About this world
HD 33142 d is a Neptune-like planet orbiting HD 33142, a giant star (type K0III) 396 light-years from Earth. It is about 0.83 times the size of Jupiter (its size estimated from its mass), with at least 0.2 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 89.9 days at 0.45 AU from its star.
Its equilibrium temperature is about 736 K (463 °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 radial velocity with Multiple Observatories. The star wobbles toward and away from us, Doppler-shifting its spectrum. HD 33142 has 3 known planets; the others are HD 33142 b and HD 33142 c.