Astronomy:Omicron1 Centauri

From HandWiki
Short description: Star in the constellation Centaurus


ο1 Centauri
Location of ο1 Cen (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Centaurus
Right ascension  11h 31m 46.07s[1]
Declination −59° 26′ 31.4″[1]
Apparent magnitude (V) +5.13[2]
Characteristics
Evolutionary stage Yellow hypergiant
Spectral type G3 0-Ia[3][4]
B−V color index +1.08[2]
Variable type SRd[5]
Astrometry
Radial velocity (Rv)−20.00[6] km/s
Proper motion (μ) RA: −4.491[1] mas/yr
Dec.: +1.604[1] mas/yr
Parallax (π)0.3254 ± 0.0734[1] mas
Distance10,100+2,700
−1,100
 ly
(3,110+820
−530
 pc)
Absolute magnitude (MV)−9.0[4]
Details
Mass27±5.4[7] M
Radius440±35[7] R
Luminosity68,000[8] L
Surface gravity (log g)0.19[9] cgs
Temperature5,700[8] K
Age10–12[8] Myr
Other designations
HR 4441, HD 100261, CD−58°4100, HIP 56243, SAO 239145, GC 15818, CCDM J11318-5927, AAVSO 1127-58
Database references
SIMBADdata

Omicron1 Centauri (ο1 Cen, ο1 Centauri) is a star in the constellation Centaurus. It is approximately 10,000 light years from Earth, though this is very uncertain.

A light curve for Omicron1 Centauri, adapted from O'Connell (1961)[10]

ο1 Centauri is a yellow G-type supergiant or hypergiant with a mean apparent magnitude of +5.13. Daniel Joseph Kelly O'Connell discovered that the star is a variable star by studying photographic plates taken from 1934 to 1952, and announced his discovery in 1961.[11] It is classified as a semiregular variable star and its brightness varies from magnitude +5.8 to +6.6 with a period of 200 days.[5] Other studies have reported only small brightness variations.[12][13] It is the MK spectral standard for class G3 O-Ia,[14] indicating a highly luminous mass-losing hypergiant star. It has also be classified as F8 Ia0[15] and F7 Ia/ab.[16] The size, luminosity, and distance are equally uncertain.

ο1 Cen forms a very close naked eye double star with ο2 Centauri, a hotter blue supergiant that may be physically associated. ο1 Cen also has an 11th magnitude companion only 13.5" distant,[17] although it appears to be a foreground star unrelated to the other two.[18] ο1 Cen is located very close to V382 Carinae, the brightest yellow hypergiant star in the night sky.

See also

Omicron2 Centauri

References

  1. 1.0 1.1 1.2 1.3 1.4 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 Malyuto, V.; Schmidt-Kaler, T. (1997). "Quantitative spectral classification based on photoelectric spectrum scanner measurements of F-K stars". Astronomy and Astrophysics 325: 693. Bibcode1997A&A...325..693M. 
  3. Keenan, P. C.; Pitts, R. E. (1980). "Revised MK spectral types for G, K, and M stars". Astrophysical Journal Supplement Series 42: 541. doi:10.1086/190662. Bibcode1980ApJS...42..541K. 
  4. 4.0 4.1 Arellano Ferro, A.; Giridhar, Sunetra; Goswami, Aruna (1991). "A new discussion on the M(v) - W(O I 7774 A) relationship for F-G stars in the light of high-resolution data". Monthly Notices of the Royal Astronomical Society 250: 1. doi:10.1093/mnras/250.1.1. Bibcode1991MNRAS.250....1A. 
  5. 5.0 5.1 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. 
  6. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode2006AstL...32..759G. 
  7. 7.0 7.1 Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022-01-01). "Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs". Astronomy and Astrophysics 657: A7. doi:10.1051/0004-6361/202142146. ISSN 0004-6361. Bibcode2022A&A...657A...7K. 
  8. 8.0 8.1 8.2 Kaler, James B., "Omicron 1,2 Centauri", Stars (University of Illinois), http://stars.astro.illinois.edu/sow/omicen.html, retrieved 2017-12-05 
  9. Mallik, Sushma V. (1998). "The central depth of the Ca II triplet lines as a discriminant of chromospheric activity in late type stars". Bulletin of the Astronomical Society of India 26: 479. Bibcode1998BASI...26..479M. 
  10. O'Connell, D. J. K. (1961). "The semi-regular variable o1 Centauri". Ricerche Astronomiche 6 (13): 353–359. Bibcode1961RA......6..353O. 
  11. O'Connell, D. J. K. (1961). "The semi-regular variable o1 Centauri". Ricerche Astronomiche 6 (13): 353–359. Bibcode1961RA......6..353O. https://articles.adsabs.harvard.edu/pdf/1961RA......6..353O. Retrieved 14 December 2024. 
  12. Friedrich, D.; Schoffel, E. (1971). "New Bright Southern Variable Stars". Information Bulletin on Variable Stars 558: 1. Bibcode1971IBVS..558....1F. 
  13. Sterken, C.; Manfroid, J.; Anton, K.; Barzewski, A.; Bibo, E.; Bruch, A.; Burger, M.; Duerbeck, H. W. et al. (1993). "Longterm Photometry of Variables at ESO - Part Two - the Second Data Catalogue 1986-1990". Astronomy and Astrophysics Supplement 102: 79. Bibcode1993A&AS..102...79S. 
  14. Garcia, B. (1989). "A list of MK standard stars". Bulletin d'Information du Centre de Données Stellaires 36: 27. Bibcode1989BICDS..36...27G. 
  15. Mantegazza, L. (1992). "Luminosities of yellow supergiants from near-infrared spectra - Calibration through Magellanic Cloud stars". Astronomy and Astrophysics 265: 527. Bibcode1992A&A...265..527M. 
  16. Sowell, James R. (1990). "A survey of Balmer-line profiles and IRAS fluxes in forty yellow supergiants". Astronomical Journal 100: 834. doi:10.1086/115567. Bibcode1990AJ....100..834S. 
  17. Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal 122 (6): 3466. doi:10.1086/323920. Bibcode2001AJ....122.3466M. 
  18. 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.
Cite error: <ref> tag with name "bailer-jones" defined in <references> is not used in prior text.