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]

WASP-58

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 mas[1]
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
Gaia DR2 2115245554756763392, TYC 3525-76-1, 2MASS J18184825+4510192[7]
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]

The WASP-58 planetary system^[4]

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