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Uncommon exoplanet 33 EP

Kepler-1129 c

RA 291.6045° · Dec 41.3093° · exoplanet

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Score breakdown

· 6 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by Kepler +3
Total score 33

1 more point to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Found by Kepler · +3
  • Orbits a Sun-like star · +8

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.
  • 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 15.7 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 July — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

density gcc
2.13
diameter km
34824.426
discovery facility
Kepler
discovery method
Transit
discovery year
2016
dist ly
3861.2957
eccentricity
0
eq temp k
503
host star teff
5831
inclination
89.82
insolation
7.006
mag
15.661
mass earth
7.9
name
Kepler-1129 c
orbital period days
76.537
radius earth
2.73
semi major au
0.3537
sys num planets
2
sys num stars
1

About Kepler-1129 c

Kepler-1129 c is an uncommon exoplanet. It lies about 3,861.3 light-years from Earth, shines at apparent magnitude 15.66, has an equilibrium temperature near 503 K and spans roughly 2.73 Earth radii.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 15.66, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-1129 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 Kepler-1129 c is an uncommon exoplanet

Kepler-1129 c scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Sub-Neptune, Multi-planet system, Found by Kepler and Orbits a Sun-like 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.