RA 302.4150° · Dec 21.0788° · star
5 more points to reach Rare.
HD 191531 is an uncommon variable star. It sits in the constellation Sge, shines at apparent magnitude 8.35 and has spectral type B0.5III-IV.
Its spectrum reads B0.5III-IV — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
Look for HD 191531 in the constellation Sge. At apparent magnitude 8.35, it is an easy target for binoculars.
Like any astronomical target, HD 191531 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 191531 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.
That score comes from 6 science badges — Variable star, Hot blue B-type star, Giant star, Blue-white star, Gently variable 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.