93 Leonis
93 Leonis (93 Leo) is a binary star in the constellation Leo. Its apparent magnitude is 4.522.[2] Based on the system's parallax, 93 Leonis is located about 233 light-years (71 parsecs) away.[1]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 47m 59.13595s[1] |
| Declination | +20° 13′ 08.1500″[1] |
| Apparent magnitude (V) | 4.522[2] |
| Characteristics | |
| Spectral type | G5III + A7V[3] |
| U−B color index | +0.28[4] |
| B−V color index | +0.9 / +0.2[3] |
| Variable type | RS CVn[5] |
| Astrometry | |
| Radial velocity (Rv) | 0.750 ± 0.05[6] km/s |
| Proper motion (μ) | RA: -145.49[1] mas/yr Dec.: -4.34[1] mas/yr |
| Parallax (π) | 14.02 ± 0.23[1] mas |
| Distance | 233 ± 4 ly (71 ± 1 pc) |
| Absolute bolometric magnitude (Mbol) | 0.48 / 1.27[3] |
| Orbit[3] | |
| Period (P) | 71.69 d |
| Semi-major axis (a) | 7.5 ± 0.1 mas |
| Eccentricity (e) | 0 |
| Inclination (i) | 50.1 ± 0.5° |
| Longitude of the node (Ω) | 138 ± 1° |
| Periastron epoch (T) | JD 2447642.6 ± 0.2 |
| Argument of periastron (ω) (secondary) | 0° |
| Semi-amplitude (K1) (primary) | 29.67 ± 0.29 km/s |
| Semi-amplitude (K2) (secondary) | 33.8 ± 2.1 km/s |
| Details[3] | |
| 93 Leo A | |
| Mass | 2.25 ± 0.29 M☉ |
| Radius | 9.1 ± 0.5 R☉ |
| Luminosity | 49.4 ± 3.4 L☉ |
| Temperature | 5100 ± 100 K |
| 93 Leo B | |
| Mass | 1.97 ± 0.15 M☉ |
| Radius | 2.7 ± 0.2 R☉ |
| Luminosity | 23.9 ± 1.9 L☉ |
| Temperature | 7800 ± 200 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
93 Leonis is a double-lined spectroscopic binary. Two components are known to exist, because their spectral lines shift periodically, due to the Doppler effect. The two stars are a G-type red giant and an A-type main-sequence star.[3] They complete an orbit once every 71.69 days. The system is also known to be an RS Canum Venaticorum variable, due to its binarity.[5] For that reason, it has been given the variable star designation DQ Leonis.[5]
In Chinese astronomy, 93 Leonis is called 太子, Pinyin: Tàizǐ, meaning Crown Prince, because this star is marking itself and stand alone in Crown Prince asterism, Supreme Palace enclosure mansion (see : Chinese constellation).[7]
References
- van Leeuwen, F.; et al. (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.
- Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
- Hummel, C. A.; et al. (July 1995). "Orbits of Small Angular Scale Binaries Resolved with the Mark III Interferometer". Astronomical Journal. 110: 376. Bibcode:1995AJ....110..376H. doi:10.1086/117528.
- Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- "* 93 Leo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 15 July 2017.
- Halbwachs, J.-L.; Mayor, M.; Udry, S. (2012). "Double stars with wide separations in the AGK3 - I. Components that are themselves spectroscopic binaries". Monthly Notices of the Royal Astronomical Society. 422 (1): 14–24. Bibcode:2012MNRAS.422...14H. doi:10.1111/j.1365-2966.2012.20308.x.
- Ian Ridpath's Startales - Leo the Lion