Saturday, August 29, 2009
Gum Nebula(Gum 12) is a round, large nebula. It is so large, yet hardly visible against a bright and complex background; its front edge is as close to us as 450 light-years, while its back edge lies about 1,500 light-years away.
The Gum Nebula is believed to be the hugely expanded remains of a supernova that took place around a million years ago. It contains the Vela OB2 Association, the hot stars of which cause it to shine. Also embedded in the Gum are the Vela Supernova Remnant and the Vela Pulsar.
It is named after its discoverer, the Australian astronomer Colin Stanley Gum, who published his findings in 1955.