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Rare star 36 EP

HD 52533

RA 105.3627° · Dec -3.1176° · star

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Score breakdown

· 4 badges
36 pts · Rare
Rare 50 pts → Epic
  • Blazing O-type star +26
  • Blue-white star +5
  • Star +3
  • Main-sequence star +2
Total score 36

14 more points to reach Epic.

Badges

  • Star · +3
  • Blazing O-type star · +26
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. 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.
  • 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 7.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Monoceros.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around January — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out blue-white (B−V -0.1) — the hallmark of a surface far hotter than the Sun's.
  • 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 11360 K, against the Sun's 5778 K.

Properties

absmag
-12.3
bv
-0.087
constellation
Mon
luminosity
7244359.6007
mag
7.7
name
HD 52533
spect
O9V

About HD 52533

HD 52533 is a rare star. It sits in the constellation Mon, shines at apparent magnitude 7.7 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.

How to see it

Look for HD 52533 in the constellation Mon. At apparent magnitude 7.7, it is an easy target for binoculars.

Like any astronomical target, HD 52533 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 52533 is a rare star

HD 52533 scores 36 points on Spacedle's rarity scale, which places it in the rare tier. Another 14 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Blazing O-type star, Main-sequence star and Blue-white 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.