Massive black holes 'switched on' by galaxy collision
Tuesday, June 15, 2010 - 15:50
in Astronomy & Space
(PhysOrg.com) -- The centre of most galaxies harbours a massive black hole. Our Milky Way galaxy is one of these - the exotic object there however is reasonably calm, unlike some super-massive gravity monsters in other galaxies. Scientists at the Max Planck Institute for Extraterrestrial Physics and other institutions around the world have now analysed 199 of these galaxies and discovered what makes the black holes at the galaxy centres become active: The black holes were "switched on" some 700 million years ago after major galaxy merger events. (The Astrophysical Journal, in press)