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Rare star 47 EP

HD 167330

RA 273.8053° · Dec -12.5367° · star

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Score breakdown

· 3 badges
47 pts · Rare
Rare 50 pts → Epic
  • Blazing O-type star +26
  • Supergiant +18
  • Star +3
Total score 47

3 more points to reach Epic.

Badges

  • Star · +3
  • Blazing O-type star · +26
  • Supergiant · +18

Trivia

Hard to believe

  • True brightness. It pours out about 4.4 million times as much light as the Sun. It only looks ordinary because it is so far away.

What it actually is

  • Spectral class. Its spectrum reads O9.5/B0Ia.. — 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.

Find it in the sky

  • How to spot it. At magnitude 8.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Serpens.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around June — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out yellow (B−V 0.6) — almost exactly the Sun's own shade — a stellar twin in colour, if not in size.
  • Why no green stars. No star ever looks green: a surface hot enough to peak in green also floods out plenty of red and blue, and your eye blends the mixture back to white.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 5800 K, against the Sun's 5778 K.

Properties

absmag
-11.78
bv
0.643
constellation
Ser
luminosity
4487453.8993
mag
8.22
name
HD 167330
spect
O9.5/B0Ia..

Nearby objects

About HD 167330

HD 167330 is a rare star. It sits in the constellation Ser, shines at apparent magnitude 8.22 and has spectral type O9.5/B0Ia...

Its spectrum reads O9.5/B0Ia.. — 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.

How to see it

Look for HD 167330 in the constellation Ser. At apparent magnitude 8.22, it is an easy target for binoculars.

Like any astronomical target, HD 167330 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.

Why HD 167330 is a rare star

HD 167330 scores 47 points on Spacedle's rarity scale, which places it in the rare tier. Another 3 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, Blazing O-type star and Supergiant — 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.