出典:Wikipedia
出典:『Wikipedia』 (2011/06/29 18:28 UTC 版)
NGC 2129 is an open cluster in the constellation Gemini. It has an angular distance of 2.5 arcminutes and is approximately 2.2 ± 0.2 kpc (~7,200 light years) from the Sun inside the Local spiral arm. At that distance, the angular size of the cluster corresponds to a diameter of about 10.4 light years. NGC 2129 is a very young cluster whose age has been estimated at 10 million years..