Rare star 39 EP

HD 105627

RA 182.4358° · Dec -62.5818° · star

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Score breakdown

· 4 badges

39 pts · Rare

Rare 50 pts → Epic

Blazing O-type star +26
Under the Southern Cross +8
Star +3
Main-sequence star +2

Total score 39

11 more points to reach Epic.

Badges

Star · +3
Under the Southern Cross · +8
Blazing O-type star · +26
Main-sequence star · +2

Trivia

Hard to believe

True brightness. It pours out about 4.7 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 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 8.1 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Crux.
Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
Best time of year. It stands highest in the middle of the night around March — 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.

Properties

absmag: -11.86
bv: 0.042
constellation: Cru
luminosity: 4830588.0204
mag: 8.14
name: HD 105627
spect: O9V

Nearby objects

About HD 105627

HD 105627 is a rare star. It sits in the constellation Cru, shines at apparent magnitude 8.14 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 105627 in the constellation Cru. At apparent magnitude 8.14, it is an easy target for binoculars.

Like any astronomical target, HD 105627 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 105627 is a rare star

HD 105627 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Under the Southern Cross, 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.