88 Leonis is a wide binary[5] star system in the equatorial constellation of Leo, the lion. The system is near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.27.[2] It is located at a distance of 77 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −4.8 km/s.[2] It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.379 arc seconds per annum.[11]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 31m 44.94461s[1] |
| Declination | +14° 21′ 52.2131″[1] |
| Apparent magnitude (V) | 6.27[2] + 9.22[3] |
| Characteristics | |
| Spectral type | F9.5V[4] + G5[3] |
| B−V color index | 0.570[2] |
| Astrometry | |
| Radial velocity (Rv) | −4.81±0.09[2] km/s |
| Proper motion (μ) | RA: −330.279[1] mas/yr Dec.: −190.081[1] mas/yr |
| Parallax (π) | 42.2619 ± 0.0812 mas[1] |
| Distance | 77.2 ± 0.1 ly (23.66 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.46[2] |
| Details | |
| 88 Leo A | |
| Mass | 1.06[5] M☉ |
| Radius | 1.10+0.03 −0.05[1] R☉ |
| Luminosity | 1.470±0.004[1] L☉ |
| Surface gravity (log g) | 4.25[6] cgs |
| Temperature | 6,060+140 −76[1] K |
| Metallicity [Fe/H] | −0.06±0.02[2] dex |
| Rotation | 14.32 days[7] |
| Age | 5.7+1.6 −3.1[2] Gyr |
| 88 Leo B | |
| Mass | 0.74[8] M☉ |
| Other designations | |
| 88 Leo A: AG+14°1209, GJ 3669, SAO 99648, LTT 13145[9] | |
| 88 Leo B: AG+14°1208, GJ 3670, SAO 99647, LTT 13146[10] | |
| Database references | |
| SIMBAD | data |
The primary member of the system, component A, is a yellow-white hued F-type main-sequence star with a stellar classification of F9.5V.[4] It is an estimated 5.7[2] billion years old and is spinning with a rotation period of 14.3 days.[7] The star has a short magnetic activity cycle that averages around 3.5 years. A second cycle appears to vary over time, lasting 13.7 years at the start of observations then decreasing to 8.6 years over a span of 34 years of measurement.[7] The star has 1.06[5] times the mass of the Sun and 1.10[1] times the Sun's radius. It is radiating 1.47[1] times the luminosity of the Sun from its photosphere at an effective temperature of 6,060 K.[1]
The secondary, component B, is a magnitude 9.22[3] star at an angular separation of 15.46″ from the primary along a position angle of 326°.[8] It has a class of G5[3] and 74% of the Sun's mass. The pair share a common proper motion through space with a projected separation of 360.6 AU.[8]
References edit
- ^ a b c d e f g h i j k 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.
- ^ a b c d e f g h i 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 Halbwachs, J. -L.; et al. (2017), "Double stars with wide separations in the AGK3 - II. The wide binaries and the multiple systems", Monthly Notices of the Royal Astronomical Society, 464 (4): 4966, arXiv:1610.04423, Bibcode:2017MNRAS.464.4966H, doi:10.1093/mnras/stw2683.
- ^ a b Gray, R. O.; et al. (2006), "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ a b c Halbwachs, J. -L; et al. (2018), "Multiplicity among solar-type stars. IV. The CORAVEL radial velocities and the spectroscopic orbits of nearby K dwarfs", Astronomy and Astrophysics, 619: A81, arXiv:1808.04605, Bibcode:2018A&A...619A..81H, doi:10.1051/0004-6361/201833377, S2CID 119437322
- ^ Hinkel, Natalie R.; et al. (October 2017), "A Catalog of Stellar Unified Properties (CATSUP) for 951 FGK-Stars within 30 pc", The Astrophysical Journal, 848 (1): 19, arXiv:1709.04465, Bibcode:2017ApJ...848...34H, doi:10.3847/1538-4357/aa8b0f, S2CID 118941011, 34.
- ^ a b c Oláh, K.; et al. (July 2009), "Multiple and changing cycles of active stars. II. Results", Astronomy and Astrophysics, 501 (2): 703–713, arXiv:0904.1747, Bibcode:2009A&A...501..703O, doi:10.1051/0004-6361/200811304, S2CID 15498919.
- ^ a b c Tokovinin, A.; Kiyaeva, O. (February 2016), "Eccentricity distribution of wide binaries", Monthly Notices of the Royal Astronomical Society, 456 (2): 2070–2079, arXiv:1512.00278, Bibcode:2016MNRAS.456.2070T, doi:10.1093/mnras/stv2825.
- ^ a b "88 Leo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-05.
- ^ "88 Leo B". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-05.
- ^ Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)", The Astronomical Journal, 129 (3): 1483–1522, arXiv:astro-ph/0412070, Bibcode:2005AJ....129.1483L, doi:10.1086/427854, S2CID 2603568.