ESO image of the nebula AB7. AB7 is a binary star system found in one of the nearby Magellanic Cloud galaxies, consisting of one WR-star - highly evolved massive star - and a mid-age massive companion of spectral type O. These exceptional stars have very strong stellar winds : they continuously eject energetic particles some 10 to 1,000 million times more intensely than our sun. The surface temperature is in excess of 120,000 degrees, maybe the universe's hottest star.
The famous Horsehead Nebula is about 1,500 light-years from Earth, in the constellation Orion. The nebula is located just to the south of the star Alnitak, which is farthest east on Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex.: