Alternate Names

SAX J1819.3-2525

Type

Stellar mass

Location

in the constellation Sagittarius

Finder Chart

Distance

24,000 to 40,000 light-years (7,400-12,300 parsecs)

Mass

3 to 10 times the mass of the Sun

Size

Diameter roughly 11-37 miles (18-60 km)

Discovery Methods

• Detection of a jet

V4641 Sagittarii

Hot gas from a "normal"� companion star forms a hot disk around a black hole in this artist's concept. The black hole is at the middle of the blue accretion disk at top.

An artist's concept of a microquasar, like V404 Cygni. The black hole is stealing gas from a companion star (left). The gas forms a thin, hot disk around the black hole. When enough gas builds up there is a bright flare-up of X-rays, and jets of charged particles squirt away at close to the speed of light.

This document was last modified: February 13, 2012.