RA 31.8905° · Dec 17.2026° · openngc
2 more points to reach Rare.
NGC 817 is an uncommon galaxy. It lies about 210,085,399.8 light-years from Earth, sits in the constellation Ari and shines at apparent magnitude 13.86.
A galaxy: a gravitationally bound city of stars, gas and dark matter, turning so slowly that a single rotation takes hundreds of millions of years.
Look for NGC 817 in the constellation Ari. At apparent magnitude 13.86, it takes a larger telescope or a long-exposure image to capture.
Like any astronomical target, NGC 817 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.
NGC 817 scores 32 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 2 points would lift it into a rarer tier.
That score comes from 5 science badges — Galaxy, Outside our galaxy entirely, Lenticular galaxy (a disc with no arms), On the zodiac and Faint fuzzy (mag > 13) — 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.