NGC 4755 (aka The Jewel Box Cluster)

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.

A glorious cluster in binoculars of all sizes, it is also spectacular at low powers in a modest-sized (8-12") dobsonian telescope. The rich, red color of the jewel star is a stunning contrast to the blue-white colors of the other bright cluster members. I have observed the object visually with my Canon IS 15x42 binoculars from the OzSky Star Party near Coonabarabran, NSW, Australia as well as with an 18" & 25" dob at the same star party.

I cropped the original TelescopeLive data down to 2185x1910 to avoid the subtle off-axis band created by the bright star Beta Crucis (which would have been in the upper right corner) and reprocessed using Philippe Berhard's monochrome LRGB workflow. Using the SetiAstro StarStretch script on the linear stars-only extraction from StarXterminator really gets the star colors rich!