About this world
TOI-1408 c is a sub-Neptune orbiting TOI-1408, a yellow-white F-type star (type F8V) 455 light-years from Earth. It is about 2.2 times the size of Earth and holds 7.6 Earth masses. It completes an orbit every 2.17 days at 0.036 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 1,864 K (1,591 °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 timing variations with Transiting Exoplanet Survey Satellite (TESS). Pulsar, eclipse or transit timings drift as an unseen companion tugs on them. TOI-1408 has 2 known planets; the others are TOI-1408 b.