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Common star 20 EP

20 Boo

RA 214.9385° · Dec 16.3069° · star

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Score breakdown

· 4 badges
20 pts · Common
Common 22 pts → Uncommon
  • Naked-eye visible +8
  • Giant star +6
  • Star +3
  • Orange K-type star +3
Total score 20

2 more points to reach Uncommon.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Orange K-type star · +3
  • Giant star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads K3III — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.
  • Where it is in life. It is a giant. It has already exhausted its core hydrogen and swollen up enormously in response.

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 4.8 you can see it with your own eyes from a dark site, over in Boötes.
  • 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 April — 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. ≈ 3.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.048
bv
1.228
constellation
Boo
dist ly
187.0159
luminosity
33.1742
mag
4.84
name
20 Boo
spect
K3III

About 20 Boo

20 Boo is a common star. It lies about 187 light-years from Earth, sits in the constellation Boo, shines at apparent magnitude 4.84 and has spectral type K3III.

Its spectrum reads K3III — a K-type star. Orange K dwarfs are the marathon runners of the galaxy, burning steadily for tens of billions of years.

How to see it

Look for 20 Boo in the constellation Boo. At apparent magnitude 4.84, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 20 Boo 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 20 Boo is a common star

20 Boo 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 4 science badges — Star, Naked-eye visible, Orange K-type star and Giant 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.