Summary
33 Pegasi is the Flamsteed designation for a visual binary star in the northern constellation of Pegasus. It has an apparent visual magnitude of 6.2,[2] placing it near the limit of naked eye visibility. Measurements show an annual parallax shift of 0.0298125″,[1] which is equivalent to a distance of 109 ly (33 pc) from the Sun. It is drifting further away with a radial velocity of 24 km/s.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Pegasus |
| Right ascension | 22h 23m 39.565s[1] |
| Declination | 20° 50′ 53.84″[1] |
| Apparent magnitude (V) | 6.203[2] (6.391 + 9.287)[3] |
| Characteristics | |
| Spectral type | F7 V[4] |
| B−V color index | 0.518±0.004[5] |
| Astrometry | |
| Radial velocity (Rv) | 23.8±0.4[2] km/s |
| Proper motion (μ) | RA: +333.057 mas/yr[1] Dec.: −10.827 mas/yr[1] |
| Parallax (π) | 29.8125 ± 0.0436 mas[1] |
| Distance | 109.4 ± 0.2 ly (33.54 ± 0.05 pc) |
| Absolute magnitude (MV) | 3.55[2] |
| Details | |
| 33 Peg A | |
| Mass | 1.28[6] M☉ |
| Radius | 1.29+0.15 −0.14[7] R☉ |
| Luminosity | 2.850+0.007 −0.008[7] L☉ |
| Surface gravity (log g) | 4.29[8] cgs |
| Temperature | 6,169[9] K |
| Metallicity [Fe/H] | –0.18[9] dex |
| Rotational velocity (v sin i) | 6[2] km/s |
| Age | 4.1[9] Gyr |
| 33 Peg B | |
| Mass | 0.80[6] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
The primary component of this system is a main sequence star with a visual magnitude of 6.4[3] and a stellar classification of F7 V.[4] It is nearly as old as the Sun with an estimated age of 4.1 billion years, but has a lower abundance of elements other than hydrogen and helium. The star has 1.3 times the mass[6] and radius[7] of the Sun. The stellar atmosphere has an effective temperature of 6,169 K,[9] giving it the yellow-white glow of an F-type star.[11]
A faint, magnitude 9.3 companion star is located at an angular separation of 0.420 arc seconds along a position angle of 0.0°.[3] The pair have a projected separation of 15.6 AU[6] with an orbital period of about 250 years.[12]
References edit
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b c d e f Nordström, B.; et al. (May 2004), "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14 000 F and G dwarfs", Astronomy and Astrophysics, 418: 989–1019, arXiv:astro-ph/0405198, Bibcode:2004A&A...418..989N, doi:10.1051/0004-6361:20035959, S2CID 11027621.
- ^ a b c Fabricius, C.; Makarov, V. V. (April 2000), "Two-colour photometry for 9473 components of close Hipparcos double and multiple stars", Astronomy and Astrophysics, 356: 141–145, Bibcode:2000A&A...356..141F.
- ^ a b Harlan, E. A.; Taylor, D. C. (March 1970), "MK classification for F- and G-type stars. II", Astronomical Journal, 75 (2): 165–166, Bibcode:1970AJ.....75..165H, doi:10.1086/110956.
- ^ 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.
- ^ a b c d Tokovinin, A.; Kiyaeva, O. (2015), "Eccentricity distribution of wide binaries", Monthly Notices of the Royal Astronomical Society, 456 (2): 2070, arXiv:1512.00278, Bibcode:2016MNRAS.456.2070T, doi:10.1093/mnras/stv2825, S2CID 1615080.
- ^ a b c 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.
- ^ Boesgaard, Ann Merchant; et al. (2004), "The Correlation of Lithium and Beryllium in F and G Field and Cluster Dwarf Stars", The Astrophysical Journal, 613 (2): 1202–1212, Bibcode:2004ApJ...613.1202B, doi:10.1086/423194.
- ^ a b c d Casagrande, L.; et al. (June 2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy & Astrophysics, 530: A138, arXiv:1103.4651, Bibcode:2011A&A...530A.138C, doi:10.1051/0004-6361/201016276, S2CID 56118016.
- ^ "* 33 Peg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2013-12-31.
- ^ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on March 18, 2012, retrieved 2012-01-16.
- ^ Tokovinin, Andrei (April 2014), "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs", The Astronomical Journal, 147 (4): 14, arXiv:1401.6827, Bibcode:2014AJ....147...87T, doi:10.1088/0004-6256/147/4/87, S2CID 56066740, 87.