Pistol Star
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The Pistol Star, probably the brightest star in the Milky Way galaxy, is 10 million times as bright as the Sun and about 100 times as massive. The star unleashes as much energy in six seconds as the sun does in one year. It is located approximately 25,000 light years from Earth in the direction of Sagittarius, near the center of the Milky Way. The Pistol Star would be visible to the naked eye as a fourth magnitude star if it were not for interstellar dust clouds hiding it from view; instead, it was discovered by the Hubble Space Telescope in the early 1990s using infrared wavelengths that penetrate the dust. This star is so massive that its future fate cannot be determined for certain, but it is expected that the Pistol Star will die in a brilliant supernova or hypernova in 1 to 3 million years.
Astronomers estimate the star formed 1 to 3 million years ago and was originally as much as 200 times the mass of the Sun before it shed much of its mass in violent eruptions. The Pistol Star may have created the Pistol Nebula, which it illuminates, by ejecting mass under the pressure of its own light; it is thought to have ejected up to 10 solar masses of material in giant outbursts from its outer layers about 4,000 and 6,000 years ago. Its stellar wind is 10 billion times stronger than the Sun's. The size of Pistol Star brings into question current models about how stars are formed, possibly exceeding the current theoretical upper limit. It is possible that the Pistol Star's location near the galaxy's center is partly responsible for its large mass, since current evidence suggests that the star formation process there may favor massive stars.
External link
- Pistol Star Fact Sheet (http://www.solstation.com/x-objects/pistol.htm)
- Further details on the Pistol Star from hubblesite.org (http://hubblesite.org/newscenter/newsdesk/archive/releases/1997/33/text/)de:Pistolenstern