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Common star 17 EP

HD 128637

RA 220.1841° · Dec -63.5791° · 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 B4V — 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 10.1 you'll want a small backyard telescope, over in Centaurus.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • Best time of year. It stands highest in the middle of the night around May — 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. ≈ 32 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.354
bv
0.079
constellation
Cen
dist ly
1822.1005
luminosity
25.0265
mag
10.09
name
HD 128637
spect
B4V

About HD 128637

HD 128637 is a common star. It lies about 1,822.1 light-years from Earth, sits in the constellation Cen, shines at apparent magnitude 10.09 and has spectral type B4V.

Its spectrum reads B4V — 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 128637 in the constellation Cen. At apparent magnitude 10.09, a small backyard telescope will bring it into view.

Like any astronomical target, HD 128637 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 128637 is a common star

HD 128637 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.