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XO-6b

Hot Jupiter exoplanet orbiting the star XO-6

XO-6

Jupiter compared to XO-6b
Discovery[1]
Discovery site	Haleakalā ObservatoryinMaui, Hawaii
Discovery date	December 8th, 2016
Detection method	Tranist
Orbital characteristics[1]
Semi-major axis	0.0815±0.0077 AU
Eccentricity	0.00 (fixed)
Orbital period (sidereal)	3.7649939±0.0000013 d
Inclination	86.0°±0.2°
Time of periastron	2,458,843.93943±0.00012 JD
Semi-amplitude	<450 m/s
Physical characteristics[1]
Mean radius	2.07±0.22 RJ
Mass	1.9±0.5 MJ or <4.4 MJ
Mean density	270 ± 110 kg/m3 (460 ± 190 lb/cu yd) or <620 kg/m3 (1,050 lb/cu yd)
Temperature	1,577±28 K

XO-6b is a transiting exoplanet, a hot Jupiter, orbiting the star XO-6 around 760 Light Years (230 Parsecs) away from Earth. It was discovered in 2016 by the XO planet search team.^[2][3]

XO-6b is one of the puffiest planets ever discovered, with a maximum mass of 4.4 times of Jupiter. It is over twice as wide, making it one of the largest exoplanets ever found (see list of largest exoplanets). Later estimates, however, make it around two times the mass of Jupiter.^[2][3]

XO-6b has a tight orbit, which means a year on it is only about 4 days. XO-6 is slightly more than one tenth as far from its host star as Mercury is to the sun.

XO-6b orbits XO-6, a faint 10th magnitude star in the constellation Camelopardalis.^[4] Due to its magnitude, this star is too faint to be seen with the naked eye, but can be seen with a telescope.^{[citation needed]} XO-6 is a F-type main-sequence star with about 1.5 times the mass of the Sun. It is also radiating 4 times as bright, and is almost twice the size of the Sun. It is also hotter, with a temperature of 6720 kelvins, which gives it the typical hue of an F-type star.^[2] Unlike most other stars of its kind, XO-6 rotates rapidly at a rate of 43 km/s.

• Garai, Zoltán; et al. (January 2020). "Periodic transit timing variations and refined system parameters of the exoplanet XO-6b". Monthly Notices of the Royal Astronomical Society. 491 (2): 2760–2769. arXiv:1911.07054. Bibcode:2020MNRAS.491.2760G. doi:10.1093/mnras/stz3235.
• Ridden-Harper, Andrew; Turner, Jake D.; Jayawardhana, Ray (December 2020). "TESS Observations of the Hot Jupiter Exoplanet XO-6b: No Evidence of Transit Timing Variations". The Astronomical Journal. 160 (6): 249. arXiv:2009.10781. Bibcode:2020AJ....160..249R. doi:10.3847/1538-3881/abba1e. S2CID 221856652.