Astronomical Observatory: Cool Images

Astr111 Photography Projects, Spring 2007

M60 Elliptical Galaxy, Meaghan Diaz

M60 is a giant elliptical galaxy (NGC 4649), and was discovered April 11, 1779 by Johann Gottfield Koehler, who unintentionally found M58, 59, and 60 while observing a comet which passed close by. M60 is in the eastern most part of the Virgo Cluster that also includes M49, 58-61, 84-91, and 98-100. Elliptical galaxies in general appear as a "luminous bulge" that as a whole do not rotate, and contain older stars and little or no interstellar matter. Giant elliptical galaxies in particular, especially when apart of a cluster like M60 is, owe their massive size to collisions with other smaller galaxies, creating an even larger, spherical, combined mass.

The image above shows the elliptical galaxy as the large, bright ball, and to the upper right is a companion spiral galaxy (NGC 4647). This spiral galaxy is made up of a large center of older stars, and spinning spiral arms that surround it. M60 has a distance from the Earth of 60 million light years, and a linear size of 120,000 light years. The intensity of the center of the galaxy is a result of a massive central core of about 2 million solar masses. It appears yellow-red because elliptical galaxies in general contain older red giant and yellow dwarf stars close to its center.

References:

Fronmert, Hartmut and Kronberg, Christine. "Messier 60." Messier Object Index.

"NGC 4647." The Interactive NGC Catalog Online.

"Elliptical Galaxies." West Kildonan Collegiate Institute.