K2-22b

K2-22b

Exoplanet		List of exoplanets Size comparison Neptune K2-22b
Parent star
Star		K2-22
Right ascension	(α)	11h17m55.88s
Declination	(δ)	+02d37m08.7s
Distance		733.852±163 ly (225±50 pc)
Mass	(m)	<0.60±0.07 M☉
Radius	(r)	<0.57±0.06 R☉
Temperature	(T)	3830±100 K
Metallicity	[Fe/H]	0.030±0.080
Physical characteristics
Mass	(m)	<445 M⊕
Radius	(r)	<2.5±0.4 R⊕
Density	(ρ)	<157.1 g/cm3 g cm−3
Temperature	(T)	2,100 K (1,830 °C; 3,320 °F)
Orbital elements
Semi-major axis	(a)	0.0088 AU
Eccentricity	(e)	null
Orbital period	(P)	0.381078 d
Inclination	(i)	null°
Discovery information
Discovery date		2015
Discoverer(s)
Discovery method		Transit
Discovery site		Kepler Space Observatory
Discovery status		Confirmed

K2-22b (also known as EPIC 201637175 b) is an exoplanet 734 ly from Earth, rapidly orbiting the red dwarf K2-22 with an orbital period of 9.145872 hours. It has an upper mass of 445 M_e and a radius of 2.5 R_e The planet was not detected in the K2 photometry. K2 photometry reveals the presence of an anomalous light curve consistent with evaporation of dust from the planet. This dust forms a tail both ahead and behind the planet, similar to some comets in the Solar system. The evaporation of this dust requires a low surface gravity from the host planet, implying it is a low mass, "Mars, Mercury, or even lunar sized bodies with surface gravities of 1/6 to 1/3 that of Earth are to be preferred."

The exoplanet is a hot Jupiter, and it orbits its host star very close. Its semi-major axis is among the smallest for hot Jupiters.

See also

• Astronomy portal

• List of exoplanet extremes

References

Preceded by PSR J1719-1438 b

Most dense 2015 —present

Succeeded by none