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Rare star 47 EP

HD 34656

RA 80.1795° · Dec 37.4387° · 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

What it actually is

  • Spectral class. Its spectrum reads O7I... — 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.
  • Where it is in life. It is a supergiant. Drop it where the Sun is and its surface would engulf the inner planets.

Find it in the sky

  • How to spot it. At magnitude 6.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Auriga.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around December — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out brilliant white (B−V 0) — hotter and whiter than the Sun, the colour of Sirius or Vega.
  • 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 10130 K, against the Sun's 5778 K.

Properties

absmag
-13.21
bv
0
constellation
Aur
luminosity
16749428.7603
mag
6.79
name
HD 34656
spect
O7I...

About HD 34656

HD 34656 is a rare star. It sits in the constellation Aur, shines at apparent magnitude 6.79 and has spectral type O7I....

Its spectrum reads O7I... — 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 34656 in the constellation Aur. At apparent magnitude 6.79, it is an easy target for binoculars.

Like any astronomical target, HD 34656 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 34656 is a rare star

HD 34656 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.