The picture is dominated by a large, approximately circular feature, about 7 light-years across, which is part of the Keyhole Nebula, named in the 19th century by British astronomer Sir John Herschel. This region, about 8000 light-years from Earth, is located near to the famous explosive variable star Eta Carinae, which lies just outside the field of view toward the upper right.
The Carina Nebula also contains several other stars that are among the hottest and most massive known, each about 10 times as hot, and 100 times as massive, as our Sun.
The circular 'keyhole' structure contains both bright filaments of hot gas and dark silhouetted clouds of cold molecules and dust, all of which are in rapid, chaotic motion. Two striking large, sharp-edged dust clouds are located near the bottom centre and upper-left edges of the image. These large dark clouds may eventually evaporate or, if there are sufficiently dense condensations within them, give birth to small star clusters.
The Carina Nebula, with an overall diameter of more than 200 light-years, is one of the outstanding features of the southern-hemisphere part of the Milky Way.