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Common star 18 EP

HD 30123

RA 71.3945° · Dec 19.3283° · star

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Score breakdown

· 4 badges
18 pts · Common
Common 22 pts → Uncommon
  • Hot blue B-type star +6
  • Giant star +6
  • Star +3
  • On the zodiac +3
Total score 18

4 more points to reach Uncommon.

Badges

  • Star · +3
  • On the zodiac · +3
  • Hot blue B-type star · +6
  • Giant star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads B8III — 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 giant. It has already exhausted its core hydrogen and swollen up enormously in response.

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 8.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Taurus.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around December — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 13.2 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.577
bv
0.355
constellation
Tau
dist ly
751.5114
luminosity
20.3798
mag
8.39
name
HD 30123
spect
B8III

About HD 30123

HD 30123 is a common star. It lies about 751.5 light-years from Earth, sits in the constellation Tau, shines at apparent magnitude 8.39 and has spectral type B8III.

Its spectrum reads B8III — 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 30123 in the constellation Tau. At apparent magnitude 8.39, it is an easy target for binoculars.

Like any astronomical target, HD 30123 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 30123 is a common star

HD 30123 scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, 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.