93 Leonis
93 Leonis (93 Leo) is a binary star in the constellation Leo. Its apparent magnitude is 4.522.[3] Based on the system's parallax, 93 Leonis is located about 233 light-years (71 parsecs) away.[2]
A visual band light curve for DQ Leonis. The main plot shows the brightness variation over several years, and the inset plot shows the periodic variation seen during 1985. Adapted from Strassmeier et al. (1989)[1] | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 47m 59.13595s[2] |
| Declination | +20° 13′ 08.1500″[2] |
| Apparent magnitude (V) | 4.522[3] |
| Characteristics | |
| Spectral type | G5III + A7V[4] |
| U−B color index | +0.28[5] |
| B−V color index | +0.9 / +0.2[4] |
| Variable type | RS CVn[6] |
| Astrometry | |
| Radial velocity (Rv) | 0.750 ± 0.05[7] km/s |
| Proper motion (μ) | RA: −145.49[2] mas/yr Dec.: −4.34[2] mas/yr |
| Parallax (π) | 14.02 ± 0.23 mas[2] |
| Distance | 233 ± 4 ly (71 ± 1 pc) |
| Absolute bolometric magnitude (Mbol) | 0.48 / 1.27[4] |
| Orbit[4] | |
| 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[4] | |
| 93 Leo A | |
| Mass | 2.25±0.29 M☉ |
| Radius | 9.1±0.5 R☉ |
| Luminosity | 49.4±3.4 L☉ |
| Temperature | 5,100±100 K |
| 93 Leo B | |
| Mass | 1.97±0.15 M☉ |
| Radius | 2.7±0.2 R☉ |
| Luminosity | 23.9±1.9 L☉ |
| Temperature | 7,800±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.[4] 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.[6] For that reason, it has been given the variable star designation DQ Leonis.[6]
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).[8]
References
- ^ Strassmeier, Klaus G.; Hall, Douglas S.; Boyd, Louis J.; Genet, Russell M. (January 1989). "Photometric Variability in Chromospherically Active Stars. III. The Binary Stars". The Astrophysical Journal Supplement Series. 69: 141–215. Bibcode:1989ApJS...69..141S. doi:10.1086/191310. Retrieved 18 January 2022.
- ^ a b c d e f 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.
- ^ a b 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.
- ^ a b c d e f 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.
- ^ a b c d "* 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