Astronomy:2 Pegasi

From HandWiki
Short description: Star in the constellation Pegasus
2 Pegasi
Location of 2 Pegasi (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pegasus
Right ascension  21h 29m 56.89545s[1]
Declination 23° 38′ 19.8170″[1]
Apparent magnitude (V) 4.52[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M1+III[4]
U−B color index +1.93[5]
B−V color index +1.62[5]
Astrometry
Radial velocity (Rv)−18.92[6] km/s
Proper motion (μ) RA: +24.74[1] mas/yr
Dec.: +3.63[1] mas/yr
Parallax (π)8.28 ± 0.18[1] mas
Distance394 ± 9 ly
(121 ± 3 pc)
Absolute magnitude (MV)−0.89[2]
Details
Mass1.2[7] M☉
Radius55[8] R☉
Luminosity646[9] L☉
Surface gravity (log g)1.57[7] cgs
Temperature3,921[9] K
Metallicity [Fe/H]−0.16[7] dex
Other designations
2 Peg, NSV 25624, BD+23°4325, FK5 1565, GC 30109, HD 204724, HIP 106140, HR 8225, SAO 89752, CCDM J21299+2338A, WDS J21299+2338A[10]
Database references
SIMBADdata

2 Pegasi is a single[11] star in the constellation Pegasus, located approximately 394 light years away from the Sun based on parallax.[1] It is visible to the naked eye as a faint, red-hued star with an apparent visual magnitude of 4.52.[2] The object is moving closer to the Earth with a heliocentric radial velocity of −19 km/s.[6] It has a magnitude 12.7 visual companion, designated component B, at an angular separation of 30.4″.[12]

This is an aging red giant star with a stellar classification of M1+III,[4] currently on the asymptotic giant branch,[3] having exhausted the hydrogen at its core and evolved away from the main sequence. The star has expanded to an estimated 55 times the radius of the Sun.[8] It is radiating 646 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 3,921 K.

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V.  Vizier catalog entry
  2. ↑ 2.0 2.1 2.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.  Vizier catalog entry
  3. ↑ 3.0 3.1 Eggen, O. J. (1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal 104: 275. doi:10.1086/116239. Bibcode: 1992AJ....104..275E. 
  4. ↑ 4.0 4.1 Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H 5050. Bibcode: 1995yCat.5050....0H. 
  5. ↑ 5.0 5.1 Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers 42 (2): 443. Bibcode: 2014JAVSO..42..443M. Vizier catalog entry
  6. ↑ 6.0 6.1 Famaey, B.; Pourbaix, D.; Frankowski, A.; Van Eck, S.; Mayor, M.; Udry, S.; Jorissen, A. (2009). "Spectroscopic binaries among Hipparcos M giants". Astronomy and Astrophysics 498 (2): 627. doi:10.1051/0004-6361/200810698. Bibcode: 2009A&A...498..627F. 
  7. ↑ 7.0 7.1 7.2 Khalatyan, A.; Anders, F.; Chiappini, C.; Queiroz, A. B. A.; Nepal, S.; Dal Ponte, M.; Jordi, C.; Guiglion, G. et al. (2024). "Transferring spectroscopic stellar labels to 217 million Gaia DR3 XP stars with SHBoost". Astronomy and Astrophysics 691: A98. doi:10.1051/0004-6361/202451427. Bibcode: 2024A&A...691A..98K. 
  8. ↑ 8.0 8.1 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. Bibcode: 2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  9. ↑ 9.0 9.1 Lehtinen, Jyri J.; Spada, Federico; Käpylä, Maarit J.; Olspert, Nigul; Käpylä, Petri J. (2020). "Common dynamo scaling in slowly rotating young and evolved stars". Nature Astronomy 4 (7): 658. doi:10.1038/s41550-020-1039-x. Bibcode: 2020NatAs...4..658L. 
  10. ↑ "2 Peg". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=2+Peg. 
  11. ↑ 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. Bibcode: 2008MNRAS.389..869E. 
  12. ↑ 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. Bibcode: 2001AJ....122.3466M.  Vizier catalog entry



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:2_Pegasi&oldid=3941743"