RA 201.3062° · Dec 54.9880° · star
4 more points to reach Rare.
Alcor is an uncommon star. It lies about 81.7 light-years from Earth, sits in the constellation UMa, shines at apparent magnitude 3.99 and has spectral type A5V SB.
Its spectrum reads A5V SB — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.
Look for Alcor in the constellation UMa. At apparent magnitude 3.99, it can be glimpsed with the unaided eye under dark skies.
Like any astronomical target, Alcor 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.
Alcor scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 points would lift it into a rarer tier.
That score comes from 6 science badges — Star, Naked-eye visible, Has a proper name, Never sets (northern circumpolar), White A-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.