HD 300933

HD 300933
Location of HD 300933 (circled)
Observation data
Epoch J2000[1]      Equinox J2000[1]
Constellation Vela
Right ascension 10h 38m 02.98879s
Declination −56° 49′ 01.9334″
Apparent magnitude (V) 8.29[2]
Characteristics
Evolutionary stage Red supergiant
Spectral type M2 Iab/Ib[3] + B2V[4]
B−V color index +1.70[2]
J−H color index +1.097[5]
J−K color index +1.500[5]
Astrometry
Radial velocity (Rv)−11.05±0.42[6] km/s
Proper motion (μ) RA: −7.461[1] mas/yr
Dec.: 3.539[1] mas/yr
Parallax (π)0.3216 ± 0.0315 mas[1]
Distance3100[7] pc
Details
HD 300933
Radius806[8] R☉
Temperature3660±170[9] K
Other designations
CD−56°3464, CPD−56°3586, Gaia DR3 5352006438862476288, HD 300933/4, WDS J10380-5649AB, TIC 458199516, TYC 8609-2644-1, GSC 08609-02644, IRAS 10360-5633, 2MASS J10380298-5649019, WISE J103803.02-564901.9[10]
Database references
SIMBADdata

HD 300933 (CPD-56°3586) is a red supergiant of spectral type M2 Iab/Ib[3] in the southern constellation of Vela, close to the border with Carina. With an apparent magnitude of 8.29, it is too faint to be observed by the naked eye, but can be seen through binoculars. It is part of a binary system with a massive B-type main-sequence star (spectral type B2V) designated HD 300934.[4] It is located roughly 3,100 parsecs (10,000 light-years) away from the Solar System, but is approaching at a heliocentric radial velocity of −11.05±0.42 km/s.

Stellar properties

The binary HD 300933/4 is a probable VV Cephei-type star[11] with a composite spectrum similar to that of V381 Cephei (HR 8164), but with weaker emission lines of Fe II, S II, and Ni II[4] (the "II" indicates that the elements are in their singly ionized state in spectroscopic notation[12]). A detailed analysis of the pair was first conducted in 1970, which yielded an absolute magnitude of −5.3 and −2.5 in the V band for HD 300933 and HD 300934, respectively, albeit this was calculated using a distance smaller than modern estimates, at 2,500 parsecs (8,200 light-years).[4] With an updated value of 3100 pc, its KS band absolute magnitude is gauged at −10.8.[7]

HD 300933 displays infrared emissions that imply the existence of circumstellar dust at a temperature of 600 K (327 °C; 620 °F). Despite this, the system shows no signs of ultraviolet extinction or reddening, meaning that the light path from the B star does not cross the wind from the supergiant component. This is thought to be either due to an inclined orbit or an unfavorable orbital phase when it was observed in 1987.[11]

The star is thought to be among the largest stars, though its precise size is highly uncertain; a radius of 806 R☉ can be calculated from the luminosity and effective temperature provided by Healy et al. (2023),[8] whereas Messineo et al. (2019) gives a much smaller estimate of 462 R☉[9] (though they use a far smaller distance of 1574 or 1585 pc, which is inconsistent with the Gaia EDR3 parallax of 0.3216±0.0315 mas[1]).

References

  1. ^ 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.
  2. ^ a b Høg, E.; et al. (February 2000). "The Tycho-2 Catalogue of the 2.5 Million Brightest Stars". Astronomy and Astrophysics. 355 (1): L27–L30. Bibcode:2000A&A...355L..27H.
  3. ^ a b Pantaleoni González, M.; Maíz Apellániz, J.; Barbá, R. H.; Negueruela, I. (1 January 2020). "A Catalog of Galactic Multiple Systems with a Red Supergiant and a B Star". Research Notes of the AAS. 4 (1): 12. arXiv:2001.11680. Bibcode:2020RNAAS...4...12P. doi:10.3847/2515-5172/ab712b. ISSN 2515-5172.
  4. ^ a b c d Keenan, Philip C. (1970). "The Composite Spectrum of CPD-56°3586 and the Luminosity of its Supergiant Component". The Astrophysical Journal. 162: 199. Bibcode:1970ApJ...162..199K. doi:10.1086/150646. ISSN 0004-637X.
  5. ^ a b Cutri, Roc M.; Skrutskie, Michael F.; Van Dyk, Schuyler D.; Beichman, Charles A.; Carpenter, John M.; Chester, Thomas; Cambresy, Laurent; Evans, Tracey E.; Fowler, John W.; Gizis, John E.; Howard, Elizabeth V.; Huchra, John P.; Jarrett, Thomas H.; Kopan, Eugene L.; Kirkpatrick, J. Davy; Light, Robert M.; Marsh, Kenneth A.; McCallon, Howard L.; Schneider, Stephen E.; Stiening, Rae; Sykes, Matthew J.; Weinberg, Martin D.; Wheaton, William A.; Wheelock, Sherry L.; Zacarias, N. (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues. 2246: II/246. Bibcode:2003yCat.2246....0C.
  6. ^ 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.
  7. ^ a b Munari, U; Traven, G; Masetti, N; Valisa, P; Righetti, G-L; Hambsch, F-J; Frigo, A; Čotar, K; De Silva, G M; Freeman, K C; Lewis, G F; Martell, S L; Sharma, S; Simpson, J D; Ting, Y-S; Wittenmyer, R A; Zucker, D B (6 July 2021). "The GALAH survey and symbiotic stars – I. Discovery and follow-up of 33 candidate accreting-only systems". Monthly Notices of the Royal Astronomical Society. 505 (4): 6121–6154. arXiv:2104.02686. doi:10.1093/mnras/stab1620. ISSN 0035-8711.
  8. ^ a b Healy, Sarah; Horiuchi, Shunsaku; Molla, Marta Colomer; Milisavljevic, Dan; Tseng, Jeff; Bergin, Faith; Weil, Kathryn; Tanaka, Masaomi (23 March 2024). "Red Supergiant Candidates for Multimessenger Monitoring of the Next Galactic Supernova". Monthly Notices of the Royal Astronomical Society. 529 (4): 3630–3650. arXiv:2307.08785. Bibcode:2024MNRAS.529.3630H. doi:10.1093/mnras/stae738. ISSN 0035-8711.
  9. ^ a b Messineo, M.; Brown, A.G.A. (2019). "K-M stars of class I candidate RSGs in Gaia DR2". VizieR On-line Data Catalog. Bibcode:2019yCat..51580020M. doi:10.26093/CDS/VIZIER.51580020. Record for this source at VizieR. Originally published in Bibcode:2019AJ....158...20M.
  10. ^ "HD 300933". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 29 November 2024.
  11. ^ a b Buss, Richard H., Jr.; Snow, Theodore P., Jr. (1988). "Hot components and circumstellar grains in M supergiant syncretic binaries". The Astrophysical Journal. 335: 331. Bibcode:1988ApJ...335..331B. doi:10.1086/166931. ISSN 0004-637X.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. ^ Phillips, Kenneth J. H. (1992). Guide to the Sun. Cambridge: Cambridge University Press. p. 92. ISBN 0-521-39788-X..