Lambda Pegasi
  | |
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Pegasus |
| Right ascension | 22h 46m 31.87786s[1] |
| Declination | +23° 33′ 56.3561″[1] |
| Apparent magnitude (V) | 3.93[2] |
| Characteristics | |
| Spectral type | G8II-III[3] |
| U−B color index | +0.93[2] |
| B−V color index | +1.07[2] |
| Astrometry | |
| Radial velocity (Rv) | -4.15[4] km/s |
| Proper motion (μ) | RA: 55.75[1] mas/yr Dec.: -10.15[1] mas/yr |
| Parallax (π) | 8.93±0.24 mas[1] |
| Distance | 365 ± 10 ly (112 ± 3 pc) |
| Absolute magnitude (MV) | -1.45[5] |
| Details[6] | |
| Mass | 3.944±0.152 M☉ |
| Radius | 28.254±1.633 R☉ |
| Luminosity | 397±30 L☉ |
| Surface gravity (log g) | 2.12±0.08 cgs |
| Temperature | 4,848±109 K |
| Metallicity [Fe/H] | −0.07±0.06 dex |
| Rotational velocity (v sin i) | 8.0[7] km/s |
| Other designations | |
| Ligong, λ Peg, 47 Peg, BD+22°4709, FK5 859, GC 31776, GJ 4295, HD 215665, HIP 112440, HR 8667, SAO 90775, IRAS 22441+2318 | |
| Database references | |
| SIMBAD | data |
Lambda Pegasi, also named Ligong,[8] is a fourth-magnitude star in the constellation Pegasus. It lies near Mu Pegasi, to the southwest of the brighter Beta Pegasi (Scheat).
Nomenclature
Lambda Pegasi (Latinized from λ Pegasi, abbreviated λ Peg) is the star's Bayer designation. It traditionally shared the Arabic name Sadalbari with Mu Pegasi.[9]
In Chinese astronomy, this star is part of the constellation Ligong (離宮), representing a secondary or temporary palace. The IAU Working Group on Star Names adopted the name Ligong for this star on 13 August 2026, after this Chinese constellation.[8]
Properties
λ Pegasi is a yellow giant with stellar classification G8II-III. With a mass of 1.5 M☉ and radius that is 28.5 R☉, the star boasts a bolometric luminosity that is roughly 390 L☉.[3] Its apparent magnitude was calibrated in 1983 at 3.96, yielding an absolute magnitude of -1.45.[5] Parallax calculations place the star at a distance of roughly 112 parsecs from Earth, or 365 ± 10 light years away,[1] about three times the distance of its line-of-sight double μ Pegasi.
References
- 1 2 3 4 5 6 van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- 1 2 3 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.
- 1 2 Smith, G. (November 1998). "Stellar atmospheric parameters for the giant stars MU Pegasi and lambda Pegasi" (PDF). Astronomy & Astrophysics. 339: 531–536. Bibcode:1998A&A...339..531S. Retrieved 2012-08-28.
- ↑ Soubiran, C; Bienaymé, O; Mishenina, T. V; Kovtyukh, V. V (2008). "Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants". Astronomy and Astrophysics. 480 (1): 91–101. arXiv:0712.1370. Bibcode:2008A&A...480...91S. doi:10.1051/0004-6361:20078788. S2CID 16602121.
- 1 2 "λ Pegasi". Wolfram Alpha. Retrieved 2012-08-28.
- ↑ Soubiran, C.; Creevey, O. L.; Lagarde, N.; Brouillet, N.; Jofré, P.; Casamiquela, L.; Heiter, U.; Aguilera-Gómez, C.; Vitali, S.; Worley, C.; de Brito Silva, D. (2024-02-01). "Gaia FGK benchmark stars: Fundamental Teff and log g of the third version". Astronomy and Astrophysics. 682: A145. arXiv:2310.11302. Bibcode:2024A&A...682A.145S. doi:10.1051/0004-6361/202347136. ISSN 0004-6361. Lambda Pegasi's database entry at VizieR.
- ↑ Hekker, S.; Meléndez, J. (December 2007). "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters". Astronomy and Astrophysics. 475 (3): 1003–1009. arXiv:0709.1145. Bibcode:2007A&A...475.1003H. doi:10.1051/0004-6361:20078233. S2CID 10436552.
- 1 2 "IAU Catalog of Star Names". Retrieved 16 August 2026.
- ↑ Allen, R. H. (1899), Star Names: Their Lore and Meaning, p. 328
