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Common star 19 EP

HD 240121

RA 343.9597° · Dec 60.0096° · star

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Score breakdown

· 4 badges
19 pts · Common
Common 22 pts → Uncommon
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Never sets (northern circumpolar) +4
  • Star +3
Total score 19

3 more points to reach Uncommon.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Never sets (northern circumpolar) · +4
  • Hot blue B-type star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads B8 — 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 9.6 you'll want a small backyard telescope, 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. ≈ 21.5 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
1.724
bv
0.16
constellation
Cep
dist ly
1226.1502
luminosity
17.7992
mag
9.6
name
HD 240121
spect
B8

About HD 240121

HD 240121 is a common star. It lies about 1,226.2 light-years from Earth, sits in the constellation Cep, shines at apparent magnitude 9.6 and has spectral type B8.

Its spectrum reads B8 — 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 240121 in the constellation Cep. At apparent magnitude 9.6, a small backyard telescope will bring it into view.

Like any astronomical target, HD 240121 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 240121 is a common star

HD 240121 scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Distant (over 1,000 light-years), Never sets (northern circumpolar) and Hot blue B-type 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.