Glowing clouds of gas and dust surround the three stars of Orion's Belt in this long-exposure photograph of the region. From left, the stars of the belt are Alnitak, Alnilam, and Mintaka. All three are supergiant stars that will explode as supernovae. The nebulosity around the stars includes the Horsehead Nebula, a dark notch in the red cloud close to the lower left of Alnitak. [Rogelio Bernal Andreo/Wikimedia] [2]