Shedding Light on the Cosmic Skeleton

NASA Astrophysics Data System (ADS)

2009-11-01

, and have identified several groups of galaxies surrounding the main galaxy cluster. They could distinguish tens of such clumps, each typically ten times as massive as our own Milky Way galaxy - and some as much as a thousand times more massive - while they estimate that the mass of the cluster amounts to at least ten thousand times the mass of the Milky Way. Some of the clumps are feeling the fatal gravitational pull of the cluster, and will eventually fall into it. "This is the first time that we have observed such a rich and prominent structure in the distant Universe," says Tanaka. "We can now move from demography to sociology and study how the properties of galaxies depend on their environment, at a time when the Universe was only two thirds of its present age." The filament is located about 6.7 billion light-years away from us and extends over at least 60 million light-years. The newly uncovered structure does probably extend further, beyond the field probed by the team, and hence future observations have already been planned to obtain a definite measure of its size. More information This research was presented in a paper published as a letter in the Astronomy & Astrophysics Journal: The spectroscopically confirmed huge cosmic structure at z = 0.55, by Tanaka et al. The team is composed of Masayuki Tanaka (ESO), Alexis Finoguenov (Max-Planck-Institute for Extraterrestrial Physics, Garching, Germany and University of Maryland, Baltimore, USA), Tadayuki Kodama (National Astronomical Observatory of Japan, Tokyo, Japan), Yusei Koyama (Department of Astronomy, University of Tokyo, Japan), Ben Maughan (H.H. Wills Physics Laboratory, University of Bristol, UK) and Fumiaki Nakata (Subaru Telescope, National Astronomical Observatory of Japan). ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech