M61

M61 or NGC 4303

M61 is a barred spiral galaxy located in the nearby Virgo Cluster of Galaxies. Visible in M61 are a host of features common to spiral galaxies: bright spiral arms, a central bar, dust lanes, and bright knots of stars. M61, also known as NGC 4303, in similar to our own Milky Way Galaxy. M61 was discovered by telescope in 1779 twice on the same day, but one observer initially mistook the galaxy for a comet. Light from M61 takes about 60 million years to reach us. Recent observations of M61 have detected unpredicted high velocity gas moving in its halo.

M61 is one of the larger galaxies in the Virgo cluster; its 6 arc minutes of diameter correspond to about 100,000 light years, similar to the diameter of the Milky Way galaxy. (SEDS) It is classified as a SABbc spiral galaxy.

Sources

• M61 in NASA Galaxy gallery
• M61 in NASA Astronomy Picture of the Day
• SEDS file on M61
• National Optical Astronomy Observatory posting.