The Rosette Nebula (NGC 2237) is actually a collection of emission and dark nebulae. It got its name from its distinct flowery shape.

In the hollowed-out centre of the nebula lies an open cluster, NGC 2244, and the young cluster (probably no more than 15,000 years old) is the reason for the nebula's shape, as the radiation and stellar winds from these star are blowing the gas and dust away from the center. The hottest and youngest of the stars have a surface temperature of 20,000 degrees, about 4 times as hot as our sun.

On a clear winter night, the cluster can be seen with the unaided eye, but the entire nebula can be difficult to see in small telescopes because of its large size (it actually appears larger than the moon), causing it to spill out of the field of view.

The nebula and its cluster is between 3,000 and 4,500 light years away, and can be found in the constellation Monoceros.