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.
| 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 |
Characteristics edit
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 edit
- ^ "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.