An international team of astronomers has discovered the hottest exoplanet. A related study was published in the journal Nature.
The temperature of the side of the atmosphere of hot Jupiter KELT-9b (HD 195689 b) facing the luminary is 4.6 thousand kelvin (about 4327 degrees Celsius, like an orange dwarf). The conditions in the gas shell of a celestial body are such that, most likely, there are no molecules in it (matter is in an atomic or ionized state).
The exoplanet revolves around the parent star KELT-9 (HD 195689) with a period of 1.48 days and at a distance of 0.03 astronomical units. The celestial body is about 2.88 times heavier and 6.75 times larger than Jupiter.
The star KELT-9 is about 2.5 times heavier and 13.14 times larger than the Sun. The effective surface temperature of the star is 10.17 thousand Kelvin (the Sun is about 5.8 thousand Kelvin); in the spectral classification, the celestial body is located between the stars of types A and B.
The KELT-9 system was studied by the KELT observatories (Kilodegree Extremely Little Telescope).
Previously, the hottest exoplanet was WASP-33 b (HD 15082 b), the effective surface temperature of which is estimated at 3.3 thousand Kelvin. According to a new study, KELT-9b receives 700 times more X-ray radiation from its star than WASP-33 b.