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Rare star 34 EP

HD 218342

RA 346.5374° · Dec 63.2128° · star

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Score breakdown

· 6 badges
34 pts · Rare
Rare 50 pts → Epic
  • Intrinsically luminous (Mv < −2) +10
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Never sets (northern circumpolar) +4
  • Star +3
Total score 34

16 more points to reach Epic.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Never sets (northern circumpolar) · +4
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Intrinsically luminous (Mv < −2) · +10

Trivia

What it actually is

  • Spectral class. Its spectrum reads B0IV — 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 7.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cepheus.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around September — 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. ≈ 55.6 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-2.496
bv
0.342
constellation
Cep
dist ly
3166.5632
luminosity
867.7607
mag
7.44
name
HD 218342
spect
B0IV

About HD 218342

HD 218342 is a rare star. It lies about 3,166.6 light-years from Earth, sits in the constellation Cep, shines at apparent magnitude 7.44 and has spectral type B0IV.

Its spectrum reads B0IV — 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 218342 in the constellation Cep. At apparent magnitude 7.44, it is an easy target for binoculars.

Like any astronomical target, HD 218342 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 218342 is a rare star

HD 218342 scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 16 points would lift it into a rarer tier.

That score comes from 6 science badges — Star, Distant (over 1,000 light-years), Never sets (northern circumpolar), Hot blue B-type star, Subgiant (leaving the main sequence) and Intrinsically luminous (Mv < −2) — 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.