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]

okt 182012
 
Giant Impacts Explain the Unusual Moons of Saturn

  Among the oddities of the outer Solar System are the middle-sized moons of Saturn, a half-dozen icy bodies dwarfed by Saturn’s massive moon Titan. According to a new model for the origin of the Saturn system, these middle-sized moons were spawned during giant impacts in which several major satellites merged to form Titan. Saturn’s [continue reading]

okt 172012
 
Massive Galaxies See Big Meals and Snacks in Other Galaxies

  Gravity Lenses Suggest Big Collisions Make Galaxies Denser   Using gravitational “lenses” in space, University of Utah astronomers discovered that the centers of the biggest galaxies are growing denser – evidence of repeated collisions and mergers by massive galaxies with 100 billion stars. This image, taken by the Hubble Space Telescope, shows a ring [continue reading]

okt 092012
 
Cosmic Blender Churns Galaxy Cluster

  Scientists have used a suite of X-ray observations to find evidence of large scale swirling gas motion in the Perseus galaxy cluster. The Perseus Cluster, located 237 million light-years away in the constellation of Perseus, contains thousands of galaxies immersed in a vast cloud of multimillion degree gas. Image Credit: Jean-Charles Cuillandre (CFHT) & Giovanni [continue reading]

sep 182012
 
The Dying Tones of Colliding Black Holes

  Researchers from Cardiff University have discovered a new property of black holes: their dying tones could reveal the cosmic crash that produced them. Black holes are regions of space where gravity is so strong that not even light can escape and so isolated black holes are truly dark objects and don’t emit any form of radiation. [continue reading]

aug 162012
 
Star Clusters in the Tarantula Nebula on a Collision Course

  Astronomers using data from NASA’s Hubble Space Telescope have caught two clusters full of massive stars that may be in the early stages of merging. The clusters are 170,000 light-years away in the Large Magellanic Cloud, a small satellite galaxy to our Milky Way. This is a Hubble Space Telescope image of a pair [continue reading]