About this world
TOI-2458 b is a sub-Neptune orbiting TOI-2458, a yellow-white F-type star (type F9-F9.5) 368 light-years from Earth. It is about 2.8 times the size of Earth and holds 13 Earth masses. It completes an orbit every 3.74 days at 0.048 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 1,509 K (1,236 °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 2024 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction. TOI-2458 has 2 known planets; the others are TOI-2458 c.