APOD: 2022 February 18 - Three Clusters in Puppis

Good Red Friday afternoon, Rallypoint, and welcome to the February 18th Astronomy Picture of the Day (APOD): "Three Clusters in Puppis." Based on their ages, star clusters can reveal a lot of information about their host galaxies. Clusters are also a crucial step in determining the distance scale of the universe. So as you might expect, the three clusters in the constellation Puppis have attracted astronomers since the initial discovery of one of them in 1654.

M46 (lower left, 300 million years old) was discovered by Charles Messier in 1771. The larger "star" at about 11 o'clock in M46 is actually a panetary nebula. M47 (right of center, 80 million years old) was first noted by Giovanni Hodiema in 1654; Messier documented its presence again in 1771. Of the three, M47 lies closest to Earth (1,600 light years distant). NGC 2423 (near the top, 750 million years old) is home to an exoplanet discovered in 2007.

See? Clusters can be fun. Well, star clusters, that is.