Prawn Nebula or IC 4628 is an emission nebula located around 6000 light-years from Earth, south of the star Antares, in the tail of the nebula-rich constellation Scorpius (The Scorpion). The Prawn Nebula was discovered by the American astronomer Edward Emerson Barnard around 1900. The nebula is also cataloged as Gum 56 for Australian astronomer Colin Stanley Gum.
IC 4628 has an apparent magnitude of 7.31, with a stellar nursery that contains a large number of very hot, luminous, young stars, formed out of the surrounding gas. These stars include two large, hot, blue-white giants belonging to the rare spectral class O. O-type stars have a relatively short life span as they tend to burn out very quickly before ending their lives in supernova explosions and collapsing into either neutron stars or black holes. The blue giants in IC 4628 will end their lives after only about a million years. The material produced by their supernova explosions will be used to form new stars in the nebula. The two luminous giants and other young stars in the nebula are responsible for illuminating the surrounding gas. The stars emit an enormous amount of ultraviolet radiation which ionises the hydrogen gas in the nebula, making it glow, dominated by the red emission of hydrogen. The region shown is about 250 light-years across, spanning an area equivalent to four full moons.
Credits: Astronomy, NASA, Space.