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Uncommon star 33 EP

HD 187311

RA 297.7696° · Dec -41.0232° · star

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Score breakdown

· 7 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Toward the galactic centre +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
  • On the zodiac +3
  • Main-sequence star +2
Total score 33

1 more point to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B3V — 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 10.2 you'll want a small backyard telescope, over in Sagittarius.
  • 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 July — 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. ≈ 18.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
2.683
bv
-0.146
constellation
Sgr
dist ly
1058.948
luminosity
7.3587
mag
10.24
name
HD 187311
spect
B3V

About HD 187311

HD 187311 is an uncommon star. It lies about 1,058.9 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 10.24 and has spectral type B3V.

Its spectrum reads B3V — 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 187311 in the constellation Sgr. At apparent magnitude 10.24, a small backyard telescope will bring it into view.

Like any astronomical target, HD 187311 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 187311 is an uncommon star

HD 187311 scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 7 science badges — Star, Distant (over 1,000 light-years), Toward the galactic centre, On the zodiac, Hot blue B-type star, Main-sequence 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.