okt 082012
Twists and Turns in Interacting Galaxies

  Almost thirty years ago the Infrared Astronomy Satellite, IRAS, discovered that the Universe contained many fabulously luminous galaxies, some of them more than a thousand times brighter than our own galaxy, but which are practically invisible at optical wavelengths. The reason for their optical dimness is that their bright light comes not from stars, [continue reading]