Xi Pegasi

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Xi Pegasi
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pegasus
Right ascension 22h 46m 41.58118s[1]
Declination +12° 10′ 22.3854″[1]
Apparent magnitude (V) 4.195[2] + 11.70[3]
Characteristics
Spectral type F6V[4] + M3.5[5]
U−B color index −0.015[2]
B−V color index +0.502[2]
Astrometry
Radial velocity (Rv) −5.3[6] km/s
Proper motion (μ) RA: +234.18[1] mas/yr
Dec.: −493.29[1] mas/yr
Parallax (π) 61.36 ± 0.19[1] mas
Distance 53.2 ± 0.2 ly
(16.30 ± 0.05 pc)
Details
Xi Peg A
Mass 1.17[7] M
Radius 1.86[7] R
Luminosity 4.5[7] L
Surface gravity (log g) 3.97 ± 0.07[7] cgs
Temperature 6,178 ± 26[7] K
Metallicity [Fe/H] −0.27 ± 0.03[7] dex
Rotational velocity (v sin i) 12.67[8] km/s
Age 5.0±0.5[7] Gyr
Xi Peg B
Mass 0.32[9] M
Temperature 3,569[3] K
Metallicity [Fe/H] −0.25[3] dex
Other designations
46 Peg, GJ 872, HD 215648, HIP 112447, HR 8665, SAO 108165.[10]

Xi Pegasi (ξ Peg, ξ Pegasi) is the Bayer designation for a double star in the northern constellation of Pegasus, the winged horse. Located in the horse's neck, the primary component is an F-type main sequence star that is visible to the naked eye with an apparent visual magnitude of 4.2.[2] It is 86% larger and 17% more massive that the Sun, radiating 4.5 times the solar luminosity.[7] Based upon parallax measurements taken with the Hipparcos spacecraft, it is located 53.2 ± 0.2 light years from the Sun.[1]

The primary has been examined for the presence of an infrared excess that might indicate the presence of a debris disk, but none has been discovered.[11] The common proper motion companion, NLTT 54820, is a twelfth magnitude red dwarf located at an angular separation of 11.4″ along a position angle of 96.9°.[12] This corresponds to a projected physical separation of 192.3 AU.[11]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752free to read, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d Kozok, J. R. (September 1985), "Photometric observations of emission B-stars in the southern Milky Way", Astronomy and Astrophysics Supplement Series, 61: 387–405, Bibcode:1985A&AS...61..387K. 
  3. ^ a b c Rojas-Ayala, Bárbara; et al. (April 2012), "Metallicity and Temperature Indicators in M Dwarf K-band Spectra: Testing New and Updated Calibrations with Observations of 133 Solar Neighborhood M Dwarfs", The Astrophysical Journal, 748 (2): 93, arXiv:1112.4567free to read, Bibcode:2012ApJ...748...93R, doi:10.1088/0004-637X/748/2/93. 
  4. ^ Gray, R. O.; Graham, P. W.; Hoyt, S. R. (April 2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. II. Basic Parameters of Program Stars and the Role of Microturbulence", The Astronomical Journal, 121 (4): 2159–2172, Bibcode:2001AJ....121.2159G, doi:10.1086/319957. 
  5. ^ Bidelman, W. P. (October 1985), "G. P. Kuiper's spectral classifications of proper-motion stars", Astrophysical Journal Supplement Series, 59: 197−227, Bibcode:1985ApJS...59..197B, doi:10.1086/191069. 
  6. ^ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington D.C., Bibcode:1953GCRV..C......0W. 
  7. ^ a b c d e f g h Ghezzi, L.; et al. (September 2010), "Stellar Parameters and Metallicities of Stars Hosting Jovian and Neptunian Mass Planets: A Possible Dependence of Planetary Mass on Metallicity", The Astrophysical Journal, 720 (2): 1290–1302, arXiv:1007.2681free to read, Bibcode:2010ApJ...720.1290G, doi:10.1088/0004-637X/720/2/1290. 
  8. ^ Martínez-Arnáiz, R.; et al. (September 2010), "Chromospheric activity and rotation of FGK stars in the solar vicinity. An estimation of the radial velocity jitter", Astronomy and Astrophysics, 520: A79, arXiv:1002.4391free to read, Bibcode:2010A&A...520A..79M, doi:10.1051/0004-6361/200913725. 
  9. ^ Tokovinin, Andrei (April 2014), "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs", The Astronomical Journal, 147 (4): 14, arXiv:1401.6827free to read, Bibcode:2014AJ....147...87T, doi:10.1088/0004-6256/147/4/87, 87. 
  10. ^ "ksi Peg -- High proper-motion Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2015-12-10. 
  11. ^ a b Moro-Martín, A.; et al. (March 2015), "Does the Presence of Planets Affect the Frequency and Properties of Extrasolar Kuiper Belts? Results from the Herschel Debris and Dunes Surveys", The Astrophysical Journal, 801 (2): 28, arXiv:1501.03813free to read, Bibcode:2015ApJ...801..143M, doi:10.1088/0004-637X/801/2/143, 143. 
  12. ^ Gould, Andrew; Chanamé, Julio (February 2004), "New Hipparcos-based Parallaxes for 424 Faint Stars", The Astrophysical Journal Supplement Series, 150 (2): 455–464, arXiv:astro-ph/0309001free to read, Bibcode:2004ApJS..150..455G, doi:10.1086/381147. 

External links[edit]

  • Kaler, James B., "Xi Pegasi", Stars, University of Illinois, retrieved 2016-01-07.