About this world
HD 148797 b is a Neptune-like planet orbiting HD 148797, a yellow-white F-type star (type F6) 562 light-years from Earth. It is about 0.74 times the size of Jupiter and holds 0.12 Jupiter masses. It completes an orbit every 42.1 days at 0.26 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 762 K (489 °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. HD 148797 has 2 known planets; the others are HD 148797 c.