Xi Pegasi
Double star in the constellation Pegasus
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Xi Pegasi (ξ Peg, ξ Pegasi) is the Bayer designation for a double star in the northern constellation of Pegasus, the winged horse. Located in the horse's neck, the primary component is an F-type main sequence star that is visible to the naked eye with an apparent visual magnitude of 4.2.[2] It is 87% larger and 15% more massive that the Sun, radiating 4.55 times the solar luminosity.[8] Based upon parallax measurements taken with the Hipparcos spacecraft, it is located 53.2 ± 0.2 light years from the Sun.[1]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Pegasus |
| Right ascension | 22h 46m 41.58118s[1] |
| Declination | +12° 10′ 22.3854″[1] |
| Apparent magnitude (V) | 4.195[2] + 11.70[3] |
| Characteristics | |
| Spectral type | F6V[4] + M3.5[5] |
| U−B color index | −0.015[2] |
| B−V color index | +0.502[2] |
| Astrometry | |
| Radial velocity (Rv) | −5.3[6] km/s |
| Proper motion (μ) | RA: +234.18[1] mas/yr Dec.: −493.29[1] mas/yr |
| Parallax (π) | 61.36±0.19 mas[1] |
| Distance | 53.2 ± 0.2 ly (16.30 ± 0.05 pc) |
| Absolute magnitude (MV) | 3.25[7] |
| Details | |
| Xi Peg A | |
| Mass | 1.16+0.07 −0.05[8] M☉ |
| Radius | 1.87±0.04[8] R☉ |
| Luminosity | 4.55+0.26 −0.25[8] L☉ |
| Surface gravity (log g) | 3.97±0.07[9] cgs |
| Temperature | 6,155+60 −53[8] K |
| Metallicity [Fe/H] | −0.27±0.03[9] dex |
| Rotational velocity (v sin i) | 12.67[10] km/s |
| Age | 5.0±0.5[9] Gyr |
| Xi Peg B | |
| Mass | 0.32[11] M☉ |
| Temperature | 3,569[3] K |
| Metallicity [Fe/H] | −0.25[3] dex |
| Other designations | |
| 46 Peg, Gl 872, BD+11°4875, HD 215648, HIP 112447, HR 8665, SAO 108165.[12] | |
| Database references | |
| SIMBAD | data |
The primary has been examined for the presence of an infrared excess that might indicate the presence of a debris disk, but none has been discovered.[13] The common proper motion companion, NLTT 54820, is a twelfth magnitude red dwarf located at an angular separation of 11.4″ along a position angle of 96.9°.[14] This corresponds to a projected physical separation of 192.3 AU.[13]