M42 - The Orion Nebula
Copyright: Ryan Steinberg and Family/Adam Block/NOAO/AURA/NSF
The Orion Nebula is a spectacular region of star formation within our own galaxy, some 1600 light-years away. With the rest of the Orion constellation it is visible from almost all latitudes during Northern hemisphere winters (Southern hemisphere summers). The nebula itself is visible to the naked eye under dark skies as a small patch below Orion's belt. Binoculars show some of the structure of the nebula and may even give a greenish appearance. As the photograph shows, the true colour is reddish, but the human eye has poor sensitivity to colour at low intensities and registers green wavelengths more than red in this situation.