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Common star 20 EP

HR 55

RA 4.0579° · Dec 76.9508° · star

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Score breakdown

· 5 badges
20 pts · Common
Common 22 pts → Uncommon
  • Hot blue B-type star +6
  • Blue-white star +5
  • Never sets (northern circumpolar) +4
  • Star +3
  • Main-sequence star +2
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Never sets (northern circumpolar) · +4
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9Vn — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

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 6.3 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. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 11 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.07
bv
-0.044
constellation
Cep
dist ly
627.2231
luminosity
92.8966
mag
6.35
name
HR 55
spect
B9Vn

About HR 55

HR 55 is a common star. It lies about 627.2 light-years from Earth, sits in the constellation Cep, shines at apparent magnitude 6.35 and has spectral type B9Vn.

Its spectrum reads B9Vn — 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 HR 55 in the constellation Cep. At apparent magnitude 6.35, it is an easy target for binoculars.

Like any astronomical target, HR 55 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 HR 55 is a common star

HR 55 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 5 science badges — Star, Never sets (northern circumpolar), Hot blue B-type star, Main-sequence 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.