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Common star 20 EP

HD 205805

RA 324.7941° · Dec -46.0976° · star

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Score breakdown

· 4 badges
20 pts · Common
Common 22 pts → Uncommon
  • Hot blue B-type star +6
  • Giant star +6
  • Blue-white star +5
  • Star +3
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Hot blue B-type star · +6
  • Giant star · +6
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B7III — 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 giant. It has already exhausted its core hydrogen and swollen up enormously in response.

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 10.2 you'll want a small backyard telescope, over in Grus.
  • Southern sky. It rides the southern half of the sky — an easier target the further south 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. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 15.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
3.05
bv
-0.241
constellation
Gru
dist ly
869.7494
luminosity
5.2481
mag
10.18
name
HD 205805
spect
B7III

About HD 205805

HD 205805 is a common star. It lies about 869.7 light-years from Earth, sits in the constellation Gru, shines at apparent magnitude 10.18 and has spectral type B7III.

Its spectrum reads B7III — 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 205805 in the constellation Gru. At apparent magnitude 10.18, a small backyard telescope will bring it into view.

Like any astronomical target, HD 205805 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 205805 is a common star

HD 205805 scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Hot blue B-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.