RA 169.1411° · Dec -62.1155° · star
10 more points to reach Epic.
HD 308399 is a rare variable star. It sits in the constellation Car, shines at apparent magnitude 11.07 and has spectral type O9V.
Its spectrum reads O9V — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.
Look for HD 308399 in the constellation Car. At apparent magnitude 11.07, a small backyard telescope will bring it into view.
Like any astronomical target, HD 308399 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 308399 scores 40 points on Spacedle's rarity scale, which places it in the rare tier. Another 10 points would lift it into a rarer tier.
That score comes from 5 science badges — Variable star, Blazing O-type star, Main-sequence 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.