Английская Википедия:Boötes I
The Boötes Dwarf Galaxy (Boo I dSph) is a galaxy discovered in 2006, which appears faint, with a luminosity of Шаблон:Solar luminosity and an absolute magnitude of –5.8. It lies about Шаблон:Convert away in the constellation Boötes. This dwarf spheroidal galaxy appears to be tidally disrupted[1] by the Milky Way Galaxy, which it orbits, and has two stellar tails that cross over to form a cross.Шаблон:Citation needed Tidally disrupted galaxies usually only form one tail.Шаблон:Citation needed The galaxy appears to be significantly elongated, with an ellipticity of Шаблон:Nowrap.[2]
Like many of the ultrafaint dwarf spheroidals, the entire galaxy appears fainter than the Rigel system (absolute magnitude –7.84).[3] Even so, it is one of the more luminous UFDs.[4] It is metal-poor, like other UFDs, with a mean metallicity of −2.34.[4]
The stellar population of Boötes I is mostly very old stars. The two populations have essentially the same age, 13.4 billion and 13.3 billion years, respectively, with most of the stars being of the latter population.[5]
Notes
- Шаблон:Note labelApparent magnitude = Absolute magnitude + Distance modulus = –5.8[1] + 18.9[1] = 13.1
References
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
- Boötes Dwarf Galaxy at Constellation Guide
Шаблон:Milky Way
Шаблон:Boötes
Шаблон:Sky
