Agustín Sánchez-Lavega, Head
http://bit.ly/SwprKB Now reexamination of data from the planet itself, which is otherwise of the Planetary Sciences research
one Columbia Hills rock rich in mag- unknown. group said: “The movement of the
3.8 A&G • June 2014 • Vol. 55
News • Mission Update
hexagon could therefore be linked to
the depths of Saturn, and the rota-
1: The spot at the Space Shorts
outer edge of
tion period of this structure, which,
as we have been able to ascertain, is
Saturn’s A ring in Water from space
this image from
10 hours, 39 minutes and 23 seconds, Techniques developed by the
NASA’s Cassini
could be that of the planet itself.” European Space Agency to
spacecraft could
http://bit.ly/1g5gflg recycle water for astronauts
be an embryo
has been put to use at a school
moon. (NASA/
Cassini finds JPL-Caltech/Space
in Morocco, where groundwater
is undrinkable because it is high
Science Institute)
surprise moon? in nitrates. ESA research has
examined the use of organic
A bright spot in the outermost part and ceramic membranes with
of Saturn’s outermost bright ring (fig- pores just 0.1micron across to
ure 1) may be a moon in the process recycle waste water and urine
of formation, giving researchers an for astronauts and scientists
opportunity to examine how moons in remote situations on Earth.
Downloaded from https://academic.oup.com/astrogeo/article/55/3/ASTROG/239430 by guest on 22 November 2020
develop from Saturn’s rings. Now the University of Kenitra
The object was spotted in Cassini in Morocco, with UNESCO
images taken on 15 April from an arc support, is working with French
about 20% brighter than the region in a reservoir of liquid water under radiation pressures that sweep away and German firms to apply the
of the A ring in which it sits, 1200 km the ice. Now slight fluctuations in the surface particles, could completely technology as a solar and wind-
long and 10 km wide, together with orbital path of the Cassini spacecraft erode small asteroids, with those at powered unit for a school of 1200
unusual structures in the outer edge have been used to assess the density about 28 million miles vanishing in pupils at Sidi Taïbi, 30km from
of the ring, features ascribed to the of the moon at different levels in the about 2 million years. These results Rabat. If it works well, it will be
presence of a nearby large object. subsurface. The gravity anomalies are published in Nature. scaled up to provide water for
“We have not seen anything like suggest liquid water at a depth of http://bit.ly/1myk6zu everyone in the village.
this before,” said Carl Murray of around 30–40 km, most probably http://bit.ly/1jnYhzv
Queen Mary University of London,
lead author of the report in Icarus
extending to a latitude of 50°S. The
observations are published in Science Did LHB trigger Venus’s gravity waves
announcing the find. “We may be
looking at the act of birth, where
by Iess et al.
http://bit.ly/1nlcuxe
plate tectonics? Venus Express has revealed
atmospheric waves propagating
this object is just leaving the rings Evidence of the scale of an impact upwards from the surface of
and heading off to be a moon in its
own right.” Heat variation from the Late Heavy Bombardment
has been found in southern Africa.
the planet to the main cloud
deck and above. Radio data
The possible moon, informally
named Peggy, may be only about creates regolith Not only did it involve devastation
on a world scale, but it may even have
from the Venus Express Radio
Science Experiment (VeRa) have
500 m across – too small to be vis- Temperature cycling and the result- triggered the start of plate tectonics. been confirmed by the Visual
ible – and is probably formed of ant thermal fatigue is responsible for The Barberton greenstone belt in Monitoring Camera, allowing
ice, like Saturn’s moons and rings. the formation of the smaller frac- Southern Africa preserves evidence classification of the wavetrains.
Recent ideas suggest that moons tions of regolith on small asteroids, of an impact 3.26 billion years ago, The waves are more prominent
form from ice particles in the rings, according to experiments carried out within the timeframe of the Late above the area that includes
then move away from the planet, on meteorites on Earth. Heavy Bombardment. Modelling the planet’s highest mountains.
merging with other moons on the Impacts from dust and microscopic based on structures found in the The results strengthen the case
way. In this model, Saturn’s larger fragments of rock arising from aster- greenstone belt led researchers from for topography significantly
moons might have formed from more oid collisions had been assumed to Stanford University to estimate that influencing atmospheric
massive rings; the ring system is now contribute most to the formation the impact – thousands of kilometres circulation on Venus.
depleted, leading to the growth of of the layer of loose, unconsoli- away from these rocks – produced a http://bit.ly/1mIV64f
this much smaller body. It is also dated rock and dust on the surface crater nearly 500 km across, result-
possible that Peggy is in the process of asteroids. But recent laboratory ing in seismic waves larger than any Minisat takes over
of breaking up; Cassini’s orbit will experiments and impact modelling known from an earthquake per- A satellite less than a cubic
move closer to the outer edge of the conducted by a team of French and sisting for half an hour at any one metre in volume has taken over
A ring in late 2016, providing the US researchers have shown that the place, huge tsunamis, the surface of monitoring global plant growth,
chance for a closer look. debris from large impacts reaches the sea boiling, vaporized rock fall- a first for a minisatellite. Proba-V
http://1.usa.gov/1qajpxE escape velocities and breaks free ing as droplets worldwide and dust has been in orbit for a year,
from the gravitational pull of these throughout the atmosphere. correlating the new detectors
Enceladus has asteroids. Instead, their work sug-
gests that thermal fragmentation,
The impact site itself has been
eroded, as has most evidence of these
against those in two existing
SPOT satellites. Proba-V took
subsurface sea induced by mechanical stresses
caused by temperature variations of
large early impacts, but the evidence
of their effects remains. The huge
over from SPOT-5 on 30 May;
SPOT-4 stopped working last
Analysis of the orbit of ESA’s Cassini the rapidly spinning asteroid’s short impactor was between 37 and 58 km year. The new satellite is small
spacecraft as it passed over the south night and day, is the process primar- across and collided with the planet enough to fit into one of the
pole of Saturn’s moon Enceladus has ily responsible for breaking up rocks at 20 km/s, producing a jolt bigger sensors on the van-sized SPOT
confirmed the existence of an ocean larger than a few centimetres across. than a 10.8 magnitude earthquake. satellites. The sensor redesign
of water beneath the moon’s icy crust. Extrapolation of these experiments The impact may have disrupted the maintained the 2250km wide
Anomalies in Saturn’s magneto- also showed that thermal fragmenta- Earth’s crust and the tectonic regime field of view, boosted resolution
sphere drew the attention of the Cas- tion caused rocks to break down an that characterized the early planet, to 100m at best and increased
sini team to Enceladus, leading to the order of magnitude faster than from leading to the start of a more modern memory tenfold. Proba-V is
discovery of plumes of ice and water micrometeoroid impacts, particu- plate tectonic system, according to also able to operate much more
vapour jetting from fissures near the larly at distances comparable to that the paper’s co-authors, Donald Lowe autonomously, avoiding sunlight
moon’s south pole. Further study of of the Earth from the Sun; the speed and Normal Sleep. Their research without human intervention, for
the plumes revealed that they were of breakdown slowed further from will be published in Geochemistry, example.
relatively warm, and salty, both fea- the Sun. Closer to the Sun, thermal Geophysics, Geosystems. http://bit.ly/1mIVhws
tures suggesting that they originate fragmentation, combined with solar http://bit.ly/SwzD5P
A&G • June 2014 • Vol. 55 3.9
Meeting report
RAS Ordinary Meeting
As well as the talks summarized below, the January meeting included the announcement of the Society’s
medals and awards for 2014 (see A&G February 2014 p1.37), followed by Dr Allan Chapman speaking about
a natural ancestor of Sir Patrick Moore: Bishop John Wilkins, born in 1614 (see A&G February 2014 p1.26).
Characterization and implications of intradecadal The Crab Nebula. (NASA,
variations in length of day ESA, J Hester and A Loll
[Arizona State Univ.])
Prof. Richard Models suggest that there is some
Holme, Univer- sign of links between changes in the
sity of Liverpool. LOD and geomagnetic jerks, abrupt
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Variations in changes in the secular acceleration
the rotation of of the geomagnetic field. While
the Earth are these may arise from a jump in the
a powerful but moment of inertia, perhaps arising
overlooked geophysical measure. from a big earthquake, recent large
Decadal variations in the length quakes have been too small by sev-
of day (LOD) arise from angular eral orders of magnitude. Changes
momentum exchange between core at the core–mantle boundary may
and mantle and allow insights into be responsible.
the flow in the Earth’s outer core. http://bit.ly/SE4Tjk
Detection of a noble gas molecule in the Crab Nebula
Prof. Mike Bar- Nebula revealed a very strong line
low, University of unknown origin, later identified
College London. as 36ArH+, the first astronomical
Prof. Barlow detection of a noble gas hydride.
described This species seemed to lie in the
work using bright filaments of the supernova
the Herschel remnant and models suggest that
SPIRE instrument, observing and the Crab is a site for the creation of
36
characterizing dust, in part to Ar from 38Ar and H 2 .
find out if supernovae are sources It may also be a good place to
of dust, especially in the ancient look for HeH+.
A supercomputer model of field lines in Earth’s liquid core. (G Glatzmaier) universe. Observations of the Crab http://bit.ly/1fZnC3b
Icy collisions: the art of planet building behind the snow line Correction
Dr Helen Fraser, experiments involving collisions In the report of the December
Open University. between dust and ice in a vacuum RAS Ordinary (A&G)
Planets form by chamber. The results showed that Meeting (A&G 2014 55 1.9), I
a combination the particles did not stick together mistakenly illustrated Jonathan
of collision and on collision, whether or not ice Betts’s talk with a picture of
aggregation, in was present to act as a glue. While the wrong Harrison clock. In
which ice may the forms of ice used in these addition, the replica clocks are
play a significant role, helping experiments may not replicate those being made by members of the
particles to stick together much like present in space, the message for British Horological Institute
water helps sand grains cohere in those modelling this stage of planet and Mr Betts hopes one will be
sandcastles. Dr Fraser investigated formation was that the coefficients finished in 2015. I apologize for
this for the stage of millimetre– of restitution don’t work as might these errors.
centimetre sized particles, colliding be expected in this situation. Sue Bowler, Editor
with velocities of a few cm s –1, using http://bit.ly/1gbO4Ba Is ice a glue in planet formation? (ESO)
3.10 A&G • June 2014 • Vol. 55Profile: Martin Barstow
Q&A Martin Barstow
What triggered your choice of Who has had the biggest
career? impact on your career?
Growing up in the era of the When I was an undergraduate,
Apollo programme and the Michael Wolfson at the Univer-
Moon landings. There was great sity of York was a great source
optimism about the future of of advice, suggesting I should
space exploration and I wanted go to Leicester for my PhD to
to be part of that future. Patrick work with Ken Pounds. Ken has
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Moore and The Sky at Night were been a fantastic mentor, over
also important in stimulating my several decades. I am pleased to
interest, leading me to join my be following in his footsteps in a
local astronomical society. Later, number of things, including the
when I was studying for A-levels, RAS Presidency.
I realized that a physics degree
could be the key to becoming an What do you hope to achieve
astronomer and space scientist. as RAS President?
It is a tremendous honour to have
What are your interests? been elected by the fellowship.
I have studied white dwarfs and I am very much aware that the
the interstellar medium since I President does not work alone,
was a PhD student. The relatively relying heavily on the support of
recent discovery that white council and the executive. I want
Martin Barstow, President of the RAS, 2014–16
dwarfs appear to be accreting to continue developing the RAS
rocky material from what is left of to be more open, inclusive and
their planetary systems has made the subject, as RAS President universities. When I was Head outward looking, particularly in
this even more interesting. In and Astronomer Royal, and has of Physics and Astronomy at representing the interests of the
parallel, I have also done a lot of contributed across all science as Leicester, I lobbied for a better community to funding agencies
instrument development work for President of the Royal Society and career structure for researchers. and the government. Astronomy
sounding rockets and satellites, now as a member of the House There is more to do, and I didn’t and geophysics research is one of
aimed at getting the observations of Lords. Politically, it is former do it alone, but now at Leicester, the UK’s success stories. How-
I need. Science Minister Lord Sainsbury, someone on a research contract ever, funding is under severe
who in the 1997 Labour govern- has the same opportunity pressure. My main goal is to lead
Where was the most exciting ment presided over an increase in for promotion as anyone in a the RAS in maintaining the excel-
place you’ve worked? funding and much greater recogni- traditional academic position. lence and scope of our disciplines.
For my PhD I worked at White tion of the importance of science. We need to remind everyone that
Sands Missile Range in New What are your current goals? basic “blue skies” science has
Mexico, on a sounding-rocket- What’s your dream job? I have just finished a paper value in its own right and is the
borne telescope, which was a After about 12 years of postdoc (with several colleagues) on UV lynchpin of the supply chain of
precursor to the ROSAT Wide contracts I was lucky to finally observations of hot white dwarfs, scientists and ideas that contrib-
Field Camera. I returned in 2000 land an academic job and I feel which shows that their composi- ute to the economy downstream.
with a new project that developed that I have been incredibly fortu- tions are dominated by accretion I want to develop education and
out of ROSAT. In total, I was nate to progress up the ladder. So, of extrasolar planetary debris. I outreach, to encourage young peo-
involved in six rocket flights from each job has been a dream job, am thinking about the next steps ple into science, and play a role in
there. Unlike satellites, rockets are because I never really expected it! in this area, and looking for new improving the position of women
very hands-on for the scientists. My job now is Head of the Col- UV mission opportunities. We in science. Building on NAM, I
You are much closer to the launch lege of Science and Engineering at have a brilliant instrument (an would like to have a stronger pres-
and have to fit your observations Leicester. I still enjoy research, but EUV spectrograph) developed ence for the RAS outside London.
into a frantic five minutes with no I also enjoy a role that has influ- through our sounding-rocket One thing of particular concern
room for mistakes – a complete ence and can be used to support programme and I would like to is the decline of employment
adrenaline rush! the development of our subject realize the potential of that by opportunities for those complet-
and those working within it. getting it onto a satellite platform. ing PhDs. There is a risk that
Who is the most influential But my main worries are more the pool of more experienced
person you have met? What is your greatest organizational: how do we main- researchers will squeeze out the
In astronomy, Martin Rees. He achievement so far? tain the health of UK astronomy, newly qualified and create a
has contributed to an enormous I always felt it anomalous that geophysics and space science in demographic gap. I don’t have a
range of astronomical problems, research staff were treated this time of increasingly limited solution; suggestions will be most
led the broader development of as second-class citizens in resources? welcome. ●
A&G • June 2014 • Vol. 55 3.11Lahav, Massimi: Standard Model
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1: Will the camera used by
the Dark Energy Survey (see
page 3.15) lead to a paradigm
shift in our understanding of
the universe? (Fermilab)
3.12 A&G • June 2014 • Vol. 55Lahav, Massimi: Standard Model
Dark energy, paradigm shifts,
and the role of evidence
Ofer Lahav and Michela Massimi
examine the current state of the 1: Examples of new entity vs new theory
Standard Model of cosmology phenomenon new entity new theory
in a historical and philosophical
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Uranus’s orbit Neptune (Bessel’s specific gravity ruled
context. out)
Mercury’s orbit (hypothetical planet general relativity
C
osmological measurements, recently Vulcan ruled out)
confirmed and refined by the Planck
beta decay neutrino (violation of angular momentum
space mission and other probes, strongly
ruled out)
favour a “concordance” model, according to
which the universe is flat and contains approxi- galaxy flat rotation curves dark matter? modified Newtonian dynamics?
mately 5% ordinary matter (baryons), 25% cold accelerating universe dark energy? modified general relativity?
dark matter and 70% dark energy (Ade et al. (SN Ia and other data)
2013). The concept of dark energy is a variant
on Einstein’s cosmological constant, lambda
(Λ), and the proposition for a Λ-like linear force p3.15) and other similar projects aim to address 1846. The anomalous perihelion of the planet
can even be traced back to Newton (e.g. Calder this important question by looking for further Uranus had been known for some time. In the
and Lahav 2008, 2010 for a historical perspec- experimental evidence for dark energy. 1820s, the astronomer Friedrich Wilhelm Bessel
tive). This “Λ + cold dark matter” (ΛCDM) There is still the possibility of another major hypothesized a possible departure from New-
paradigm and its extensions pose fundamen- paradigm shift in our understanding of the cos- ton’s inverse square law of gravity to account
tal questions about the origins of the universe. mos, including the following options: for this anomalous perihelion, due to specific
If dark matter and dark energy truly exist, we ● Violation of the Copernican principle: for gravity varying from one body to another. But
must understand their nature. Alternatively, example, if we happen to be living in the mid- the hypothesis was experimentally falsified and
general relativity and related assumptions may dle of a large void. abandoned by the 1840s (Smith 1989). Two
need radical modifications. ● Dark energy being something different than astronomers, Urbain Le Verrier and John Couch
Commonly, dark energy is quantified by an vacuum energy: although vacuum energy is Adams, independently had tried to reconcile this
equation of state parameter, w, which is the mathematically equivalent to Λ, the value pre- piece of negative evidence with Newtonian the-
ratio of pressure to density. The case w = –1 dicted by fundamental theory is as much as ory by postulating the existence of a new planet
corresponds to Einstein’s cosmological con- 10120 times larger than observations permit. called Neptune which, with a certain mass and
stant in general relativity, but in principle w ● Modifications to gravity: it may be that gen- at a certain distance from the orbit of Uranus,
may vary with cosmic epoch, e.g. in the case eral relativity requires revision to a more com- could explain the anomalous perihelion (for
of scalar fields. Essentially, w affects both the plete theory of gravity. historical details, see Grosser 1962). The new
geometry of the universe and the growth rate ● Multiverse: if Λ is large and positive, it would planet was indeed observed on 23 September
of structures. These effects can be observed via have prevented gravity from forming large gal- 1846, the actual position having been predicted
a range of cosmological probes, including the axies, and life would never have emerged. Using with a good degree of accuracy by Adams and
cosmic microwave background (CMB), galaxy this anthropic reasoning to explain the cosmo- Le Verrier. Yet, when Le Verrier applied a simi-
clustering, weak gravitational lensing and Type logical constant problems suggests an infinite lar line of reasoning for the anomalous perihe-
Ia supernovae. The Hubble diagram of Type Ia number of universes (the “multiverse”) in which lion of the planet Mercury, by postulating a new
supernovae (Perlmutter et al. 1999, Riess et al. Λ and other cosmological parameters take on all planet called Vulcan whose mass and orbit could
1998), for which the 2011 Nobel Prize in Phys- possible values. We happen to live in one of the explain the observed anomaly, no such planet
ics was awarded, revealed that our universe is universes that is “habitable”. was observed. Despite early attempts to under-
not only expanding but is also accelerating in stand the 43 arcsec/century of Mercury’s anoma-
its expansion. The main problem is that we still Haven’t we been here before? lous perihelion by modifying Newton’s inverse
have no clue as to what is causing the accelera- While waiting for the results of DES and other square law of gravity (Hall 1894 and Newcomb
tion, or what dark matter and dark energy are. surveys, one can speculate about how the future 1895), a final explanation of the phenomenon
The key point we are addressing in this article of cosmology is going to look. Other cases in came only with the advent of general relativity.
is the following: should a discrepancy between the history of astronomy and physics shed some The episode of Neptune versus Vulcan has
data and the existing cosmological theory be light on our understanding of the current con- been the battleground of important methodo-
resolved by adding new entities such as dark cordance model (see table 1). A famous past epi- logical discussions among philosophers of sci-
matter and dark energy, or by modifying the sode in the history of astronomy is instructive. ence since the early 20th century. Karl Popper
underlying theory? The Dark Energy Survey Consider the discovery of the planet Neptune, famously referred to the discovery of Neptune
(DES; see box “The Dark Energy Survey” predicted by Adams and Le Verrier back in as an attempt by Adams and Le Verrier to
A&G • June 2014 • Vol. 55 3.13You can also read
