RA 42.8102° · Dec 60.3861° · star
15 more points to reach Epic.
HD 17520 is a rare star. It sits in the constellation Cas, shines at apparent magnitude 8.23 and has spectral type O9V.
Its spectrum reads O9V — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.
Look for HD 17520 in the constellation Cas. At apparent magnitude 8.23, it is an easy target for binoculars.
Like any astronomical target, HD 17520 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 17520 scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.
That score comes from 4 science badges — Star, Never sets (northern circumpolar), Blazing O-type star and Main-sequence 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.