BD+05 4868
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Pegasus |
| BD+05 4868A | |
| Right ascension | 21h 47m 26.52s |
| Declination | +06° 36′ 17.5″ |
| Apparent magnitude (V) | 10.16 |
| BD+05 4868B | |
| Right ascension | 21h 47m 26.71s |
| Declination | +06° 36′ 18.4″ |
| Characteristics | |
| Evolutionary stage | main-sequence star |
| Spectral type | mid-K+M |
| Astrometry | |
| BD+05 4868A | |
| Radial velocity (Rv) | −25.56±0.15 km/s |
| Proper motion (μ) | RA: 205.593±0.017 mas/yr Dec.: 106.359±0.012 mas/yr |
| Parallax (π) | 22.9322±0.0163 mas |
| Distance | 142.2 ± 0.1 ly (43.61 ± 0.03 pc) |
| BD+05 4868B | |
| Radial velocity (Rv) | 24.62±1.60 km/s |
| Proper motion (μ) | RA: 212.158±0.064 mas/yr Dec.: 112.173±0.049 mas/yr |
| Parallax (π) | 23.1585 ± 0.0629 mas |
| Distance | 140.8 ± 0.4 ly (43.2 ± 0.1 pc) |
| Details | |
| BD+05 4868A | |
| Mass | 0.70±0.02 M☉ |
| Radius | 0.69±0.02 R☉ |
| Luminosity | 0.192±0.005 L☉ |
| Surface gravity (log g) | 4.60+0.03 −0.02 cgs |
| Temperature | 4,540±110 K |
| Metallicity [Fe/H] | −0.07±0.09 dex |
| Age | 11.1+1.7 −3.0 Gyr |
| BD+05 4868B | |
| Mass | 0.43±0.03 M☉ |
| Radius | 0.42±0.02 R☉ |
| Luminosity | 0.023±0.001 L☉ |
| Surface gravity (log g) | 4.83±0.03 cgs |
| Temperature | 3,480±70 K |
| Position (relative to BD+05 4868A) | |
| Component | BD+05 4868B |
| Epoch of observation | October 2024 |
| Angular distance | 3″ |
| Projected separation | 132.037±0.002 AU |
| Other designations | |
| BD+05 4868A: HIP 107587, G 93-37, LSPM J2147+0636, LTT 18540, 2MASS J21472654+0636178, TIC 466376085, TYC 556-856-1, UCAC2 34205672, WISE J214726.69+063618.9, Gaia DR3 2700378125204437760 | |
| BD+05 4868B: Gaia DR3 2700378125203895808 | |
| Database references | |
| BD+05 4868A | |
| SIMBAD | data |
| BD+05 4868B | |
| SIMBAD | data |
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BD+05 4868 is a binary star consisting of a K-dwarf and an M-dwarf. It is notable for a planetary companion around the primary star. This planet, named BD+05 4868Ab, orbits the star so close that it has begun to disintegrate, creating a large comet-like tail which can be seen in transits.
BD+05 4868 was first cataloged in the Bonner Durchmusterung and in 1961 the star was identified as a proper motion star by Giclas et al. In 1984 its spectrum was observed for the first time, identifying it as a K5: type star. The star was first identified as a binary from Gaia data. The common proper motion and parallax indicate that the pair is physically bound. The binary was also detected with the Las Cumbres Observatory Global Telescope (LCOGT) 2 m Faulkes Telescope North and with Keck NIRC2.