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

X marks the spot of the black hole at the center of M51 in this Hubble Space Telescope image. The dark stripes that make the X are lanes of dust, which block the light of the brighter stars and gas behind them. Astronomers believe that the black hole is at the intersection of the X. [H. Ford (JHU/STScI)/FOS IDT/NASA]

This document was last modified: October 24, 2005.