WASP-59

WASP-59 is a K-type main-sequence star about 379 light-years away. The star's age is essentially unconstrained by observations. WASP-59 is slightly depleted in heavy elements, having 70% of the solar abundance of iron.^[2] The star produces extremely low levels of ultraviolet light, indicating an absence of flare activity.^[4]

WASP-59

Observation data Epoch J2000      Equinox J2000
Constellation	Pegasus
Right ascension	23h 18m 29.5475s[1]
Declination	24° 53′ 21.4364″[1]
Apparent magnitude (V)	12.78
Characteristics
Evolutionary stage	Main sequence
Spectral type	K5V
Astrometry
Radial velocity (Rv)	-56.82[1] km/s
Proper motion (μ)	RA: 33.729[1] mas/yr Dec.: −2.522[1] mas/yr
Parallax (π)	8.5968±0.0421 mas[1]
Distance	379 ± 2 ly (116.3 ± 0.6 pc)
Details[2]
Mass	0.719±0.035 M☉
Radius	0.613±0.044 R☉
Temperature	4650±150 K
Metallicity [Fe/H]	-0.15±0.11 dex
Rotational velocity (v sin i)	2.3±1.5 km/s
Age	7±7 Gyr
Other designations
Gaia DR2 2841043011433969152, 2MASS J23182955+2453214[3]
Database references
SIMBAD	data

A multiplicity survey in 2015 did not detect any stellar companions to WASP-59.^[5]

Planetary system

In 2012 a transiting hot Jupiter planet b was detected on a tight, mildly eccentric orbit.^[6]

Its equilibrium temperature is 670±35 K.^[6] The planet is unusually dense for a gas giant, representing an outlier on a mass-radius diagram.^[7]

The WASP-59 planetary system^[2]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	0.857+0.046 −0.047 MJ	0.0697±0.0011	7.919585±0.000010	0.101+0.046 −0.048	89.27±0.52°	0.775±0.068 RJ