Horsehead and Flame

Not too far from the famous Orion Nebula and situated around the star Alnitak, the leftmost of the three stars making up the belt of Orion is an ensemble of bright and dark nebulae. It contains the well-known horsehead nebula, which is a dark dust cloud in front of an extended HII emission nebula… and the dust cloud happens to resemble the head of a horse on the backdrop of the bright Ha emission. Part of the ensemble is also the flame nebula, another dramatic combination of dark and bright nebulosity. To top-off the scenery, there are a couple of blue reflection nebulae scattered around bright hot stars. In the middle of it all is Alnitak, a hot blue supergiant with an effective surface temperature of 25000 K and magnitude 2.

The color image above is composed of 230 individual luminance and RGB images of 2 minutes exposure time, making more than 7 hours total integration time. The colors are realistic, although the color saturation is enhanced.