Alternate Names

Sagittarius A*

Type

Supermassive

Location

In the constellation Sagittarius

Finder Chart

Distance

27,000 light-years (8 kiloparsecs)

Mass

4.1 million times the mass of the Sun

Size

Diameter roughly 15 million miles (24 million km).

Discovery Methods

• Measuring the motions of stars

The supermassive black hole at the center of our Milky Way galaxy lies behind dense clouds of gas and dust. The center of the galaxy is a little above the "spout" of the teapot-shaped constellation Sagittarius at the upper right of this photograph. It's about 27,000 light-years away. Recent observations show that the black hole occasionally produces flares of energy, perhaps caused by its complex magnetic field. [Akira Fujii]

This document was last modified: August 21, 2006.