C66

A distant globular cluster that lies on the opposite side of the Milky Way's disc, more than 110,000 light years from the Sun. In the skies of Earth, it lies near the end of the long 'tail' of the constellation Hydra as it approaches Libra (and hence the cluster falls somewhat to the west of bright Antares in Scorpius).

C66 has a relatively low mass for a cluster of its type, consisting of a dense group of stars in an opproximately spherical region some 120 light years in diameter. The cluster is unusually old and follows an atypical orbital trajectory that implies that it was not originally part of the Milky Way's system of globular clusters. Instead, it seems to have been captured from another system, most likely from one of the Magellanic Clouds. Its orbit carries around the Milky Way Galaxy at an extraordinarily high velocity - so high, in fact, that it is thought that the cluster will eventually break free of the Galaxy's gravity and escape into intergalactic space.