Galaxy images from the GAMA survey
GAMA survey releases first data at IAU General Assembly
An international team of astronomers studying more than 200 000 galaxies has measured the energy generated within a large portion of space more precisely than ever before. This represents the most comprehensive assessment of the energy output of the nearby Universe. They confirm that the energy produced in a section of the Universe today is only about half what it was two billion years ago and find that this fading is occurring across all wavelengths from the ultraviolet to the far infrared. The Universe is slowly dying.
The study involves many of the world’s most powerful telescopes, including ESO's VISTA and VST
survey telescopes at the Paranal Observatory in Chile. Supporting
observations were made by two orbiting space telescopes operated by NASA
(GALEX and WISE) and another belonging to the European Space Agency (Herschel) [1].
The research is part of the Galaxy And Mass Assembly (GAMA) project, the largest multi-wavelength survey ever put together.
“We used as many space and ground-based telescopes as we could
get our hands on to measure the energy output of over 200 000 galaxies
across as broad a wavelength range as possible,” says Simon Driver (ICRAR, The University of Western Australia), who heads the large GAMA team.
The survey data, released to astronomers around the world today,
includes measurements of the energy output of each galaxy at 21
wavelengths, from the ultraviolet to the far infrared. This dataset will
help scientists to better understand how different types of galaxies
form and evolve.
All the energy in the Universe was created in the Big Bang, with some
portion locked up as mass. Stars shine by converting mass back into
energy, as described by Einstein’s famous equation E=mc2 [2].
The GAMA study sets out to map and model all of the energy generated
within a large volume of space today and at different times in the past.
“While most of the energy sloshing around in the Universe arose
in the aftermath of the Big Bang, additional energy is constantly being
generated by stars as they fuse elements like hydrogen and helium
together,” Simon Driver says. “This new energy is either
absorbed by dust as it travels through the host galaxy, or escapes into
intergalactic space and travels until it hits something, such as another
star, a planet, or, very occasionally, a telescope mirror.”
The fact that the Universe is slowly fading has been known since the
late 1990s, but this work shows that it is happening across all
wavelengths from the ultraviolet to the infrared, representing the most
comprehensive assessment of the energy output of the nearby Universe.
"The Universe will decline from here on in, sliding gently into
old age. The Universe has basically sat down on the sofa, pulled up a
blanket and is about to nod off for an eternal doze,” concludes Simon Driver.
The team of researchers hope to expand the work to map energy
production over the entire history of the Universe, using a swathe of
new facilities, including the world’s largest radio telescope, the Square Kilometre Array, which is due to be built in Australia and South Africa over the next decade.
The team will present this work at the International Astronomical Union XXIX General Assembly in Honolulu, Hawaii, on Monday 10 August 2015.
Notes
[1] The telescopes and survey data used, in order of increasing wavelength, were: GALEX, SDSS, VST (KiDS survey), AAT, VISTA (VIKING survey)/UKIRT, WISE, Herschel (PACS/SPIRE).
[2] Much of the Universe’s energy output comes from nuclear fusion in stars, when mass is slowly converted into energy. Another major source is the very hot discs around black holes at the centres of galaxies, where gravitational energy is converted to electromagnetic radiation in quasars and other active galactic nuclei. Much longer wavelength radiation comes from huge dust clouds that are re-radiating the energy from stars within them.
More Information
This research will be presented in a paper entitled “Galaxy And Mass
Assembly (GAMA): Panchromatic Data Release (far-UV—far-IR) and the low-z
energy budget”, by S. Driver et al., submitted to the journal Monthly Notices of the Royal Astronomical Society. It will also be the subject of a talk and press event at the IAU General Assembly in Hawaii on 10 August 2015.
The team is composed of Simon P. Driver (ICRAR, The University of
Western Australia, Crawley, Western Australia, Australia [ICRAR];
University of St Andrews, United Kingdom), Angus H. Wright (ICRAR),
Stephen K. Andrews (ICRAR), Luke J. Davies (ICRAR) , Prajwal R. Kafle
(ICRAR), Rebecca Lange (ICRAR), Amanda J. Moffett (ICRAR) , Elizabeth
Mannering (ICRAR), Aaron S. G. Robotham (ICRAR), Kevin Vinsen (ICRAR),
Mehmet Alpaslan (NASA Ames Research Centre, Mountain View, California,
United States), Ellen Andrae (Max Planck Institute for Nuclear Physics,
Heidelberg, Germany [MPIK]), Ivan K. Baldry (Liverpool John Moores
University, Liverpool, United Kingdom), Amanda E. Bauer (Australian
Astronomical Observatory, North Ryde, NSW, Australia [AAO]), Steve
Bamford (University of Nottingham, United Kingdom), Joss Bland-Hawthorn
(University of Sydney, NSW, Australia), Nathan Bourne (Institute for
Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, United
Kingdom), Sarah Brough (AAO), Michael J. I. Brown (Monash University,
Clayton, Victoria, Australia), Michelle E. Cluver (The University of
Western Cape, Bellville, South Africa), Scott Croom (University of
Sydney, NSW, Australia), Matthew Colless (Australian National
University, Canberra, ACT, Australia), Christopher J. Conselice
(University of Nottingham, United Kingdom), Elisabete da Cunha
(Macquarie University, Sydney NSW, Australia), Roberto De Propris
(University of Turku, Piikkiö, Finland), Michael Drinkwater (Queensland
University of Technology, Brisbane, Queensland, Australia), Loretta
Dunne (Institute for Astronomy, University of Edinburgh, Royal
Observatory, Edinburgh, United Kingdom; Cardiff University, Cardiff,
United Kingdom), Steve Eales (Cardiff University, Cardiff, United
Kingdom), Alastair Edge (Durham University, Durham, United Kingdom),
Carlos Frenk (Durham University, Durham, United Kingdom), Alister W.
Graham (Macquarie University, Sydney NSW, Australia), Meiert Grootes
(MPIK), Benne W. Holwerda (Leiden Observatory, University of Leiden,
Leiden, The Netherlands), Andrew M. Hopkins (AAO) , Edo Ibar
(Universidad de Valparaso, Valparaiso, Chile), Eelco van Kampen (ESO,
Garching, Germany), Lee S. Kelvin (Liverpool John Moores University,
Liverpool, United Kingdom), Tom Jarrett (University of Cape Town,
Rondebosch, South Africa), D. Heath Jones (Macquarie University, Sydney,
NSW, Australia), Maritza A. Lara-Lopez (Universidad Nacional Automana
de México, México), Angel R. Lopez-Sanchez (AAO), Joe Liske (Hamburger
Sternwarte, Universität Hamburg, Hamburg, Germany), Jon Loveday
(University of Sussex, Falmer, Brighton, United Kingdom), Steve J.
Maddox (Institute for Astronomy, University of Edinburgh, Royal
Observatory, Edinburgh, United Kingdom; Cardiff University, Cardiff,
United Kingdom), Barry Madore (Observatories of the Carnegie Institution
of Washington, Pasadena, California, United States [OCIW]), Martin
Meyer (ICRAR) , Peder Norberg (Durham University, Durham, United
Kingdom), Samantha J. Penny (University of Portsmouth, Portsmouth,
United Kingdom), Stephen Phillipps (University of Bristol, Bristol,
United Kingdom), Cristina Popescu (University of Central Lancashire,
Preston, Lancashire), Richard J. Tuffs (MPIK), John A. Peacock
(Institute for Astronomy, University of Edinburgh, Royal Observatory,
Edinburgh, United Kingdom), Kevin A.Pimbblet (Monash University,
Clayton, Victoria, Australia; University of Hull, Hull, United Kingdom),
Kate Rowlands (University of St Andrews, United Kingdom), Anne E.
Sansom (University of Central Lancashire, Preston, Lancashire), Mark
Seibert (OCIW), Matthew W.L. Smith (Queensland University of Technology,
Brisbane, Queensland, Australia), Will J. Sutherland (Queen Mary
University London, London, United Kingdom), Edward N. Taylor (The
University of Melbourne, Parkville, Victoria, Australia), Elisabetta
Valiante (Cardiff University, Cardiff, United Kingdom), Lingyu Wang
(Durham University, Durham, United Kingdom; SRON Netherlands Institute
for Space Research, Groningen, The Netherlands), Stephen M. Wilkins
(University of Sussex, Falmer, Brighton, United Kingdom) and Richard
Williams (Liverpool John Moores University, Liverpool, United Kingdom).
The Galaxy and Mass Assembly Survey, or GAMA, is a collaboration
involving nearly 100 scientists from more than 30 universities located
in Australia, Europe and the United States.
ICRAR is a joint venture between Curtin University and The University
of Western Australia with support and funding from the State Government
of Western Australia.
ESO is the foremost intergovernmental astronomy organisation in
Europe and the world’s most productive ground-based astronomical
observatory by far. It is supported by 16 countries: Austria, Belgium,
Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy,
the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the
United Kingdom, along with the host state of Chile. ESO carries out an
ambitious programme focused on the design, construction and operation of
powerful ground-based observing facilities enabling astronomers to make
important scientific discoveries. ESO also plays a leading role in
promoting and organising cooperation in astronomical research. ESO
operates three unique world-class observing sites in Chile: La Silla,
Paranal and Chajnantor. At Paranal, ESO operates the Very Large
Telescope, the world’s most advanced visible-light astronomical
observatory and two survey telescopes. VISTA works in the infrared and
is the world’s largest survey telescope and the VLT Survey Telescope is
the largest telescope designed to exclusively survey the skies in
visible light. ESO is a major partner in ALMA, the largest astronomical
project in existence. And on Cerro Armazones, close to Paranal, ESO is
building the 39-metre European Extremely Large Telescope, the E-ELT,
which will become “the world’s biggest eye on the sky”.
Links
Contacts
ICRAR – University of Western Australia
Tel: +61 400 713 514
Cell: +1 808 304 2392
Email: simon.driver@icrar.org
Andrew Hopkins
Australian Astronomical Observatory
North Ryde, NSW, Australia
Tel: +61 432 855 049
Email: andrew.hopkins@aao.gov.au
Joe Liske
Hamburger Sternwarte, Universität Hamburg
Hamburg, Germany
Email: jochen.liske@uni-hamburg.de
Pete Wheeler
Media Contact. ICRAR – University of Western Australia
Australia
Tel: +61 423 982 018
Email: pete.wheeler@icrar.org
Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org
Source: ESO
