M-42 Continued
The Orion Nebula is believed to be a huge star formation region about 1630 light years away. The bright part of the nebula is the glow of many luminous, newborn stars shining on the surrounding gas cloud that they collapsed from. The stars that are being born in the Orion Nebula are part of what astronomers call an "open cluster." When all of the stars are done being born, what will remain is a clump of a few hundred to a thousand stars which are all roughly the same age (give or take a few tens of millions of years!). A few very massive, very bright stars called the Trapezium dominate these stellar siblings. The Trapezium is made up of just a few stars, but it outshines all the rest of them combined. Astronomers believe that the majority of the glow from the gas in the nebula comes from light from the stars of the Trapezium.