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Uncommon star 25 EP

81 Cet

RA 39.4242° · Dec -3.3962° · star

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Score breakdown

· 4 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Sun-like G-type star +8
  • Giant star +6
  • Star +3
Total score 25

9 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Sun-like G-type star · +8
  • Giant star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads G5III: — a G-type star: the very same spectral class as our own Sun.
  • 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 5.7 you can see it with your own eyes from a dark site, over in Cetus.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • 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. ≈ 5.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.819
bv
1.021
constellation
Cet
dist ly
301.7168
luminosity
40.9638
mag
5.65
name
81 Cet
spect
G5III:

About 81 Cet

81 Cet is an uncommon star. It lies about 301.7 light-years from Earth, sits in the constellation Cet, shines at apparent magnitude 5.65 and has spectral type G5III:.

Its spectrum reads G5III: — a G-type star: the very same spectral class as our own Sun.

How to see it

Look for 81 Cet in the constellation Cet. At apparent magnitude 5.65, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 81 Cet 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 81 Cet is an uncommon star

81 Cet scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Naked-eye visible, Sun-like G-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.