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Uncommon star 24 EP

HD 239738

RA 325.4939° · Dec 58.5001° · star

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Score breakdown

· 5 badges
24 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Blue-white star +5
  • Never sets (northern circumpolar) +4
  • Star +3
Total score 24

10 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Never sets (northern circumpolar) · +4
  • Hot blue B-type star · +6
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B3 — 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 8.8 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cepheus.
  • 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 August — 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. ≈ 35.8 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 3.2 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.179
bv
-0.3
constellation
Cep
dist ly
2038.475
luminosity
102.707
mag
8.8
name
HD 239738
spect
B3

About HD 239738

HD 239738 is an uncommon star. It lies about 2,038.5 light-years from Earth, sits in the constellation Cep, shines at apparent magnitude 8.8 and has spectral type B3.

Its spectrum reads B3 — 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 239738 in the constellation Cep. At apparent magnitude 8.8, it is an easy target for binoculars.

Like any astronomical target, HD 239738 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 239738 is an uncommon star

HD 239738 scores 24 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 10 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Distant (over 1,000 light-years), Never sets (northern circumpolar), Hot blue B-type star and Blue-white 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.