HD 169830
F-type star in the constellation Sagittarius
From Wikipedia, the free encyclopedia
HD 169830 is a star in the southern constellation of Sagittarius. It has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of +5.90.[2] The star is located at a distance of 120 light-years from the Sun based on parallax. It is drifting closer with a radial velocity of −17.3 km/s,[4] and is predicted to come as close as 20.7 ly (6.4 pc) in 2.08 million years.[10] HD 169830 is known to be orbited by two large Jupiter-like exoplanets.
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 18h 27m 49.48500s[1] |
| Declination | –29° 49′ 00.7008″[1] |
| Apparent magnitude (V) | +5.90[2] |
| Characteristics | |
| Spectral type | F7V[3] |
| B−V color index | 0.517±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | −17.271±0.0004[4] km/s |
| Proper motion (μ) | RA: −0.341[1] mas/yr Dec.: +16.103[1] mas/yr |
| Parallax (π) | 27.1461±0.1469 mas[1] |
| Distance | 120.1 ± 0.7 ly (36.8 ± 0.2 pc) |
| Absolute magnitude (MV) | +3.08[2] |
| Details[5] | |
| Mass | 1.4 M☉ |
| Radius | 1.84 R☉ |
| Luminosity | 4.63[6] L☉ |
| Surface gravity (log g) | 4.06 cgs |
| Temperature | 6,300±50[6] K |
| Metallicity [Fe/H] | 0.15 dex |
| Rotation | 8.3 d[7] |
| Rotational velocity (v sin i) | 3.83 km/s |
| Age | 4.95[8] Gyr |
| Other designations | |
| CD−29°14965, GC 25175, HD 169830, HIP 90485, HR 6907, SAO 186838, GSC 06869-01277, 2MASS J18274949-2949007, Gaia DR2 4048037707717866880[9] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
This is an F-type main-sequence star[6] with a stellar classification of F7V.[3] It is 3.83[8] billion years old and chromospherically inactive[8] with a slow rotation rate,[8] having a projected rotational velocity of 3.83 km/s.[5] This star is 40% more massive and 84% larger than the Sun. Combining the mass and radius makes the surface gravity only 41% that of the Sun. It is radiating 4.6[6] times the luminosity of the Sun from its photosphere at an effective temperature of 6,300 K.[6]
A candidate stellar companion, designated component B, lies at an angular separation of 11″ along a position angle of 265°.[11]
Planetary system
On April 15, 2000, the Geneva Extrasolar Planet Search Team announced the discovery of a minimum mass 3 MJ planet in a 226-day orbit.[12][6] Three years later on June 30, 2003, the same team, using the same method, discovered a minimum mass 3.5 MJ second planet orbiting the star.[7] In 2022, the inclination and true mass of HD 169830 c were measured via astrometry.[13]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥2.956+0.070 −0.069 MJ |
0.8130+0.0083 −0.0084 |
225.789+0.074 −0.081 |
0.306+0.012 −0.013 |
— | — |
| c | 7.669+1.937 −2.755 MJ |
3.075+0.132 −0.146 |
1818.8+5.7 −6.4 |
0.246+0.022 −0.018 |
24.469+12.739 −7.205° |
— |