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Common star 17 EP

HD 171357

RA 279.1712° · Dec -45.1192° · 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 B9Vn — 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 9.1 you'll want a small backyard telescope, over in Corona Australis.
  • 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 June — 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. ≈ 51.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.723
bv
0.004
constellation
CrA
dist ly
2938.3423
luminosity
169.5118
mag
9.05
name
HD 171357
spect
B9Vn

About HD 171357

HD 171357 is a common star. It lies about 2,938.3 light-years from Earth, sits in the constellation CrA, shines at apparent magnitude 9.05 and has spectral type B9Vn.

Its spectrum reads B9Vn — 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 171357 in the constellation CrA. At apparent magnitude 9.05, a small backyard telescope will bring it into view.

Like any astronomical target, HD 171357 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 171357 is a common star

HD 171357 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.