Alternate Names

Nova Cygni 1989, GS 2023+338

Type

Stellar mass

Location

in the constellation Cygnus

Finder Chart

Distance

7,800 light-years (2400 parsecs)

Mass

10 to 15 times the mass of the Sun

Size

Diameter roughly 37-56 miles (60-90 km)

Discovery Methods

• Detection of a jet
• Measuring the motions of a companion star

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. [ESA]

This document was last modified: June 23, 2007.