Eta Carinae Nebula (NGC 3372)
A large cloud of ionized hydrogen (H II region) in the southern Milky Way in the constellation Carina. The star Eta Carinae is embedded in it, near its centre.
The nebula has an apparent diameter of 3°, corresponding to a real size of 400 light years at a distance of 7,500 light years, making it much larger than the Orion Nebula. It is a region of star formation containing a number of young star clusters.

See also: Keyhole Nebula.