WASP-45

WASP-45 is a K-type main-sequence star about 701 light-years (215 parsecs) away. The star's age cannot be well constrained, but it is probably older than the Sun. Yet WASP-45 is enriched in heavy elements compared to the Sun, having 240% of the solar abundance.^[5] WASP-45 has low ultraviolet emission, therefore it is suspected to have a low starspot activity,^[7] although chromospheric activity was reported elsewhere.^[4]

WASP-45

Observation data Epoch J2000      Equinox J2000
Constellation	Sculptor[1]
Right ascension	00h 20m 56.99413s[2]
Declination	−35° 59′ 53.7466″[2]
Apparent magnitude (V)	11.8[3]
Characteristics
Evolutionary stage	main sequence[2]
Spectral type	K2V[4]
Astrometry
Radial velocity (Rv)	4.71±0.33[2] km/s
Proper motion (μ)	RA: 52.831 mas/yr[2] Dec.: −46.940 mas/yr[2]
Parallax (π)	4.6520±0.0226 mas[2]
Distance	701 ± 3 ly (215 ± 1 pc)
Details[5]
Mass	0.932+0.045 −0.046 M☉
Radius	0.891±0.013 R☉
Luminosity	0.510±0.013 L☉
Surface gravity (log g)	4.508+0.023 −0.025 cgs
Temperature	5167±29 K
Metallicity [Fe/H]	0.388+0.090 −0.10 dex
Rotational velocity (v sin i)	2.3±0.7 km/s
Age	5.4+4.7 −3.5 Gyr
Other designations
TOI-229, TIC 120610833, WASP-45, TYC 6996-583-1, GSC 06996-00583, 2MASS J00205699-3559537[6]
Database references
SIMBAD	data
Exoplanet Archive	data

There is a companion star at a separation of 4.4 arcseconds, corresponding to 929 AU. The companion is estimated to have a mass of 0.157 M_☉ and a temperature of 3,154 K. Although it shares a similar distance and common proper motion with the primary star, its relative space velocity appears to be high enough that the pair are not gravitationally bound.^[8]

Planetary system

In 2011 a transiting hot Jupiter planet, WASP-45b, was detected.^[4] The planet equilibrium temperature is 1,170±24 K. No Rayleigh scattering was detected in the planetary atmosphere, implying the existence of hazes or a high cloud deck.^[9]

The WASP-45 planetary system^[9][5]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	1.018+0.046 −0.045 MJ	0.04089+0.00065 −0.00069	3.1260876(35)[10]	<0.043[10]	84.686±0.098°	0.978+0.026 −0.024 RJ