Astronomy:R Puppis

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Short description: Variable star in the constellation Puppis
R Puppis
Puppis constellation map.svg
Red circle.svg
Location of R Puppis (circled)
Observation data
Equinox J2000.0]] (ICRS)
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[1] mas
Distance13,400 ± 1,000 ly
(4,100 ± 300 pc)
Absolute magnitude (MV)−7.8[5]
Details
Mass14.3[6] M
Radius477[7] R
Luminosity96,607[7] L
Surface gravity (log g)0.30[8] cgs
Temperature6,561[6] K
Metallicity [Fe/H]−0.25[8] dex
Other designations
CD−31°4910, GSC 07106-03582, HIP 37415, HR 2974, HD 62058
Database references
SIMBADdata
NGC 2439, with R Puppis the brightest star

HD 62058, (Variable star designation R Puppis, R Pup) 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

A visual band light curve for R Puppis, plotted from ASAS data[10]

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

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 Samus, N. N. 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. Bibcode2009yCat....102025S. 
  3. Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series 71: 245. doi:10.1086/191373. Bibcode1989ApJS...71..245K. 
  4. 4.0 4.1 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. Bibcode2002yCat.2237....0D. 
  5. 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. Bibcode1990A&A...239..205A. 
  6. 6.0 6.1 Anders, F.; Khalatyan, A.; Queiroz, A. B. A.; Chiappini, C.; Ardevol, J.; Casamiquela, L.; Figueras, F.; Jimenez-Arranz, O. et al. (2022). "VizieR Online Data Catalog: StarHorse2, Gaia EDR3 photo-astrometric distances (Anders+, 2022)". Vizier Online Data Catalog. Bibcode2022yCat.1354....0A. 
  7. 7.0 7.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  8. 8.0 8.1 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. doi:10.1134/S1063773711070061. Bibcode2011AstL...37..499U. 
  9. Garcia, B. (1989). "A list of MK standard stars". Bulletin d'Information du Centre de Données Stellaires 36: 27. Bibcode1989BICDS..36...27G. 
  10. "ASAS All Star Catalogue". The All Sky Automated Survey. http://www.astrouw.edu.pl/asas/?page=aasc. 
  11. 11.0 11.1 11.2 Eggen, O. J. (March 1983). "Pseudocepheids. I. R Puppis, HR 4441, HR 4511, and AI CMi". Astronomical Journal 88: 386–403. doi:10.1086/113323. Bibcode1983AJ.....88..386E. 
  12. Stift, M. J. (September 1978). "R Pup - a Variable after all". Information Bulletin on Variable Stars 1473: 1. Bibcode1978IBVS.1473....1S.