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| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lyra[1] |
| Right ascension | 18h 18m 48.25296s[2] |
| Declination | +45° 10′ 19.2603″[2] |
| Apparent magnitude (V) | 11.66[3] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | G2V[3] |
| Astrometry | |
| Radial velocity (Rv) | −28.42±0.71[2] km/s |
| Proper motion (μ) | RA: 32.658 mas/yr[2] Dec.: 47.057 mas/yr[2] |
| Parallax (π) | 3.3963±0.0112 mas[2] |
| Distance | 960 ± 3 ly (294.4 ± 1.0 pc) |
| Orbit[4] | |
| Primary | WASP-58A |
| Companion | WASP-58B |
| Semi-major axis (a) | 1.281±0.002" (384±64 AU) |
| Details[5] | |
| WASP-58A | |
| Mass | 0.940±0.100 M☉ |
| Radius | 1.17±0.13 R☉ |
| Surface gravity (log g) | 4.23±0.1[6] cgs |
| Temperature | 6039±55[6] K |
| Metallicity [Fe/H] | -0.09±0.04 dex |
| Rotation | 22.6+11.7 −6.1 d[7] |
| Rotational velocity (v sin i) | 2.8±0.9 km/s |
| Age | 12.80+0.20 −2.10 Gyr |
| WASP-58B | |
| Temperature | 3396±53[4] K |
| Other designations | |
| TOI-1627, TIC 424435940, WASP-58, TYC 3525-76-1, 2MASS J18184825+4510192[8] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
WASP-58 is a binary star system in the constellation Lyra. It comprises a G-type main-sequence star and a red dwarf at a separation of 384 astronomical units. WASP-58 is slightly depleted in heavy elements, having 80% of the solar abundance of iron. The system is much older than the Sun at 12.80+0.20
−2.10 billion years. Based on parallax measurements, it lies at a distance of 960 light-years (290 parsecs).
Lithium was detected in the stellar spectrum of WASP-58A, making the star anomalous for its advanced age.[3]
A multiplicity survey in 2015 detected a red dwarf stellar companion[9] at a projected separation of 1.281±0.002″ to WASP-58A, and it was confirmed to be gravitationally bound in 2016.[4]
In 2012 a transiting hot Jupiter planet, WASP-58b, was detected on a tight, circular orbit around the primary star WASP-58A.[3] The planetary equilibrium temperature is 1270±80 K.[3]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.899+0.074 −0.072 MJ |
0.0562+0.0019 −0.0020 |
5.017180±0.000011 | <0.044 | 87.4±1.5° | 1.37±0.2 RJ |