About this world
HD 153557 d is a gas giant orbiting HD 153557, an orange dwarf (type K0) 58.5 light-years from Earth. It is about 1.1 times the size of Jupiter (its size estimated from its mass) and holds 27 Jupiter masses. It completes an orbit every 111 years at 21 AU from its star.
Its equilibrium temperature is about 43 K (−230 °C): too cold 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 153557 has 3 known planets; the others are HD 153557 b and HD 153557 c.