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Uncommon star 27 EP

HD 123100

RA 212.0159° · Dec -64.5396° · star

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Score breakdown

· 4 badges
27 pts · Uncommon
Uncommon 34 pts → Rare
  • Bright giant +12
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Star +3
Total score 27

7 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Bright giant · +12

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9II — 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 bright giant, well on its way to the largest stars there are.

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 8.2 it is just past naked-eye reach — ordinary binoculars will pull it in, 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 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. ≈ 21.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.29
bv
0.13
constellation
Cen
dist ly
1240.1368
luminosity
66.6807
mag
8.19
name
HD 123100
spect
B9II

About HD 123100

HD 123100 is an uncommon star. It lies about 1,240.1 light-years from Earth, sits in the constellation Cen, shines at apparent magnitude 8.19 and has spectral type B9II.

Its spectrum reads B9II — 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 123100 in the constellation Cen. At apparent magnitude 8.19, it is an easy target for binoculars.

Like any astronomical target, HD 123100 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 123100 is an uncommon star

HD 123100 scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 7 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 Bright giant — 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.