About this world
HD 73583 b is a sub-Neptune orbiting HD 73583, an orange dwarf (type K4V) 103 light-years from Earth. It is about 2.8 times the size of Earth and holds 10 Earth masses. It completes an orbit every 6.4 days at 0.06 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 714 K (441 °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 2022 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction. HD 73583 has 2 known planets; the others are HD 73583 c.