RA 302.0256° · Dec 66.8503° · exoplanet
14 more points to reach Epic.
HD 191939 d is a rare exoplanet. It lies about 174.8 light-years from Earth, shines at apparent magnitude 8.97, has spectral type G9 V and has an equilibrium temperature near 540 K.
It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
At apparent magnitude 8.97, it is an easy target for binoculars.
Like any astronomical target, HD 191939 d is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.
HD 191939 d scores 36 points on Spacedle's rarity scale, which places it in the rare tier. Another 14 points would lift it into a rarer tier.
That score comes from 5 science badges — Confirmed exoplanet, Sub-Neptune, Richly packed system, Found by TESS and Orbits a Sun-like star — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.