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Uncommon star 22 EP

13The Per

RA 41.0495° · Dec 49.2284° · star

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Score breakdown

· 5 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Binary star +6
  • Star +3
  • Yellow-white F-type star +3
  • Main-sequence star +2
Total score 22

12 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Binary star · +6
  • Yellow-white F-type star · +3
  • Main-sequence star · +2

Trivia

What makes it special

  • Not one star but two. It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

What it actually is

  • Spectral class. Its spectrum reads F7V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • 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. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 4.1 you can see it with your own eyes from a dark site, over in Perseus.
  • 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 October — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Properties

absmag
3.868
binary
yes
bv
0.514
constellation
Per
dist ly
36.292
luminosity
2.4706
mag
4.1
name
13The Per
spect
F7V

About 13The Per

13The Per is an uncommon star. It lies about 36.3 light-years from Earth, sits in the constellation Per, shines at apparent magnitude 4.1 and has spectral type F7V.

It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

How to see it

Look for 13The Per in the constellation Per. At apparent magnitude 4.1, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 13The Per 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 13The Per is an uncommon star

13The Per scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Naked-eye visible, Binary star, Yellow-white F-type star and Main-sequence 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.