WASP-96b

WASP-96b is a gas giant exoplanet. Its mass is 0.48 times that of Jupiter. It is 0.0453 AU from the class G star WASP-96, which it orbits every 3.4 days. It is about 1,140 light-years away from Earth, in the constellation Phoenix. It was discovered in 2013 by the Wide Angle Search for Planets (WASP).

WASP-96b

Spectrum of WASP-96b, taken by the James Webb Space Telescope
Discovery[1]
Discovered by	Hellier et al. (WASP)
Discovery date	October 2013
Detection method	Transit
Orbital characteristics[2]
Semi-major axis	0.0454±0.0013 AU
Eccentricity	<0.11
Orbital period (sidereal)	3.4252602(27) d
Inclination	85.60°±0.20°
Semi-amplitude	64.0+5.3 −4.8 m/s
Physical characteristics[2]
Mean radius	1.200±0.060 RJ
Mass	0.490+0.049 −0.047 MJ
Mean density	0.352+0.068 −0.059 g/cm3
Temperature	1285 K[1]

WASP-96b orbits its Sun-like star WASP-96 every 3.4 Earth days at a distance just one-ninth of the distance between Mercury and the Sun.^[3]

The hot-Jupiter exoplanet was found via the transiting method by Coel Hellier et.al. in 2013 as part of the WASP-South survey.^[1]

Atmosphere

WASP-96b's spectrum was one of the images featured in the initial science release from the James Webb Space Telescope in July 2022.^[4] The spectrum confirmed the presence of water, as well as providing evidence for "clouds and hazes" within the planet's atmosphere.^[3] Prior to this discovery, WASP-96b was thought to be free of clouds.^[5][6]

While the light curve released confirms properties of the planet that had already been determined from other observations – the existence, size, and orbit of the planet – the transmission spectrum revealed previously hidden details of the atmosphere: the unambiguous signature of water, indications of haze, and evidence of clouds that were suspected based on prior observations.^[7]

A study in 2023 measured the abundance of certain chemical species in the atmosphere of WASP-96b as seen in the table below.^[8] Models of the atmosphere with patchy clouds and hazes best describes the observations through the James Webb Space Telescope.^[8]

Chemical Species[8]	log(VMR)[8]	Concentration
Water vapor	-3.59+0.35 −0.35	257 ppm
Carbon monoxide	-3.25+0.91 −5.06	562 ppm
Carbon dioxide	-4.38+0.47 −0.57	41.7 ppm
Sodium	-6.85+2.48 −3.10	141 ppb
Potassium	-8.04+1.22 −1.71	9.12 ppb

See also

• Wide Angle Search for Planets
• List of exoplanets discovered in 2013