Type

Stellar mass

Location

In the constellation Ursa Major

Finder Chart

Distance

6,000 light-years

Mass

7 times the mass of the Sun

Size

Diameter 26 miles (42 km), equal to the size of a large city.

Discovery Methods

• Measuring the motions of stars
• Measuring X-rays

XTE J1118+480

This chart shows the looping orbital path that XTE J1118+480 follows through the galaxy. This path leads some astronomers to suspect that the black hole was born in a globular star cluster outside the galaxy's disk.

The X-ray spectrum of XTE J1118+480 recorded by Chandra X-Ray Observatory in 2000.

This document was last modified: November 19, 2009.