HD 202908
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Apparentmagnitude(V)7.25±0.03[3]
Apparentmagnitude(V)8.87±0.14[3]
SpectraltypeG0 V (combined)[4]
U−B color index+0.07[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Equuleus[1] |
| A | |
| Right ascension | 21h 18m 34.85s[2] |
| Declination | +11° 34′ 08.2″[2] |
| Apparent magnitude (V) | 7.25±0.03[3] |
| B | |
| Right ascension | 21h 18m 34.80s[2] |
| Declination | +11° 34′ 08.0″[2] |
| Apparent magnitude (V) | 8.87±0.14[3] |
| Characteristics | |
| Spectral type | G0 V (combined)[4] |
| U−B color index | +0.07[5] |
| B−V color index | +0.56[5] |
| Aa | |
| Spectral type | F9 V[6] or G1 V[7] |
| Ab | |
| Spectral type | G0 V[6] or G2 V[7] |
| B | |
| Spectral type | G1.5 V[6] or G6 V[8] |
| Astrometry | |
| Radial velocity (Rv) | 6.24±0.04[9] km/s |
| Proper motion (μ) | RA: +29.213 mas/yr[10] Dec.: −49.564 mas/yr[10] |
| Parallax (π) | 19.3447±0.0543 mas[10] |
| Distance | 168.6 ± 0.5 ly (51.7 ± 0.1 pc) |
| A | |
| Absolute magnitude (MV) | +3.73±0.13[3] |
| B | |
| Absolute magnitude (MV) | +5.35±0.19[3] |
| Orbit[11] | |
| Primary | A |
| Companion | B |
| Period (P) | 28,685±173 d |
| Semi-major axis (a) | 0.5177±0.0046″ |
| Eccentricity (e) | 0.8651±0.0008 |
| Inclination (i) | 100.36±0.16° |
| Longitude of the node (Ω) | 255.03±0.17° |
| Periastron epoch (T) | 24,468,123±3 JD |
| Argument of periastron (ω) (secondary) | 171.9±0.3° |
| Semi-amplitude (K1) (primary) | 6.13±0.07 km/s |
| Semi-amplitude (K2) (secondary) | 13.95±0.09 km/s |
| Orbit[11] | |
| Primary | Aa |
| Companion | Ab |
| Period (P) | 3.9660465±0.0000015 d |
| Eccentricity (e) | 0.0033±0.0008 |
| Argument of periastron (ω) (secondary) | 271±13° |
| Semi-amplitude (K1) (primary) | 66.03±0.06 km/s |
| Semi-amplitude (K2) (secondary) | 69.69±0.06 km/s |
| Details | |
| The System | |
| Metallicity [Fe/H] | −0.04[12] dex |
| Age | 6.4±0.7[13] Gyr |
| The A Subystem | |
| Temperature | 6,100±150[14] K |
| Rotational velocity (v sin i) | 10[15] km/s |
| Aa | |
| Mass | 1.14[16] M☉ |
| Radius | 1.06±0.08[14] R☉ |
| Luminosity | 1.41+0.15 −0.14[14] L☉ |
| Ab | |
| Mass | 1.08[16] M☉ |
| Radius | 0.97±0.08[14] R☉ |
| Luminosity | 1.16+0.13 −0.11[14] L☉ |
| B | |
| Mass | 0.97[16] M☉ |
| Radius | 0.91±0.08[14] R☉ |
| Luminosity | 0.84+0.09 −0.08[14] L☉ |
| Temperature | 5,703±1,090[3] K |
| Rotational velocity (v sin i) | 9[15] km/s |
| Other designations | |
| AG+11°2644, BD+10°4514, GC 29812, HD 202908, HIP 105200, SAO 107015, ADS 14839AB, CCDM J21186+1134AB, WDS J21186+1134AB[17] | |
| Database references | |
| SIMBAD | data |
HD 202908, also known as HIP 105200, is a triple star located in the equatorial constellation Equuleus. It has an apparent magnitude of 7.01,[18] making it readily visible in binoculars but not to the naked eye. When resolved, the components have apparent magnitudes of 7.25 and 8.87 respectively.[3] The system is located relatively close at a distance of 169 light years based on Gaia DR3 parallax measurements[10] and it is receding with a heliocentric radial velocity of 6.24 km/s.[9]
