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Uncommon star 22 EP

2 Per

RA 28.0390° · Dec 50.7928° · star

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Score breakdown

· 4 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
Total score 22

12 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9p... — 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 5.7 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.

Getting there

  • Aboard Voyager 1. ≈ 8.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 753.3 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.15
bv
-0.067
constellation
Per
dist ly
482.4793
luminosity
100
mag
5.7
name
2 Per
spect
B9p...

About 2 Per

2 Per is an uncommon star. It lies about 482.5 light-years from Earth, sits in the constellation Per, shines at apparent magnitude 5.7 and has spectral type B9p....

Its spectrum reads B9p... — 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 2 Per in the constellation Per. At apparent magnitude 5.7, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 2 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 2 Per is an uncommon star

2 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 4 science badges — Star, Naked-eye visible, 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.