mrt 052013
Anne's Picture of the Day: Interacting Galaxies Arp 299

March 5, 2013 Arp 299, interacting galaxies in Ursa Major Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University) Arp 299, consisting of IC 694 (left) and NGC 3690 (right), is an interacting pair of barred irregular galaxies that lie about 134 million light-years away in [continue reading]

sep 172012
Supernovae Now Counted

  Almost one in five exploding stars in nearby galaxies is simply not seen, astronomers have determined. For galaxies further out, that fraction doubles. This finding clears the way for these stellar beacons to be used as a good measure of how fast galaxies made stars earlier in the Universe’s history. Key evidence for this “body count” [continue reading]