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Common star 19 EP

HD 237021

RA 43.3763° · Dec 58.6123° · 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 B9 — 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 9.5 you'll want a small backyard telescope, over in Cassiopeia.
  • 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 November — 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. ≈ 54.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 4.9 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.364
bv
0.286
constellation
Cas
dist ly
3106.2478
luminosity
121.7867
mag
9.53
name
HD 237021
spect
B9

About HD 237021

HD 237021 is a common star. It lies about 3,106.2 light-years from Earth, sits in the constellation Cas, shines at apparent magnitude 9.53 and has spectral type B9.

Its spectrum reads B9 — 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 237021 in the constellation Cas. At apparent magnitude 9.53, a small backyard telescope will bring it into view.

Like any astronomical target, HD 237021 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 237021 is a common star

HD 237021 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.