Messier 70 or M70, also known as NGC 6681, is a globular cluster of stars to be found in the south of Sagittarius. It was discovered by Charles Messier in 1780. The famous comet Hale–Bopp was discovered near this cluster in 1995.
It is about 29,400 light years away from Earth and around from the Galactic Center. It is roughly the same size and luminosity as its neighbour in space, M69. M70 has a very small core radius of and a half-light radius of . This cluster has undergone core collapse, leaving it centrally concentrated with the luminosity distribution following a power law.
There are two distinct stellar populations in the cluster, with each displaying unique abundance abundances. These likely represent different generations of stars. Five known variable stars lie within the broadest radius, the tidal radius, of it, all of which are RR Lyrae variables. The cluster may have two blue stragglers near the core.
Gallery
See also
List of Messier objects
References and footnotes
External links
Messier 70, Galactic Globular Clusters Database page
Globular clusters
Sagittarius (constellation) 070 NGC objects Astronomical objects discovered in 1780