The Orion molecular cloud is a large complex of hot young stars, nebulae, and dark clouds of gas and dust located in the constellation of Orion. Two particularly famous sights in the night sky, the Orion Nebula and the Horsehead Nebula, are members of this complex, which is relatively nearby, only about 1500 light-years away. Despite its fame, brightness, and relative proximity, however, this complex is not very well understood. Take its star formation, for instance. The relative roles of the local versus galactic-wide conditions are poorly modeled, in particular the contributions of small-scale processes like magnetic fields and turbulence as compared to larger scale activity like gas pressure or the streaming motions of gas within the galaxy’s spiral arms. One reason for this lack of understanding is that the nebula is densely packed with stars and activity while its dust obscures many of the regions from optical view.
The anatomy of Orion