Heavyweight of the Leo Triplet, Galaxy Messier 66

The disturbed spiral galaxy Messier 66 (M66) is located about 35 million light-years away in the direction of the constellation Leo, the Lion. Together with Messier 65 and NGC 3628, M66 is one-third of the Leo Triplet, a trio of interacting spiral galaxies, part of the larger Messier 66 group. Messier 66 is the largest of the three galaxies. Like the Milky Way, it is approximately 100,000 light-years across. Unlike our galaxy, it displays asymmetric spiral arms and an apparently displaced core. Its peculiar anatomy is most likely caused by the gravitational pull of the other two members of the trio. This image was taken by Hubble’s Advanced Camera for Surveys and shows only about a third of the galaxy. Interestingly, M66 has hosted three supernovas within the last 29 years. The latest one, in 2009, was bright enough to be seen in amateur-sized telescopes.