The Orion Nebula (M42) is the closest stellar nursery to our solar system.
Stellar nurseries are special regions where the vast majority of new stars in the
galaxy are born. Interstellar clouds of molecular gas form, produce thousands of
new stars and then gradually dissipate. The Orion Nebula is 1,500 light years from
Earth and six light years or 35 trillion miles across. It forms the second point of
light in the hunter’s sword in the Orion constellation.
The following images of the Orion constellation show emissions nebulae
M42 and M43, and the Running Man reflection nebula NGC 1977, the first point
of light in the sword. Emission nebulae radiate a reddish glow that comes from hot
ionized gas. Reflection nebulae, as the name implies, reflect starlight rather than
giving off their own radiation and have a bluish cast because their interstellar dust
grains preferentially reflect blue light. These bright nebulae are actually the
brightest parts of a huge cloud of interstellar gas and dust which is several hundred
light years across.
released August 18, 2012