出典:Wikipedia
出典:『Wikipedia』 (2011/05/07 19:19 UTC 版)
Stephenson 2 also known as RSGC2 is a young massive open cluster belonging to the Milky Way galaxy. It was discovered in 1990 in the data obtained by a deep infrared survey. The only members of the cluster that are currently identified are 26 red supergiants—young massive stars undergoing helium burning in their cores. The cluster is located in the constellation Scutum at the distance of about 6 kpc from the Sun. It is likely situated at the intersection of the northern end of the Long Bar of the Milky Way and the inner portion of the Scutum–Centaurus Arm—one of the two major spiral arms.