TOI-5789 c is a sub-Neptune exoplanet with a radius of 2.86 Earth radii, part of a multi-planet system orbiting a bright K-dwarf star every 12.93 days. Located approximately 67 light-years away, the system includes at least four planets (b, c, d, e) with mutually inclined orbits exceeding 4 degrees, offering valuable insights into dynamic planetary formation processes uncommon in flat systems like our own. Discovered through TESS transits and confirmed via ground-based radial velocity and photometry, its close orbit results in high equilibrium temperatures, eliminating habitability prospects. However, the host star’s brightness (V=7.3 mag) makes TOI-5789 c ideal for atmospheric studies with instruments like JWST, potentially revealing hydrogen-rich envelopes, water vapor, or haze layers to better understand sub-Neptune evolution and composition.
