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Common star 17 EP

HD 203731

RA 320.7131° · Dec 40.6972° · star

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Score breakdown

· 4 badges
17 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Star +3
  • Main-sequence star +2
Total score 17

5 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads B1Vne — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 7.5 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cygnus.
  • 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 August — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 25.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.728
bv
0.045
constellation
Cyg
dist ly
1462.583
luminosity
170.2943
mag
7.53
name
HD 203731
spect
B1Vne

About HD 203731

HD 203731 is a common star. It lies about 1,462.6 light-years from Earth, sits in the constellation Cyg, shines at apparent magnitude 7.53 and has spectral type B1Vne.

Its spectrum reads B1Vne — 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 203731 in the constellation Cyg. At apparent magnitude 7.53, it is an easy target for binoculars.

Like any astronomical target, HD 203731 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 203731 is a common star

HD 203731 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, Distant (over 1,000 light-years), Hot blue B-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.