Astronomy:AS 314

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Short description: Protoplanetary nebula in the constellation Scutum
V452 Scuti
V452SctLightCurve.png
A visual band light curve for V452 Scuti, plotted from OMC data[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Scutum
Right ascension  18h 39m 26.10612s[2]
Declination −13° 50′ 47.1892″[2]
Apparent magnitude (V) 9.85[3]
Characteristics
Spectral type Protoplanetary nebula[4]
U−B color index +0.12[3]
B−V color index +0.89[3]
Variable type cLBV[5]
Astrometry
Radial velocity (Rv)−77±8[6] km/s
Proper motion (μ) RA: -4.416[6] mas/yr
Dec.: -6.241[6] mas/yr
Parallax (π)0.5853 ± 0.0141[6] mas
Distance5,600 ± 100 ly
(1,710 ± 40 pc)
Details
Luminosity3200[4] L
Temperature10,200[7] K
Other designations
V452 Sct, BD -13°5061, HIP 91477, 2MASS J18392610-1350470
Database references
SIMBADdata

AS 314, also known as V452 Scuti, is a protoplanetary nebula[4] once believed to be a white hypergiant star or luminous blue variable located in the constellation of Scutum. It has an apparent magnitude of 9.85 and can be seen with small telescopes.

Characteristics

AS 314 was poorly studied until the year 2000, when Miroshnichenko et al. incorrectly estimated a distance for this star of around 10 kiloparsecs (32,600 light years), a luminosity 160,000 times that of Sun (L), a radius 200 times the solar radius (R), and an initial mass of 20 solar masses (M). It was also estimated to be losing 2 × 10−5 M each year (in other words, 1 M every 50,000 years) through a very strong stellar wind.[8]

AS 314 has an infrared excess, suggesting that it is shrouded in a circumstellar envelope of dust.[8][9] However, it has not been classified as a bona fide luminous blue variable, but as a candidate.[5]

The Hipparcos parallax and proper motions are large and imply a much closer, and hence less luminous, star.[2] The Hipparcos measurement was later confirmed by the Gaia mission,[6] reclassifying AS 314 as post-AGB star.[4]

References

  1. "The main OGLE Homepage". Warsaw University. http://ogle.astrouw.edu.pl/. 
  2. 2.0 2.1 2.2 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  3. 3.0 3.1 3.2 Kozok, J. R. (1985). "Photometric observations of emission B-stars in the southern Milky Way". Astronomy and Astrophysics Supplement Series 61: 387. Bibcode1985A&AS...61..387K. 
  4. 4.0 4.1 4.2 4.3 Groh, Jose H.; Stassun, Keivan G.; Drout, Maria R.; Murphy, Jeremiah W.; Aghakhanloo, Mojgan; Smith, Nathan (2019), "On the Gaia DR2 distances for Galactic luminous blue variables", Monthly Notices of the Royal Astronomical Society 488 (2): 1760–1778, doi:10.1093/mnras/stz1712, Bibcode2019MNRAS.488.1760S 
  5. 5.0 5.1 Nazé, Y.; Rauw, G.; Hutsemékers, D. (2012). "The first X-ray survey of Galactic luminous blue variables". Astronomy & Astrophysics 538: A47. doi:10.1051/0004-6361/201118040. Bibcode2012A&A...538A..47N. 
  6. 6.0 6.1 6.2 6.3 6.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  7. van Genderen, A.M. (2001). "S Doradus variables in the Galaxy and the Magellanic Clouds". Astronomy & Astrophysics 366 (2): 508–531. doi:10.1051/0004-6361:20000022. Bibcode2001A&A...366..508V. 
  8. 8.0 8.1 Miroshnichenko, A. S.; Chentsov, E. L.; Klochkova, V. G. (2000). "AS?314: A dusty A?type hypergiant". Astronomy and Astrophysics Supplement Series 144 (3): 379. doi:10.1051/aas:2000216. Bibcode2000A&AS..144..379M. http://libres.uncg.edu/ir/uncg/f/A_Miroshnichenko_AS314_2000.pdf. 
  9. Clark, J. S.; Larionov, V. M.; Arkharov, A. (May 2005). "On the population of galactic Luminous Blue Variables". Astronomy and Astrophysics 435 (1): 239–246. doi:10.1051/0004-6361:20042563. Bibcode2005A&A...435..239C. http://oro.open.ac.uk/12987/1/aa2563-04.pdf.