20 Leonis Minoris is a binary star system in the northern constellation of Leo Minor. It is faintly visible to the naked eye, having an apparent visual magnitude of +5.4.[2] Based upon an annual parallax shift of 66.46 mas, it is located 49 light years from the Sun. The star has a relatively high proper motion[3] and is moving away from the Sun with a radial velocity of +56 km/s.[6] The system made its closest approach about 150,000 years ago when it came within 32.2 ly (9.86 pc).[13]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo Minor |
| Right ascension | 10h 01m 00.65765s[1] |
| Declination | +31° 55′ 25.2151″[1] |
| Apparent magnitude (V) | +5.40[2] |
| Characteristics | |
| Spectral type | G3 Va Hδ1[3] + M7 V[4] |
| U−B color index | +0.27[5] |
| B−V color index | +0.65[5] |
| Astrometry | |
| Radial velocity (Rv) | +55.96±0.09[6] km/s |
| Proper motion (μ) | RA: −527.63±0.30[1] mas/yr Dec.: −429.42±0.18[1] mas/yr |
| Parallax (π) | 66.46 ± 0.32 mas[1] |
| Distance | 49.1 ± 0.2 ly (15.05 ± 0.07 pc) |
| Absolute magnitude (MV) | 4.46[7] |
| Details | |
| 20 LMi A | |
| Mass | 1.12[8] M☉ |
| Radius | 1.247±0.021[9] R☉ |
| Luminosity | 1.378±0.027[9] L☉ |
| Temperature | 5,735±5.6[10] K |
| Rotation | 10.64±0.14 d[2] |
| Age | 6.2–7.7[11] Gyr |
| 20 LMi B | |
| Mass | 0.11[8] M☉ |
| Rotation | 19.2687 d[4] |
| Other designations | |
| Database references | |
| SIMBAD | data |
The primary member of this system is a G-type main-sequence star with a stellar classification of G3 Va Hδ1.[3] It has 12% more mass and a 25% larger radius than the Sun. The star is about seven[11] billion years old and is spinning with a rotation period of 10.6 days.[2] The small companion is an active red dwarf star that has a relatively high metallicity.[14] The two stars are currently separated by 14.5 arc seconds, corresponding to a projected separation of 2016 AU.[8]
In 2020, a candidate exoplanet was detected orbiting 20 Leonis Minoris (HD 86728). With a minimum mass of 0.032 MJ (10.2 ME) and an orbital period of 31 days, this would most likely be a hot Neptune.[15]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b (unconfirmed) | ≥0.032+0.005 −0.005 MJ | 0.2003+0.00007 −0.00007 | 31.15+0.02 −0.02 | 0.2+0.2 −0.1 | — | — |
References
External links
- "4C00774". ARICNS. Archived from the original on 2011-06-07. Retrieved 2006-07-31.