XO-6b is a transiting

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, init ...

, a

hot Jupiter Hot Jupiters (sometimes called hot Saturns) are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods (). The close proximity to their stars and high surface-atmosphere temp ...

, orbiting the star XO-6 around 760

Light Years A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

(230

Parsec The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (au), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, and ...

s) away from Earth. It was discovered in 2016 by the XO planet search team.

Physical properties

XO-6b is one of the puffiest planets ever discovered, with a maximum mass of 4.4 times of Jupiter. It is up to twice as wide, making it one of the largest exoplanets ever found (see

list of largest exoplanets Below is a list of the largest exoplanets so far discovered, in terms of physical size, ordered by radius. Caveats This list of extrasolar objects may and will change over time because of inconsistency between journals, different methods used ...

). Later estimates, however, make it around two times the mass of Jupiter. XO-6b has a tight orbit, which means a

year A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hou ...

on it is only about 4 days. XO-6 is slightly more than one tenth as far from its host star as

Mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

is to the sun.

XO-6

XO-6b orbits XO-6, a faint 10th magnitude star in the constellation

Camelopardalis Camelopardalis is a large but faint constellation of the northern sky representing a giraffe. The constellation was introduced in 1612 or 1613 by Petrus Plancius. Some older astronomy books give Camelopardalus or Camelopardus as alternative for ...

. Due to its magnitude, this star is too faint to be seen with the naked eye, but can be seen with a telescope. XO-6 is a

F-type main-sequence star An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII ...

with about 1.5 times the mass of the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

. 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

kelvin The kelvin, symbol K, is the primary unit of temperature in the International System of Units (SI), used alongside its prefixed forms and the degree Celsius. It is named after the Belfast-born and University of Glasgow-based engineer and phys ...

s, which gives it the typical hue of an F-type star. Unlike most other stars of its kind, XO-6 rotates rapidly at a rate of 43 km/s.

Physical properties

XO-6

References

Further reading