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Rare exoplanet 39 EP

75 Cet c

RA 38.0392° · Dec -1.0350° · exoplanet

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Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Its star is visible to the naked eye +12
  • Two suns in its sky +12
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 39

11 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Its star is visible to the naked eye · +12
  • Two suns in its sky · +12

Trivia

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

What it actually is

  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.
  • Crowded system. One of at least 2 planets orbiting its star.

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 5.4 you can see it with your own eyes from a dark site.
  • 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.

Properties

density gcc
0.593
diameter km
177311.18
discovery facility
Okayama Astrophysical Observatory
discovery method
Radial Velocity
discovery year
2023
dist ly
270.5833
eccentricity
0.023
eq temp k
376.92
host star teff
4809
insolation
3.3569
mag
5.3532
mass earth
289.8595
multi star system
yes
name
75 Cet c
orbital period days
2051.62
radius earth
13.9
semi major au
3.929
spect
G3 III
sys num planets
2
sys num stars
2

About 75 Cet c

75 Cet c is a rare exoplanet. It lies about 270.6 light-years from Earth, shines at apparent magnitude 5.35, has spectral type G3 III and has an equilibrium temperature near 377 K.

Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

How to see it

At apparent magnitude 5.35, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 75 Cet c 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 75 Cet c is a rare exoplanet

75 Cet c scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Multi-planet system, Its star is visible to the naked eye and Two suns in its sky — 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.