NGC 1851

NGC 1851 (also known as Caldwell 73)[9] is a relatively massive[3] globular cluster located in the southern constellation of Columba. It has one of the highest concentrations known for Galactic globular clusters.[3] The stellar components shows two separate populations of subgiant stars, with the brighter branch being more concentrated in the outer regions of the cluster.[10] NGC 1851 is an estimated 9.2[6] billion years old with 551,000 times the mass of the Sun. (Wikipedia)