Astronomy:Omicron Pegasi

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Short description: Star in the constellation Pegasus
Omicron Pegasi
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pegasus
Right ascension  22h 41m 45.39893s[1]
Declination +29° 18′ 27.5542″[1]
Apparent magnitude (V) +4.80[2]
Characteristics
Spectral type A1 IV[3]
U−B color index +0.035[4]
B−V color index −0.013±0.002[2]
Astrometry
Radial velocity (Rv)+8.5±0.1[2] km/s
Proper motion (μ) RA: −0.106[1] mas/yr
Dec.: −31.691[1] mas/yr
Parallax (π)11.4116 ± 0.4055[1] mas
Distance290 ± 10 ly
(88 ± 3 pc)
Absolute magnitude (MV)−0.01[3]
Details
Mass2.24[5] M
Luminosity104.24[2] L
Surface gravity (log g)3.77±0.14[5] cgs
Temperature9,956±338[5] K
Metallicity [Fe/H]0.0[3] dex
Rotational velocity (v sin i)6.0±0.2[3] km/s
Age184[5] Myr
Other designations
ο Peg, 43 Pegasi, BD+28°4436, HD 214994, HIP 112051, HR 8641, SAO 90717[6]
Database references
SIMBADdata

ο Pegasi, Latinized as Omicron Pegasi, is a suspected astrometric binary[7] star system in the northern constellation of Pegasus. It is white in hue and visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.80.[2] The distance to this system is approximately 290 light years based on parallax,[1] and it is drifting further away from the Sun with a radial velocity of +8.5 km/s.[2]

The visible component has a stellar classification of A1 IV,[3] matching a subgiant star that has begun to cool, expand and brighten off the main sequence. It has very narrow lines due to a low projected rotational velocity of 6 km/s. The abundances of iron are Sun-like, while it displays an overabundance of heavier elements. Some studies have suggested it is an Am-like star.[3] Omicron Pegasi is an estimated 184 million years old with 2.24 times the mass of the Sun.[5] It is radiating 104[2] times the Sun's luminosity from its photosphere at an effective temperature of 9,956 K.[5]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 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.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 Gray, David F. (April 2014). "Precise Rotation Rates for Five Slowly Rotating a Stars". The Astronomical Journal 147 (4): 13. doi:10.1088/0004-6256/147/4/81. 81. Bibcode2014AJ....147...81G. 
  4. Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode1986EgUBV........0M. 
  5. 5.0 5.1 5.2 5.3 5.4 5.5 David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal 804 (2): 146. doi:10.1088/0004-637X/804/2/146. Bibcode2015ApJ...804..146D. 
  6. "omi Peg". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=omi+Peg. 
  7. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E.