Pistol star

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Star
pistol star
False color image of pistol star and pistol nebula.
False color image of pistol star and pistol nebula.
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Sagittarius
Right ascension 17 h 46 m 15.3 s
declination -28 ° 50 ′ 4 ″
Apparent brightness K-band: 7.1 to 7.6 mag
Typing
Spectral class pec.
Variable star type SDOR 
Astrometry
distance 25,000  ly
Visual absolute brightness M vis −10.8 mag
Physical Properties
Dimensions approx. 150  M ☉
radius 300 - 340  R ☉
Luminosity

1,700,000  L ☉

Effective temperature 14,000 - 21,000  K
Age ≈ 2,000,000  a
Other names
and catalog entries
2MASS catalog 2MASS J17461524-2850035 [1]
Other names Pistol star, V4647 Sagitarii

The pistol star is a hypergiant from the quintuplet star cluster near the center of the Milky Way .

Details

The pistol star is about 25,000 light years from Earth and is located in the direction of the constellation Sagittarius near the center of the Milky Way. It is about 1.7 million times as bright as the sun . An observation in the visible range of light is not possible, because it is covered by clouds of interstellar dust in the Milky Way plane, otherwise the pistol star would be visible as a 4th mag star despite its distance . It was not observed successfully until the 1990s by the Hubble Space Telescope with the help of infrared cameras.

With over 100 solar masses, the star is extremely massive and radiates as much energy in six seconds as the sun does in a year. Researchers suspect that the star's initial mass was over 200 solar masses. At the end of its life in one to three million years it will probably explode in a supernova .

The star is embedded in the Pistol Nebula , so named because of the similarity of its shape to that of a pistol. This circumstellar nebula essentially consists of matter that was ejected by the Pistol Star in violent eruptions 4,000 to 6,000 years ago and which it makes to glow. The mass of the nebula is estimated to be about 10 solar masses.

literature

  • Donald F. Figer et al .: High-Resolution Infrared Imaging and Spectroscopy of the Pistol Nebula: Evidence for Ejection. In: Astrophysical Journal 525 (November 1999), pp. 759-771, PDF

Web links

Commons : Pistol Star  - collection of images, videos and audio files

Individual evidence

  1. ↑ [FMM95] 3. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed February 6, 2019 .
  2. ↑ V4647 Sgr. In: VSX. AAVSO , accessed February 6, 2019 .