56 Pegasi
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Pegasus |
| Right ascension | 23h 07m 06.74364s |
| Declination | 25° 28′ 05.788″ |
| Apparent magnitude (V) | 4.74 |
| Characteristics | |
| Spectral type | K0.5II:Ba1CN-2CH-0.5 |
| U−B color index | +1.14 |
| B−V color index | +1.32 |
| Astrometry | |
| Radial velocity (Rv) | −27.55 km/s |
| Proper motion (μ) | RA: −4.288 mas/yr Dec.: −32.639 mas/yr |
| Parallax (π) | 6.1131±0.4108 mas |
| Distance | 530 ± 40 ly (160 ± 10 pc) |
| Absolute magnitude (MV) | −1.32 |
| Orbit | |
| Primary | 56 Peg A |
| Companion | 56 Peg B |
| Period (P) | 111.15±0.03 d |
| Semi-major axis (a) | 0.79+0.10 −0.08 AU |
| Eccentricity (e) | 0.072+0.048 −0.045 |
| Inclination (i) | 90+42 −41° |
| Longitude of the node (Ω) | 90+60 −42° |
| Periastron epoch (T) | 2455289+15 −85 HJD |
| Argument of periastron (ω) (secondary) | 55+270 −37° |
| Semi-amplitude (K1) (primary) | 1.47±0.04 km/s |
| Orbit | |
| Primary | 56 Peg A |
| Companion | 56 Peg C |
| Period (P) | 15,200+2,600 −1,600 d |
| Semi-major axis (a) | 22.1+3.6 −2.8 AU |
| Eccentricity (e) | 0.39+0.13 −0.12 |
| Inclination (i) | 157+4 −5° |
| Longitude of the node (Ω) | 153+14 −17° |
| Periastron epoch (T) | 2469014±2800 HJD |
| Argument of periastron (ω) (secondary) | 73+21 −24° |
| Details | |
| 56 Peg A | |
| Mass | 4.3±1.1 M☉ |
| Radius | 41 R☉ |
| Luminosity | 18.2 - 18.9 L☉ |
| Surface gravity (log g) | 0.50 cgs |
| Temperature | 4,185±85 K |
| Metallicity [Fe/H] | −0.21 dex |
| Rotational velocity (v sin i) | 4.4 km/s |
| Age | 100±100 Myr |
| 56 Peg B | |
| Mass | 0.13+0.06 −0.03 M☉ |
| 56 Peg C | |
| Mass | 0.85+0.25 −0.18 M☉ |
| Other designations | |
| 56 Peg, NSV 14429, BD+24°4716, FK5 3848, GC 32201, HD 218356, HIP 114155, HR 8796, SAO 91019, 2MASS J23070675+2528055 | |
| Database references | |
| SIMBAD | data |
56 Pegasi is a triple star system in the northern constellation of Pegasus. It is visible to the naked eye with a combined apparent visual magnitude of 4.74. The system is approximately 590 light years away from the Sun based on parallax, but is drifting closer with a radial velocity of −28 km/s. It is listed as a member of the Wolf 630 moving group.