Emission nebula NGC 3576, X-ray image. Emission nebulae are clouds of gas and dust that emit light as they are ionised by radiation from the young stars inside them. Some stars in this image of NGC 3576 have been revealed for the first time, as the nebula is so dense they are normally hidden by it. In the most dense regions, embryonic stars are formed (blue), which grow as they accumulate gas and dust from their surroundings. The nebula is sculptured by strong stellar winds emerging from the hot cluster of stars at its core. NGC 3576 is around 9000 light years away from Earth in the constellation Carina. Image taken by NASA's Chandra telescope on 21st and 23rd July 2005.