Carina nebula (NGC 3372), optical image. This is an emission nebula, a huge cloud of gas and dust that glows as the hydrogen it contains is ionised by radiation from the hot young stars that have formed within it. It lies between 6,500 and 10,000 light years from Earth in the constellation of Carina. Within the nebula is the hypergiant star Eta Carinae, one of the brightest stars in the Milky Way.