August 1, 2012
VLT Finds Tranquil Blue Galaxy Is Home To Violent Events
April Flowers for redOrbit.com - Your Universe Online
About 60 million light-years away, there is a beautiful, tranquil looking blue spiral galaxy named NGC 1187. This galaxy is in the constellation of Eridanus, or The River.
NGC 1187 has about half a dozen prominent spiral arms, filled with large amounts of gas and dust. The arms appear blue, which indicates the presence of young stars recently born from the clouds of interstellar gas. The center of this galaxy has a glowing yellow bulge in the subtle shape of a bar. Central bar features are thought to act as channel mechanisms to move gas from the spiral arms to the center, enhancing star formation.
Much fainter and more distant galaxies can be seen, their reddish hued clusters shining through the disc of NGC 1187.
NGC 1187 is of interest because, no matter how peaceful and unchanging it appears, two supernovae events have been recorded in the galaxy in the last 30 years. Supernovae are violent stellar explosions. These can result from either the death of a massive star or a white dwarf in a binary system. A supernova emits such strong energy they frequently outshine the entire galaxy for a short time before fading from view. During this time of immense output, the supernova can release more energy than the Sun will in its entire life span.
SN 1982R was the first supernova observed in NGC 1187 by the astronomers at ESO's La Silla Observatory. An amateur astronomer in South Africa, Berto Monard, spotted the second supernova, SN 2007Y. A research team then monitored and performed a detailed study of SN 2007Y for about a year using many different telescopes. SN 2007Y can still be seen near the bottom of the galaxy.