About this world
TOI-5789 d is a super-Earth orbiting TOI-5789, an orange dwarf (type K1V) 66.7 light-years from Earth. It is about 1.9 times the size of Earth (its size estimated from its mass), with at least 4.3 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 29.6 days at 0.18 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 545 K (272 °C): far too hot for liquid water on its surface. By the "cosmic shoreline", its star has probably stripped its atmosphere away, leaving bare rock.
It was discovered in 2026 by radial velocity with Multiple Observatories. The star wobbles toward and away from us, Doppler-shifting its spectrum. TOI-5789 has 4 known planets; the others are TOI-5789 b, TOI-5789 c and TOI-5789 e.