Rare star 43 EP

HD 53662

RA 106.5709° · Dec 10.2671° · star

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Score breakdown

· 5 badges

43 pts · Rare

Rare 50 pts → Epic

Blazing O-type star +26
Giant star +6
Blue-white star +5
Star +3
On the zodiac +3

Total score 43

7 more points to reach Epic.

Badges

Star · +3
On the zodiac · +3
Blazing O-type star · +26
Giant star · +6
Blue-white star · +5

Trivia

Hard to believe

True brightness. It pours out about 2.9 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 O7III — 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 giant. It has already exhausted its core hydrogen and swollen up enormously in response.

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 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 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.

Properties

absmag: -11.31
bv: -0.064
constellation: Gem
luminosity: 2910717.1181
mag: 8.69
name: HD 53662
spect: O7III

Nearby objects

About HD 53662

HD 53662 is a rare star. It sits in the constellation Gem, shines at apparent magnitude 8.69 and has spectral type O7III.

Its spectrum reads O7III — 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 53662 in the constellation Gem. At apparent magnitude 8.69, it is an easy target for binoculars.

Like any astronomical target, HD 53662 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 53662 is a rare star

HD 53662 scores 43 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, On the zodiac, Blazing O-type star, Giant 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.