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Molecular Cloud

A dense and cold region of interstellar space composed primarily of molecular hydrogen, serving as the birthplace of stars. The molecular cloud associated with NGC 346 is actively forming new stars.

Source: science.nasa.gov

APODs including "Molecular Cloud"

M43: Streams of Orion

06/10/2021

M43: Streams of Orion
Image Credit: Jari Saukkonen / NASA APOD

Where do the dark streams of dust in the Orion Nebula originate? This part of the Orion Molecular Cloud Complex, M43, is the often imaged but rarely mentioned neighbor of the more famous M42. M42, seen in part to the upper right, includes many bright stars from the Trapezium star cluster. M43 is itself a star forming region that displays intricately-laced streams of dark dust -- although it is really composed mostly of glowing hydrogen gas. The entire Orion field is located about 1600 light years away. Opaque to visible light, the picturesque dark dust is created in the outer atmosphere of massive cool stars and expelled by strong outer winds of protons and electrons.