Caption: Unlike the Sun, many stars are found in rich clusters such as NGC 3293 where they spend their lives. At the time of their formation, the brightest stars in the cluster were hot, and therefore blue, but such stars quickly deplete their supplies of nuclear fuel. This evolutionary process involves cooling, so that the stars become redder, but paradoxically they also brighten because they swell to an enormous size. The bright orange star in NGC 3293 is the member of the group that has aged fastest and is likely to be the next supernova in the cluster, which is in the constellation of Carina at a distance of about 8,500 light years.
Copyright: (c) 1977 Anglo-Australian Telescope Board, photograph by David Malin