RA 279.0325° · Dec 9.1910° · star
6 more points to reach Common.
HD 171729 is a trash star. It sits in the constellation Oph, shines at apparent magnitude 9.9 and has spectral type B9.
Its spectrum reads B9 — 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 171729 in the constellation Oph. At apparent magnitude 9.9, a small backyard telescope will bring it into view.
Like any astronomical target, HD 171729 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 171729 scores 9 points on Spacedle's rarity scale, which places it in the trash tier. Another 6 points would lift it into a rarer tier.
That score comes from 2 science badges — Star and Hot blue B-type 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.