RA 279.8760° · Dec -21.9656° · star
2 more points to reach Rare.
HD 172158 is an uncommon star. It sits in the constellation Sgr, shines at apparent magnitude 7.9 and has spectral type B8II.
Its spectrum reads B8II — 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 172158 in the constellation Sgr. At apparent magnitude 7.9, it is an easy target for binoculars.
Like any astronomical target, HD 172158 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 172158 scores 32 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 2 points would lift it into a rarer tier.
That score comes from 5 science badges — Star, Toward the galactic centre, On the zodiac, Hot blue B-type star and Bright giant — 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.