AS 314
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| 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 mas[6] |
| Distance | 5,600 ± 100 ly (1,710 ± 40 pc) |
| Details | |
| Luminosity | 3200[4] L☉ |
| Temperature | 10,200[7] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
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
- ^ "The main OGLE Homepage". OGLE. Warsaw University. Retrieved 19 March 2022.
- ^ a b c Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ a b c Kozok, J. R. (1985). "Photometric observations of emission B-stars in the southern Milky Way". Astronomy and Astrophysics Supplement Series. 61: 387. Bibcode:1985A&AS...61..387K.
- ^ a b c d 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, arXiv:1805.03298, Bibcode:2019MNRAS.488.1760S, doi:10.1093/mnras/stz1712
- ^ a b Nazé, Y.; Rauw, G.; Hutsemékers, D. (2012). "The first X-ray survey of Galactic luminous blue variables". Astronomy & Astrophysics. 538: A47. arXiv:1111.6375. Bibcode:2012A&A...538A..47N. doi:10.1051/0004-6361/201118040. S2CID 43688343.
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ van Genderen, A.M. (2001). "S Doradus variables in the Galaxy and the Magellanic Clouds". Astronomy & Astrophysics. 366 (2): 508–531. Bibcode:2001A&A...366..508V. doi:10.1051/0004-6361:20000022.
- ^ a b Miroshnichenko, A. S.; Chentsov, E. L.; Klochkova, V. G. (2000). "AS?314: A dusty A?type hypergiant" (PDF). Astronomy and Astrophysics Supplement Series. 144 (3): 379. Bibcode:2000A&AS..144..379M. doi:10.1051/aas:2000216.
- ^ Clark, J. S.; Larionov, V. M.; Arkharov, A. (May 2005). "On the population of galactic Luminous Blue Variables" (PDF). Astronomy and Astrophysics. 435 (1): 239–246. Bibcode:2005A&A...435..239C. doi:10.1051/0004-6361:20042563.
