Giant galaxy trawl nets astronomers prize

A “uniquely ambitious, far-sighted” project has won an Australian and UK astronomy team the first Group Achievement Award from the UK’s Royal Astronomical Society. The award will be presented today [3 April] at the UK National Astronomy Meeting being held at Queen’s University in Belfast, Northern Ireland.

Led by Professor Matthew Colless (Anglo-Australian Observatory) in Australia and Professor John Peacock (University of Edinburgh) in the UK, the thirty-three-member team spent ten years mapping the distribution in space of 220,000 galaxies using the 3.9-m Anglo-Australian Telescope (AAT) in New South Wales — a project called the 2-degree Field Galaxy Redshift Survey (2dFGRS).

Professors Colless and Peacock will receive the award on behalf of their team.

“The scale of this project made it ground-breaking,” said Matthew Colless. “For the first time we were able to map the positions of a huge number of galaxies and see the subtle effects that reveal the different types of matter in the universe.”

What was needed was for the area of sky surveyed to be much bigger than, rather than the same size as, the “walls” and “strings” of galaxies being detected. Almost ten times larger than any previous survey, the 2dFGRS was the first study to meet this crucial condition.

The survey measured patterns in the distribution of galaxies, on scales from 100 million to 1 billion light-years. Two wedge-shaped pieces of sky were surveyed, so when the galaxies within them were mapped out, the result looked like a bow-tie cut from a sponge: a network of voids and dense regions.

Key results from the 2dFGRS were:

  • the first accurate ratio of the amount of normal ("baryonic") matter to the unseen "dark" matter in the Universe;
  • confirmation that today's galaxies grew from tiny quantum density fluctuations in the early Universe by positive feedback, whereby dense structures grow and become more massive by attracting yet more matter;
  • confirmation that the Universe does not have enough matter for gravity to rein in its expansion; and 
  • the tightest constraint to that time on the mass of the neutrino.

Seven members of the 2dFGRS team [listed below] are currently based at Australian institutions: the Anglo-Australian Observatory (which operates the Anglo-Australian Telescope) in Sydney, the University of Sydney, Swinburne University of Technology in Melbourne, the Australian National University in Canberra, and CSIRO’s Australia Telescope National Facility in Sydney.

The size of the 2dF Galaxy Redshift Survey was made possible only by technological advances developed at the Anglo-Australian Observatory (AAO). The 2dF spectrograph used robotic technology to place optical fibres onto the telescope’s focal plane, where each fibre could collect the light from a single galaxy. By using up to 400 optical fibres, this system allowed the light from up to 400 galaxies to be captured simultaneously.

The AAO has continued to develop this technology. It has exported an advanced optical fibre robot, called Echidna, to Japan’s 8.2-m Subaru telescope in Hawai’i, and in February this year the AAO and partner institutions were contracted by the international Gemini Observatory to carry out one of two competing design studies for an instrument with more than 4000 fibres, the Wide-field Fiber Multi-Object Spectrograph (WFMOS). Key WFMOS projects will be to uncover the history of our Galaxy and probe the nature of Dark Energy.

In addition to designing and building instruments for other telescopes, the AAO is continuing to do excellent science with its own 3.9-m Anglo-Australian Telescope (AAT) in Australia. Since 2006 the telescope has been equipped with AAOmega, which is arguably the world's best wide-field spectroscopic survey facility, and which will be surpassed only by WFMOS itself.

The AAO plans to continue to operate the AAT with the support of the Australian Government past 2010, when, because of the UK’s phased withdrawal, the Observatory will become a wholly Australian entity.


2dFGRS team members at Australian institutions

Professor Matthew Colless
Anglo-Australian Observatory
Currently in the UK. Contact through NAM press room (until 4 April):
+44 02890 975 262 (also -263 and -264)
Press officers:
Dr Robert Massey. Mob: +44 0794 124 8035
Ms Anita Heward. Mob: +44 0775 603 4243

Dr Joss Bland-Hawthorn
University of Sydney
02 9351 2621

Dr Russell Cannon
Anglo-Australian Observatory
02 9876 8117

Professor Warrick Couch
Swinburne University
Currently in the UK. Contact through NAM press room (until 4 April): details above.

Professor Karl Glazebrook
Swinburne University
03 9214 4384

Dr Carole Jackson
CSIRO Australia Telescope National Facility
Mob. 0432 925 932

Dr Bruce Peterson
The Australian National University
02 6125 8035



The galaxy map produced by the 2dF Galaxy Redshift Survey. Each dot represents a galaxy: Earth, and our own Galaxy, is at the centre of the “bow-tie”. The colour coding indicates how tightly the galaxies are clustered, with red being the most highly clustered regions.[205 KB]
Image credit: Paul Bourke, University of Western Australia

One half of the 2dFGRS galaxy map, showing more clearly the “spongy” pattern of the galaxy distribution. The colours indicate how tightly the galaxies are clustered, with red areas being the most highly clustered regions.[294 KB]
Image credit: Paul Bourke, University of Western Australia

A schematic illustration (not to scale), showing our Galaxy and the positions of the two “wedges” of space that were surveyed for the 2dF Galaxy Redshift Survey.[58 KB]
Image credit: 2dFGRS team

The 2dF instrument mounted on the Anglo-Australian Telescope. [1.3 MB]
Credit: Anglo-Australian Observatory

The Anglo-Australian Telescope (foreground) at Siding Spring Observatory in central New South Wales. [2.7 MB]
Photo: David Malin

Media assistance: Helen Sim 
+61-(0)2-9372-4251 (office)
+61-(0)419-635-905 (mob.)