R Puppis
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Puppis |
| Right ascension | 07h 40m 52.597s[1] |
| Declination | −31° 39′ 40.20″[1] |
| Apparent magnitude (V) | 6.50 - 6.71[2] |
| Characteristics | |
| Spectral type | G2 0-Ia[3] |
| U−B color index | +0.85[4] |
| B−V color index | +1.18[4] |
| Variable type | SRd[2] |
| Astrometry | |
| Radial velocity (Rv) | +68.22[1] km/s |
| Proper motion (μ) | RA: −2.251[1] mas/yr Dec.: +3.222[1] mas/yr |
| Parallax (π) | 0.2440 ± 0.0180 mas[1] |
| Distance | 13,400 ± 1,000 ly (4,100 ± 300 pc) |
| Absolute magnitude (MV) | −7.8[5] |
| Details | |
| Mass | 14.3[6] M☉ |
| Radius | 477+28 −22[7] R☉ |
| Luminosity | 96,600±26,100[7] L☉ |
| Surface gravity (log g) | 0.30[8] cgs |
| Temperature | 5,495; (4,100±68 – 6,500)[8] K |
| Metallicity [Fe/H] | −0.25[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
R Puppis is a variable star in the constellation Puppis. It is a rare yellow hypergiant and a candidate member of the open cluster NGC 2439. It is also an MK spectral standard for the class G2 0-Ia.[9]
Variability
[edit]
R Puppis was identified as a variable star in 1879, and described as having a range of over a magnitude.[11] Numerous observations over the following 100 years failed to confirm the variations, until the 1970s when clear brightness changes were observed.[12] These were confirmed by later observations, but with a total visual amplitude of only about 0.2 magnitudes.[11]
Variable stars such as R Puppis have been described as pseudo-Cepheids, because they lie above the high-luminosity portion of the instability strip and their variations are similar to those of Cepheids although less regular.[11] R Puppis is formally classified as a semiregular variable of type SRd, meaning F, G, or K giants or supergiants.[2]
References
[edit]- ^ a b c d e f Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
- ^ Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373. S2CID 123149047.
- ^ a b Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
- ^ Arellano Ferro, A.; Parrao, L. (1990). "Colour excesses and absolute magnitudes for non-Cepheid F-G supergiants from uvbybeta photometry". Astronomy and Astrophysics. 239: 205. Bibcode:1990A&A...239..205A.
- ^ Anders, F.; Khalatyan, A.; Queiroz, A. B. A.; Chiappini, C.; Ardevol, J.; Casamiquela, L.; Figueras, F.; Jimenez-Arranz, O.; Jordi, C.; Monguio, M.; Romero-Gomez, M.; Altamirano, D.; Antoja, T.; Assaad, R.; Cantat-Gaudin, T.; Castro-Ginard, A.; Enke, H.; Girardi, L.; Guiglion, G.; Khan, S.; Luri, X.; Miglio, A.; Minchev, I.; Ramos, P.; Santiago, B. X.; Steinmetz, M. (2022). "VizieR Online Data Catalog: StarHorse2, Gaia EDR3 photo-astrometric distances (Anders+, 2022)". Vizier Online Data Catalog. Bibcode:2022yCat.1354....0A.
- ^ a b Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c Usenko, I. A.; Kniazev, A. Yu.; Berdnikov, L. N.; Kravtsov, V. V. (2011). "Spectroscopic studies of Cepheids (S Cru, AP Pup, AX Cir, S TrA, T Cru, R Mus, S Mus, U Car) and semiregular bright supergiants (V382 Car, HD 75276, R Pup) in the southern hemisphere". Astronomy Letters. 37 (7): 499. Bibcode:2011AstL...37..499U. doi:10.1134/S1063773711070061. S2CID 122968535.
- ^ Garcia, B. (1989). "A list of MK standard stars". Bulletin d'Information du Centre de Données Stellaires. 36: 27. Bibcode:1989BICDS..36...27G.
- ^ "ASAS All Star Catalogue". The All Sky Automated Survey. Retrieved 8 December 2021.
- ^ a b c Eggen, O. J. (March 1983). "Pseudocepheids. I. R Puppis, HR 4441, HR 4511, and AI CMi". Astronomical Journal. 88: 386–403. Bibcode:1983AJ.....88..386E. doi:10.1086/113323.
- ^ Stift, M. J. (September 1978). "R Pup - a Variable after all". Information Bulletin on Variable Stars. 1473: 1. Bibcode:1978IBVS.1473....1S.
