Common star 17 EP

HD 43703

RA 94.6643° · Dec 23.0079° · star

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Score breakdown

· 4 badges

17 pts · Common

Common 22 pts → Uncommon

Hot blue B-type star +6
Subgiant (leaving the main sequence) +5
Star +3
On the zodiac +3

Total score 17

5 more points to reach Uncommon.

Badges

Star · +3
On the zodiac · +3
Hot blue B-type star · +6
Subgiant (leaving the main sequence) · +5

Trivia

Hard to believe

True brightness. It pours out about 3 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 B1IV:p... — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
Where it is in life. It is a subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

Find it in the sky

How to spot it. At magnitude 8.6 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-white (B−V 0.4) — a shade brighter and crisper than our own Sun.
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: -11.38
bv: 0.422
constellation: Gem
luminosity: 3104559.5881
mag: 8.62
name: HD 43703
spect: B1IV:p...

Nearby objects

About HD 43703

HD 43703 is a common star. It sits in the constellation Gem, shines at apparent magnitude 8.62 and has spectral type B1IV:p....

Its spectrum reads B1IV:p... — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for HD 43703 in the constellation Gem. At apparent magnitude 8.62, it is an easy target for binoculars.

Like any astronomical target, HD 43703 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 43703 is a common star

HD 43703 scores 17 points on Spacedle's rarity scale, which places it in the common tier. Another 5 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, Hot blue B-type star and Subgiant (leaving the main sequence) — 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.