61 Leonis
Binary star in the constellation Leo
From Wikipedia, the free encyclopedia
61 Leonis is a possible binary star[10] system in the zodiac constellation of Leo. It is faintly visible to the naked eye, having an apparent visual magnitude of 4.73.[1] The star is moving closer to the Sun with a heliocentric radial velocity of −12.7 km/s.[6] It is located roughly 580 light-years from the Sun, as determined from its annual parallax shift of 5.58 mas.[2]
 | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo[1] |
| Right ascension | 11h 01m 49.67462s[2] |
| Declination | −02° 29′ 04.5007″[2] |
| Apparent magnitude (V) | 4.73[1] |
| Characteristics | |
| Evolutionary stage | AGB[3] |
| Spectral type | M0 III[4] |
| B−V color index | +1.593±0.059[1] |
| Variable type | suspected[5] |
| Astrometry | |
| Radial velocity (Rv) | −12.7±0.3[6] km/s |
| Proper motion (μ) | RA: +9.76[2] mas/yr Dec.: −35.56[2] mas/yr |
| Parallax (π) | 5.58±0.24 mas[2] |
| Distance | 580 ± 30 ly (179 ± 8 pc) |
| Absolute magnitude (MV) | −1.53[1] |
| Details | |
| Radius | 74.5[7] R☉ |
| Luminosity | 1,377.86[1] L☉ |
| Surface gravity (log g) | 1.25±0.23[8] cgs |
| Temperature | 3,864±30[8] K |
| Metallicity [Fe/H] | 0.07±0.07[8] dex |
| Other designations | |
| p2 Leo, 61 Leo, NSV 5059, BD−01°2471, FK5 2879, HD 95578, HIP 53907, HR 4299, SAO 137947[9] | |
| Database references | |
| SIMBAD | data |
This is an evolved red giant star with a stellar classification of M0 III[4] that Eggen (1992) listed as being on the asymptotic giant branch (AGB).[3] It is a marginal barium star, showing an enhanced abundance of s-process elements in its outer atmosphere. This material may have been acquired during a previous mass transfer from a now white dwarf companion, or self-enriched by a dredge-up during the AGB process.[11] The measured angular diameter after correctly for limb darkening is 3.87±0.04 mas,[12] which, at the estimated distance of this system yields a physical size of about 74.5 times the radius of the Sun.[7]
61 Leonis is a suspected variable star with apparent magnitude changing between 4.69 and 4.79.[5] The variability was reported in a 1966 photometric survey, but has not been confirmed by more recent photometry.[13]
