About this world
HD 15337 c is a sub-Neptune orbiting HD 15337, an orange dwarf (type K1V) 146 light-years from Earth. It is about 2.5 times the size of Earth and holds 6.8 Earth masses. It completes an orbit every 17.2 days at 0.12 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 656 K (383 °C): far too hot for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium. Its atmosphere has already been studied: 6 spectroscopic observations, 2 of them with the James Webb Space Telescope.
It was discovered in 2019 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction. HD 15337 has 2 known planets; the others are HD 15337 b.