The Boötes Dwarf Galaxy is a faint galaxy, with a total luminosity of 100,000 Sun

Sun

The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

s and an absolute magnitude of –5.8. It lies about 197,000 light-year

Light-year

A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...

s away in the constellation Boötes. This dwarf spheroidal galaxy

Dwarf spheroidal galaxy

Dwarf spheroidal galaxy is a term in astronomy applied to low luminosity galaxies that are companions to the Milky Way and to the similar systems that are companions to the Andromeda Galaxy M31...

 appears to be tidally disrupted by the Milky Way Galaxy, which it orbits

Satellite galaxy

A satellite galaxy orbits a larger galaxy due to gravitational attraction. Although a galaxy is made of a large number of objects which are not connected to each other, it has a center of mass, which represents a weighted average of the positions of each component object...

, and has two stellar tails that cross over to form a cross. Tidally disrupted galaxies usually only form one tail.

Like many of the ultrafaint dwarf spheroidals, the entire galaxy is fainter than the star Rigel

Rigel

Rigel is the brightest star in the constellation Orion and the sixth brightest star in the sky, with visual magnitude 0.18...

(absolute magnitude –6.8).

External links

• The Universe within 500,000 light-years The Satellite Galaxies (Atlas of the Universe)
• Two New Galaxies Orbiting the Milky Way (Ken Croswell) April 19, 2006
• Strange satellite galaxies revealed around Milky Way Kimm Groshong (New Scientist) 17:00 24 April 2006
• New Milky Way companions found: SDSS-II first to view two dim dwarf galaxies (SDSS) May 8, 2006
• Astronomers Find Two New Milky Way Companions (SpaceDaily) May 10, 2006