RA 199.5605° · Dec 49.6821° · star
4 more points to reach Rare.
21 CVn is an uncommon variable star. It lies about 274.8 light-years from Earth, sits in the constellation CVn, shines at apparent magnitude 5.14 and has spectral type A0V.
Its spectrum reads A0V — 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 21 CVn in the constellation CVn. At apparent magnitude 5.14, it can be glimpsed with the unaided eye under dark skies.
Like any astronomical target, 21 CVn 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.
21 CVn 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 7 science badges — Variable star, Naked-eye visible, White A-type star, Main-sequence star, Blue-white star, Barely variable (under 0.05 mag) and A named variable 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.