About this world
Kepler-174 d is a sub-Neptune orbiting Kepler-174, an orange dwarf 1.25 thousand light-years from Earth. It is about 2.2 times the size of Earth. It completes an orbit every 247 days at 0.68 AU from its star.
Its equilibrium temperature is about 212 K (−61 °C), which places it in the conservative habitable zone: the band where liquid water could exist on a rocky surface. By the "cosmic shoreline", it has likely held on to an atmosphere.
It was discovered in 2014 by transit with Kepler. A planet crosses its star and dims it by a tiny, periodic fraction. Kepler-174 has 3 known planets; the others are Kepler-174 b and Kepler-174 c.