About this world
TOI-1338 b is a Neptune-like planet orbiting TOI-1338 A, a yellow-white F-type star (type F8) 1.3 thousand light-years from Earth. It is about 0.68 times the size of Jupiter and holds 0.036 Jupiter masses. It completes an orbit every 95.4 days at 0.46 AU from its star.
Its equilibrium temperature is about 255 K (−18 °C), which places it in the conservative habitable zone: the band where liquid water could exist on a rocky surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium. Its atmosphere has already been studied: 3 spectroscopic observations, all of them with the James Webb Space Telescope.
It was discovered in 2020 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction. TOI-1338 A has 2 known planets; the others are TOI-1338 c.