RA 289.2277° · Dec 5.1632° · exoplanet
16 more points to reach Epic.
HD 180617 b is a rare exoplanet. It lies about 19.3 light-years from Earth, shines at apparent magnitude 9.12, has spectral type M2.5 V and has an equilibrium temperature near 202 K.
Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.
At apparent magnitude 9.12, a small backyard telescope will bring it into view.
Like any astronomical target, HD 180617 b 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 180617 b scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.
That score comes from 4 science badges — Confirmed exoplanet, Nearby (<25 ly), Sub-Neptune and Two suns in its sky — 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.