Khomsa

Khomsa is the only known planet of the sixth-magnitude star Chechia, catalogued as HD 192699, which lies in southeastern Aquila, near that constellation's border with Delphinus. Chechia is a yellow subgiant star some 238 light years from the Sun. It has a mass approximately 1.7 times greater than that of the Sun, and its evolution to the subgiant stage of its lifecycle has seen it expand to reach some five times the Sun's diameter.

Chechia's planet Khomsa is a massive gas giant, known to be at least twice as massive as Jupiter (and estimates place at it probably two and a half times Jupiter's mass). It follows an orbit around its star at a distance closely comparable with Earth's orbit around the Sun (with a semi-major axis of 1.063 AU, just a little greater than that of Earth).

Objects with more distant orbits typically have longer orbital periods, and so we might expect a 'year' for Khomsa to be slightly longer than a year on Earth, but because the star Chechia is considerably more massive than the Sun, an orbit for Khomsa in fact takes slightly less than a year on Earth, at 340 days and 23 hours. The star's subgiant nature means that its habitable zone lies rather farther from the star than that of the Sun, and Khomsa lies well within the inner boundary of this zone, meaning that the planet is too hot to sustain liquid water within its atmosphere.

The name Khomsa comes from IAU's international NameExoWorlds project, and was assigned by Tunisia. It comes from a traditional amulet, shaped in the form of an open hand, that is said to ward off misfortune.