The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated south of Orion's Belt in the constellation of Orion. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of 1,344 ± 20 light years and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. It has a mass of about 2000 times the mass of the Sun. Older texts frequently refer to the Orion Nebula as the Great Nebula in Orion or the Great Orion Nebula.It is the most viewed and photographed deep celestial object and we are considered part of its neighborhood as it is on the same spiral arm as we are.The picture below shows the location of M42, the Orion Nebula in the constellation Orion. It is the middle of three points of light near Orion's sword.
This image was produced from a screen shot from Stellarium, and edited in Gimp by Barry Nelson.
The Orion Nebula is one of the most scrutinized and photographed objects in the night sky, and is among the most intensely studied celestial features.The nebula has revealed much about the process of how stars and planetary systems are formed from collapsing clouds of gas and dust. Astronomers have directly observed protoplanetary disks, brown dwarfs, intense and turbulent motions of the gas, and the photo-ionizing effects of massive nearby stars in the nebula. There are also supersonic "bullets" of gas piercing the hydrogen clouds of the Orion Nebula. Each bullet is ten times the diameter of Pluto's orbit and tipped with iron atoms glowing bright blue. They were probably formed one thousand years ago from an unknown violent event.
This nebula is quite easy to find as its brightness makes it easily visible to the naked eye even in light polluted areas thus requiring no star hopping. Orion's belt is one of the most distinct star formations in the night sky and so should be located first. Once found, look for a dimmer group of stars just to the south of the belt. In the mid section of this group (Orion's sword) is the nebula.
The Great Nebula; a wonderful object, easily visible to the naked eye in fairly dark skies. In the midst of the nebula is the Trapezium, whose four bright stars are easily seen.
The nebula is best viewed once one's eyes are well accustomed to the dark and using averted vision will also help to bring out some of the more subtle details.