Monster Galaxy with an Unusual Core

The giant elliptical galaxy in the center of this image is the most massive and brightest member of the galaxy cluster Abell 2261. Spanning a little more than one million light-years, the galaxy is about 10 times the diameter of our Milky Way Galaxy. The immense object, dubbed A2261-BCG, is a member of an unusual class of galaxies with a diffuse core filled with a fog of starlight. Normally, astronomers would expect to see a concentrated peak of light around a central black hole. The Hubble observations revealed that the galaxy's less-concentrated core measures about 10,000 light-years across. The observations present a mystery, and studies of this galaxy may provide insight into how black holes shape the cores of galaxies.