70 Ophiuchi
Star in the constellation Ophiuchus / From Wikipedia, the free encyclopedia
This article is about p Ophiuchi. Not to be confused with ρ (Rho) Ophiuchi.
70 Ophiuchi is a binary star system located 16.6 light years away from the Earth. It is in the constellation Ophiuchus. At magnitude 4 it appears as a dim star visible to the unaided eye away from city lights.
Quick Facts Observation data Epoch J2000 Equinox, Apparent magnitude (V) ...
Observation data Epoch J2000 Equinox | |
---|---|
Constellation | Ophiuchus |
70 Ophiuchi | |
Right ascension | 18h 05m 27.285s[1] |
Declination | +02° 29′ 00.36″[1] |
Apparent magnitude (V) | 4.00 - 4.03[2] |
A | |
Right ascension | 18h 05m 27.371s[3] |
Declination | +02° 29′ 59.32″[3] |
Apparent magnitude (V) | 4.13[3] |
B | |
Right ascension | 18h 05m 27.462s[4] |
Declination | +02° 29′ 56.22″[4] |
Apparent magnitude (V) | 6.07[3] |
Characteristics | |
Spectral type | K0V + K4V[5] |
Apparent magnitude (B) | 4.97/7.26[3] |
Apparent magnitude (R) | 3.6/5.6[3] |
U−B color index | +0.69[6] |
B−V color index | +0.84/+1.19[3] |
Variable type | BY Dra[7] or RS CVn[2] |
Astrometry | |
70 Oph A | |
Radial velocity (Rv) | −6.87[8] km/s |
Proper motion (μ) | RA: 206.525±0.246[9] mas/yr Dec.: −1107.492±0.164[9] mas/yr |
Parallax (π) | 195.5674 ± 0.1964 mas[9] |
Distance | 16.68 ± 0.02 ly (5.113 ± 0.005 pc) |
Absolute magnitude (MV) | +5.49[10] |
70 Oph B | |
Proper motion (μ) | RA: 333.292±0.264[11] mas/yr Dec.: −1068.354±0.215[11] mas/yr |
Parallax (π) | 195.2166 ± 0.1012 mas[12] |
Distance | 16.707 ± 0.009 ly (5.123 ± 0.003 pc) |
Orbit[8] | |
Period (P) | 88.38±0.017 yr |
Semi-major axis (a) | 4.554±0.0052″ |
Eccentricity (e) | 0.4992±0.00039 |
Inclination (i) | 121.16±0.078° |
Longitude of the node (Ω) | 302.12±0.097° |
Periastron epoch (T) | 1895.94 |
Argument of periastron (ω) (secondary) | 14.0±0.14° |
Details | |
70 Oph A | |
Mass | 0.90 ± 0.04[13] M☉ |
Radius | 0.91 ± 0.03[14] R☉ |
Luminosity (bolometric) | 0.59 ± 0.02[14] L☉ |
Surface gravity (log g) | 4.5[15] cgs |
Temperature | 5,300[15] K |
Metallicity [Fe/H] | +0.04[16] dex |
Rotation | 19.7 days[16] |
Age | 1.9[17] Gyr |
70 Oph B | |
Mass | 0.70 ± 0.07[13] M☉ |
Luminosity (bolometric) | 0.13 ± 0.03[13] L☉ |
Temperature | 4,350 ± 150[13] K |
Other designations | |
70 Oph A: LHS 458 | |
70 Oph B: LHS 459 | |
Database references | |
SIMBAD | The system |
A | |
B | |
Exoplanet Archive | data |
ARICNS | data |
Location of 70 Ophiuchi in the constellation Ophiuchus |
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