Jewel Box (NGC 4755)
An open cluster of about 100 stars in
the constellation Crux, also known as the Kappa
Crucis Cluster after its most prominent member, a blue
supergiant (visual magnitude 5.89, absolute magnitude -6.10, spectral
type B5Ia). Located near Beta Crucis, the Jewel Box was discovered by Nicolas
Lacaille when he was in South Africa in
1751-52. It is one of the youngest clusters known, with an estimated age
of less than 10 million years. Nearby lies the Coalsack.
||R.A. 12h 53.6m, Dec. -60° 20'
AND STAR CLUSTERS