Because of its brilliance, the bright portion of NGC 2024 is also known as the Christmas Tree Nebula. Many astronomers have studied this nebula over the years, including Edwin Hubble, who published a paper on it in 1922. Although the NGC 2024 molecular cloud is composed primarily of hydrogen, other molecules have been detected in it, including nitrous oxide, carbonyl sulfide, formaldehyde, silicon oxide, ammonia, and methanol. The discovery of these substances demonstrates that molecular clouds play an important role in the cycle of stellar birth and death. The gas and dust of the cloud were once contained in ancient stars, whose material was strewn into the galaxy by stellar winds and supernova
