Alternate Names

NGC 5194/5195, Whirlpool Galaxy

Type

Supermassive

Location

in the constellation Canes Venatici, beneath the Big Dipper

Finder Chart

Distance

27 million light-years

Mass

1 million times the mass of the Sun

Size

Diameter of 4 million miles (6 million km), about four times the diameter of the Sun.

Discovery Methods

• Detection of an accretion disk

What looks like an out-of-focus picture of Christmas lights is really an X-ray image of M51 from the orbiting Chandra X-Ray Observatory. The two galaxies of M51 are filled with clouds of hot gas, which form that reddish background. Individual sources of X-rays -- such as neutron stars and black holes -- show up as points of light. M51’s supermassive black hole is in the bright white blob of light at the center. []

This document was last modified: October 24, 2005.