Messier 32 [M 32]

NASA's Hubble Space Telescope clearly shows the central core of the elliptical galaxy M 32. This green-light image was taken with HST's Wide Field and Planetary Camera (WFPC), in high resolution mode, on 17 August 1991.

The steady increase in brightness of M 32 towards its centre is readily apparent in the image, showing that the stars in M 32 are strongly concentrated towards its nucleus, as if drawn into the centre and held there by the gravitational field of a massive black hole. Theoretical models suggest that the structure of M 32 is consistent with a central 3 million solar mass black hole.

The density of stars at the centre of the image is over 100 million times that within our Sun's neighbourhood. The region shown is 175 light-years on a side at the distance of M 32. The grainy appearance near the borders of the image is due to the Hubble Space Telescope resolving individual stars within M 32.