Jewel Box (star cluster)
| Jewel Box | |
|---|---|
| Observation data (J2000 epoch) | |
| Right ascension | 12h 53m 42s |
| Declination | −60° 22.0′ |
| Distance | 6.50 kly (1.99 kpc) |
| Physical characteristics | |
| Mass | – M☉ |
| Radius | – |
| Estimated age | 16 Myr |
| – | |
| Other designations | Herschel's Jewel Box, κ Crucis cluster, NGC 4755, Cr 264, Caldwell 94 |
| Associations | |
| Constellation | Crux |
The Jewel Box (also known as the Kappa Crucis cluster, NGC 4755, or Caldwell 94) is an open cluster in the constellation Crux, originally discovered by Nicolas Louis de Lacaille in 1751–1752. This cluster was later named the Jewel Box by John Herschel when he described its telescopic appearance as "... a superb piece of fancy jewellery". It is easily visible to the naked eye as a hazy star some 1.0° southeast of the first-magnitude star Mimosa (Beta Crucis). This hazy star was given the Bayer star designation "Kappa Crucis", from which the cluster takes one of its common names. The modern designation Kappa Crucis has been assigned to one of the stars in the base of the A-shaped asterism of the cluster.
This cluster is one of the youngest known, with an estimated age of 14 million years. It has a total integrated magnitude 4.2, is located 1.99 kpc, or 6497 light years from Earth, and contains just over 100 stars.