Rare star 35 EP

HIP 118113

RA 359.3859° · Dec 67.5542° · star

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Score breakdown

· 4 badges

35 pts · Rare

Rare 50 pts → Epic

Blazing O-type star +26
Never sets (northern circumpolar) +4
Star +3
Main-sequence star +2

Total score 35

15 more points to reach Epic.

Badges

Star · +3
Never sets (northern circumpolar) · +4
Blazing O-type star · +26
Main-sequence star · +2

Trivia

Hard to believe

True brightness. It pours out about 2.8 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 8.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cepheus.
Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
Best time of year. It stands highest in the middle of the night around September — that's when to go looking.

Its true colour

Its true colour. Measured through blue and visual filters it comes out yellow (B−V 0.7) — 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: -11.28
bv: 0.681
constellation: Cep
luminosity: 2831391.9958
mag: 8.72
name: HIP 118113
spect: O9V

Nearby objects

About HIP 118113

HIP 118113 is a rare star. It sits in the constellation Cep, shines at apparent magnitude 8.72 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 HIP 118113 in the constellation Cep. At apparent magnitude 8.72, it is an easy target for binoculars.

Like any astronomical target, HIP 118113 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 HIP 118113 is a rare star

HIP 118113 scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Never sets (northern circumpolar), 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.