AS 314

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Star
AS 314
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation sign
Right ascension 18 h 39 m 26.1 s
declination -13 ° 50 ′ 47.2 ″
Apparent brightness 9.85 likes
Typing
B − V color index +0.89 
U − B color index +0.12 
Spectral class A0Ia +
Variable star type cLBV 
Astrometry
Radial velocity (76.65 ± 8.30) km / s
parallax (0.62 ± 0.05)  mas
Proper movement 
Rec. Share: (−4.49 ± 0.08)  mas / a
Dec. portion: (-6.05 ± 0.07)  mas / a
Physical Properties
Effective temperature 10,200  K
Other names
and catalog entries
Bonn survey BD -13 ° 5061
Hipparcos catalog HIP 91477 [1]
Tycho catalog TYC 5704-473-1 [2]
2MASS catalog 2MASS J18392610-1350470 [3]
Other names V452 Scuti

The star AS 314 , also known as V452 Scuti , is a star in the constellation Schild (Scutum) and can be observed with small telescopes with its apparent magnitude of 9.85 mag .

First investigations

AS 314 was hardly investigated when Miroschnytschenko et al. identified him from observations in 2000 as a white supergiant with an absolute magnitude of -8 magnitudes and a candidate for a bright blue variable . This would result in a distance of around 10 kiloparsecs (around 32,600 light years ) and a luminosity of 160,000 times the solar luminosity L ☉ . Even then, these data contradicted the parallax measured by Hipparcos, which was also quoted in the same work.

The observed infrared excess was interpreted as a dust cover , which might have produced an outbreak of the star in its past as a bright blue variable, because its position in the Hertzsprung-Russell diagram placed it in the vicinity of such stars. In any case, it is not classified as a "flawless" bright blue variable (LBV), but only as a candidate (cLBV).

Recent measurements

The Hipparcos parallaxes and proper motions are large and suggest a much closer and therefore less luminous star. More recent measurements from the Gaia mission , in turn, indicate a greater distance. While Hipparcos have a parallax of 3.58 (Perryman 1997) resp. 4.29 (van Leeuwen 2007) determined, determined Gaia a parallax of 0.91 ( Gaia DR1 ), resp. 0.62 ( Gaia DR2 ). Converted to a distance, Hipparcos would have located the star at about 1000 light years away, while Gaia now suspects it to be 5000 light years away with a much smaller error. In any case, the more recent measurements seem to indicate a significantly shorter distance than 10 kiloparsecs, which means that the star would also be less luminous than initially assumed.

Individual evidence

  1. ↑ a b c d BD-13 5061. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed June 10, 2019 .
  2. ↑ a b c J. R. Kozok: Photometric observations of emission B-stars in the southern Milky Way . In: Astronomy and Astrophysics Supplement Series . 61, 1985, p. 387. bibcode : 1985A & AS ... 61..387K .
  3. ↑ a b c A. S. Miroshnichenko, EL Chentsov, VG Klochkova: AS? 314: A dusty A? Type hypergiant . In: Astronomy and Astrophysics Supplement Series . 144, No. 3, 2000, p. 379. bibcode : 2000A & AS..144..379M . doi : 10.1051 / aas: 2000216 .
  4. ↑ a b Y. Naze, G. Rauw, D. Hutsemékers: The first X-ray survey of Galactic luminous blue variable . In: Astronomy & Astrophysics . 538, 2012, p. A47. arxiv : 1111.6375 . bibcode : 2012A & A ... 538A..47N . doi : 10.1051 / 0004-6361 / 201118040 . ; there quoted from Miroshnichenko 2000
  5. ↑ AM van Genderen: S Doradus variables in the Galaxy and the Magellanic Clouds . In: Astronomy & Astrophysics . 366, No. 2, 2001, pp. 508-531. bibcode : 2001A & A ... 366..508V . doi : 10.1051 / 0004-6361: 20000022 .
  6. ^ JS Clark, VM Larionov, A. Arkharov: On the population of galactic Luminous Blue Variables . In: Astronomy and Astrophysics . 435, No. 1, May 2005, pp. 239-246. bibcode : 2005A & A ... 435..239C . doi : 10.1051 / 0004-6361: 20042563 .
  7. ^ F. Van Leeuwen: Validation of the new Hipparcos reduction . In: Astronomy and Astrophysics . 474, No. 2, 2007, p. 653. arxiv : 0708.1752 . bibcode : 2007A & A ... 474..653V . doi : 10.1051 / 0004-6361: 20078357 .