About this world
TOI-1839 c is a sub-Neptune orbiting TOI-1839, a yellow, Sun-like star (type G9V) 379 light-years from Earth. It is about 2.5 times the size of Earth and holds 6 Earth masses. It completes an orbit every 4.02 days at 0.047 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 1,121 K (848 °C): far too hot for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2026 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction. TOI-1839 has 2 known planets; the others are TOI-1839 b.