Rho Pegasi

Summary

Rho Pegasi, Latinized from ρ Pegasi, is a star in the northern constellation of Pegasus, near the southern constellation boundary with Pisces. This is a probable astrometric binary system, as determined by changes to the proper motion of the visible component.[10] It has a white hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.90.[2] The system is located at a distance of approximately 274 light years from the Sun based on parallax,[1] but it is drifting closer with a radial velocity of −10.6 km/s.[4]

Rho Pegasi
Location of ρ Pegasi (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Pegasus
Right ascension 22h 55m 13.66706s[1]
Declination 8° 48′ 58.2387″[1]
Apparent magnitude (V) 4.90[2]
Characteristics
Spectral type A1V[3]
U−B color index +0.00[2]
B−V color index +0.00[2]
Astrometry
Radial velocity (Rv)−10.6±0.9[4] km/s
Proper motion (μ) RA: +80.370[1] mas/yr
Dec.: +13.282[1] mas/yr
Parallax (π)11.9131 ± 0.2232 mas[1]
Distance274 ± 5 ly
(84 ± 2 pc)
Absolute magnitude (MV)+0.01[5]
Details
Mass2.84[6] M
Radius3.1[7] R
Luminosity110[6] L
Surface gravity (log g)3.90[8] cgs
Temperature9,484[6] K
Rotational velocity (v sin i)107[6] km/s
Age331[8] Myr
Other designations
ρ Peg, 50 Peg, BD+08° 4961, GC 31963, HD 216735, HIP 113186, HR 8717, SAO 127839[9]
Database references
SIMBADdata

This visible component is an A-type main-sequence star with a stellar classification of A1V.[3] The star is 331[8] million years old and is spinning with a projected rotational velocity of 107 km/s.[6] It has 2.8[6] times the mass of the Sun and 3.1[7] times the Sun's radius. The star is radiating 110[6] times the luminosity of the Sun from its photosphere at an effective temperature of 9,484 K.[6]

References edit

  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d 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. Bibcode:2002yCat.2237....0D.
  3. ^ a b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819
  4. ^ a b Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  5. ^ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644. Vizier catalog entry
  6. ^ a b c d e f g h Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars". Astronomy & Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. S2CID 55586789. Vizier catalog entry
  7. ^ a b Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures". Astronomy and Astrophysics. 352: 555–562. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. Vizier catalog entry
  8. ^ a b c 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. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607. Vizier catalog entry
  9. ^ "rho Peg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-16.
  10. ^ 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.