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Rare star 34 EP

HD 254755

RA 94.6324° · Dec 22.6792° · star

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Score breakdown

· 4 badges
34 pts · Rare
Rare 50 pts → Epic
  • Blazing O-type star +26
  • Star +3
  • On the zodiac +3
  • Main-sequence star +2
Total score 34

16 more points to reach Epic.

Badges

  • Star · +3
  • On the zodiac · +3
  • Blazing O-type star · +26
  • Main-sequence star · +2

Trivia

Hard to believe

  • True brightness. It pours out about 2.5 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 O9Vp — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

Find it in the sky

  • How to spot it. At magnitude 8.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Gemini.
  • 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 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.

Properties

absmag
-11.18
bv
0.591
constellation
Gem
luminosity
2582260.1906
mag
8.82
name
HD 254755
spect
O9Vp

About HD 254755

HD 254755 is a rare star. It sits in the constellation Gem, shines at apparent magnitude 8.82 and has spectral type O9Vp.

Its spectrum reads O9Vp — 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 254755 in the constellation Gem. At apparent magnitude 8.82, it is an easy target for binoculars.

Like any astronomical target, HD 254755 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 254755 is a rare star

HD 254755 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, Blazing O-type star and Main-sequence 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.