jan 262013
Anne's Picture of the Day: Galaxy Cluster Abell 2218

January 26, 2013 Abell 2218, a galaxy cluster in Draco Image Credit: NASA, ESA, and Johan Richard (Caltech, USA) Acknowledgement: Davide de Martin & James Long (ESA/Hubble) Abell 2218 is a rich galaxy cluster that contains more than 10,000 galaxies, located some 2.35 billion light-years away (redshift 0.18) in the northern constellation of Draco. Redshift [continue reading]

jan 202013
No Galaxy Is An Island, Entire of Itself

  KIPAC scientists use X-ray observations show how galaxies shape their environment, and vice-versa   A major component of our understanding of galaxy evolution that has remained elusive is the influence of the local environment on the galaxy, especially when discussing galaxies in large clusters. Galaxy clusters, the largest gravitationally bound objects in the Universe, [continue reading]

jan 132013
Anne's Picture of the Day: The Train Wreck Cluster

January 13, 2013 The Train Wreck Cluster, a galaxy cluster in Orion Image Credit: NASA, ESA, CFHT, and M.J. Jee (University of California, Davis) The Train Wreck Cluster (Abell 520) is a galaxy cluster of 5.4 million light-years across that contains about 300 galaxies. It lies some 2.65 billion light-years away in the constellation of [continue reading]

dec 252012
Anne's Picture of the Day: Galaxy Cluster CLG J02182-05102

December 25, 2012 CLG J02182-05102, an ancient galaxy cluster in Cetus Image Credit: NASA/JPL-Caltech/Subaru CLG J02182-05102 (also known as SXDF-XCLJ0218-0510) is a galaxy cluster that contains some 60 galaxies, located about 9.6 billion light-years away in the constellation of Cetus. For comparison, the much younger Local Group of which the Milky is a member, contains [continue reading]

dec 012012
‘Dark Core’ in Galaxy Cluster May Not Be So Dark After All

  Astronomers were puzzled earlier this year when NASA’s Hubble Space Telescope spotted an overabundance of dark matter in the heart of the merging galaxy cluster Abell 520. This observation was surprising because dark matter and galaxies should be anchored together, even during a collision between galaxy clusters. These composite images taken by two different [continue reading]