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Common star 21 EP

HD 128239

RA 219.1606° · Dec -31.0363° · star

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Score breakdown

· 4 badges
21 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Giant star +6
  • Star +3
Total score 21

1 more point to reach Uncommon.

Badges

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

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9.5/A0III/ — 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.

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 8.6 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Centaurus.
  • 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 April — 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. ≈ 21.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.9 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
0.763
bv
0.021
constellation
Cen
dist ly
1199.1031
luminosity
43.132
mag
8.59
name
HD 128239
spect
B9.5/A0III/

About HD 128239

HD 128239 is a common star. It lies about 1,199.1 light-years from Earth, sits in the constellation Cen, shines at apparent magnitude 8.59 and has spectral type B9.5/A0III/.

Its spectrum reads B9.5/A0III/ — 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 128239 in the constellation Cen. At apparent magnitude 8.59, it is an easy target for binoculars.

Like any astronomical target, HD 128239 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 128239 is a common star

HD 128239 scores 21 points on Spacedle's rarity scale, which places it in the common tier. Another 1 point 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 Giant 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.