Post by glactus on Apr 30, 2009 11:10:20 GMT
The jewl box in Crux
A favourite with southern Astronomers, The Jewel Box (NGC 4755) is an open cluster in the constellation of Crux, The stars appear to be in a 3D presentation and the different colours add to the charm of this beautiful cluster.
The Jewel Box looks like a star to the unaided eye and appears close to the easternmost star of the Southern Cross, (Beta Crucis), so is only visible from southern latitudes.
One of the youngest known, the Jewel Box cluster has an estimated age of only 7.1 million years, and an apparent magnitude of 4.2. It is located 6,440 light years from Earth and contains around 100 stars.
This famous group of young bright stars was named the Jewel Box from its description by Sir John Herschel as "a casket of variously coloured precious stones," which refers to its appearance in the telescope.
The bright orange star Kappa Crucis contrasts strongly against its predominantly blue, hot companions. Kappa Crucis is a very large (hence very luminous) young star in its red supergiant stage, which paradoxically indicates that its life is drawing to a close.
Credits: Jewel box image.
This is a NASA image.