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Common star 20 EP

HD 12342

RA 30.6938° · Dec 57.3103° · star

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Score breakdown

· 4 badges
20 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Star +3
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B7IV — 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 subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

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 8.7 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Perseus.
  • 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 October — 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. ≈ 17.7 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.256
bv
0.052
constellation
Per
dist ly
1009.7708
luminosity
27.3905
mag
8.71
name
HD 12342
spect
B7IV

About HD 12342

HD 12342 is a common star. It lies about 1,009.8 light-years from Earth, sits in the constellation Per, shines at apparent magnitude 8.71 and has spectral type B7IV.

Its spectrum reads B7IV — 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 12342 in the constellation Per. At apparent magnitude 8.71, it is an easy target for binoculars.

Like any astronomical target, HD 12342 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 12342 is a common star

HD 12342 scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 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 Subgiant (leaving the main sequence) — 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.