RA 289.2645° · Dec 9.3441° · star
9 more points to reach Rare.
HD 180639 is an uncommon variable star. It lies about 218 light-years from Earth, sits in the constellation Aql, shines at apparent magnitude 8.73 and has spectral type A4II.
Its spectrum reads A4II — 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 HD 180639 in the constellation Aql. At apparent magnitude 8.73, it is an easy target for binoculars.
Like any astronomical target, HD 180639 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 180639 scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.
That score comes from 4 science badges — Variable star, White A-type star, Bright giant 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.