M42 Orion Nebula

Messier 42 occupies an area of 65 by 60 arc minutes of apparent sky and its spatial diameter measures 24 light years. The nebula has a mass 2,000 times that of the Sun and contains associations of stars, reflection nebulae, neutral clouds of dust and gas, and ionized gas. It is part of the Orion Molecular Cloud Complex, a larger region of nebulosity that also includes the famous Horsehead Nebula, the Flame Nebula, the emission nebula Barnard’s Loop, De Mairan’s Nebula (M43), and the reflection nebula Messier 78.

The Orion Molecular Cloud Complex covers an area of more than 10 degrees, which is more than half of Orion constellation.

The Orion Nebula is a place of massive star formation and one of the most studied deep sky objects in our vicinity as it allows astronomers to study the process of stars forming from clouds of dust and gas and the photo-ionizing effects of massive young stars that are responsible for the nebula’s glow. New stars are forming throughout the nebula. The temperature in the central region is up to 10,000 K and considerably lower around the edges.