WASP-58
WASP-58 is a binary star system comprising a G-type main-sequence star and a red dwarf about 955 light-years away. WASP-58 is slightly depleted in heavy elements, having 80% of the solar abundance of iron.[5] WASP-58 is much older than the Sun at 12.80+0.20
−2.10 billion years.[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lyra |
| Right ascension | 18h 18m 48.2531s[1] |
| Declination | 45° 10′ 19.2592″[1] |
| Apparent magnitude (V) | 11.66[2] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | G2V[2] |
| Astrometry | |
| Radial velocity (Rv) | -28.708[1] km/s |
| Proper motion (μ) | RA: 32.579[1] mas/yr Dec.: 47.140[1] mas/yr |
| Parallax (π) | 3.4147 ± 0.0214[1] mas |
| Distance | 955 ± 6 ly (293 ± 2 pc) |
| Orbit[3] | |
| Primary | WASP-58A |
| Companion | WASP-58B |
| Semi-major axis (a) | 1.281±0.002" (384±64 AU) |
| Details[4] | |
| WASP-58A | |
| Mass | 0.940±0.100 M☉ |
| Radius | 1.17±0.13 R☉ |
| Surface gravity (log g) | 4.23±0.1[5] cgs |
| Temperature | 6039±55[5] K |
| Metallicity [Fe/H] | -0.09±0.04 dex |
| Rotation | 22.6+11.7 −6.1 d[6] |
| Rotational velocity (v sin i) | 2.8±0.9 km/s |
| Age | 12.80+0.20 −2.10 Gyr |
| WASP-58B | |
| Temperature | 3396±53[3] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
Lithium was detected in the stellar spectrum of WASP-58A, making the star anomalous for its advanced age.[2]
A multiplicity survey in 2015 did detect a red dwarf stellar companion[8] at a projected separation of 1.281±0.002″ to WASP-58A, and it was confirmed to be gravitationally bound in 2016.[3]
Planetary system
In 2012 a transiting hot Jupiter planet b was detected on a tight, circular orbit around the primary star WASP-58A.[2]
Planetary equilibrium temperature is 1270±80 K.[2]
| 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 |
References
- Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- WASP-52b, WASP-58b, WASP-59b, and WASP-60b: four new transiting close-in giant planets, 2012, arXiv:1211.0810
- FRIENDS OF HOT JUPITERS. IV. STELLAR COMPANIONS BEYOND 50 AU MIGHT FACILITATE GIANT PLANET FORMATION, BUT MOST ARE UNLIKELY TO CAUSE KOZAI-LIDOV MIGRATION, 2016, arXiv:1606.07102
- The GAPS Programme with HARPS-N at TNG. XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets, 2017, arXiv:1704.00373
- SWEET-Cat update and FASMAA new minimization procedure for stellar parameters using high-quality spectra, 2017, arXiv:1703.06671
- Discrepancies between isochrone fitting and gyrochronology for exoplanet host stars?, 2014, arXiv:1406.4402
- "WASP-58". SIMBAD. Centre de données astronomiques de Strasbourg.
- A Lucky Imaging search for stellar companions to transiting planet host stars, 2015, arXiv:1507.01938
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