Researchers detected the Gaia 1 cluster applying automated"star gauging" to the Gaia observatory's data on star locations.[3] This analysis surprisingly indicated a prominent concentration of stars, previously unknown and uncataloged, adjacent to Sirius. Gaia observed a cluster population of approximately 1,200 stars down to Gaiamagnitude 19. Analysis of2MASS data for those stars shows ared giant branch and a pronouncedred clump that allows theabsolute magnitude of the stars to be deduced and the distance calculated. Fitting the red giant branch also allows the age of the cluster to be calculated at 6.3 billion years.[1]
