RA 214.0416° · Dec 51.3672° · star
3 more points to reach Rare.
21Iot Boo is an uncommon variable star. It lies about 94.8 light-years from Earth, sits in the constellation Boo, shines at apparent magnitude 4.75 and has spectral type A9V.
It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.
Look for 21Iot Boo in the constellation Boo. At apparent magnitude 4.75, it can be glimpsed with the unaided eye under dark skies.
Like any astronomical target, 21Iot Boo 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.
21Iot Boo scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.
That score comes from 7 science badges — Variable star, Naked-eye visible, Binary star, White A-type star, Main-sequence 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.