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Common exoplanet 18 EP

KOI-984 c

RA 291.0489° · Dec 36.8401° · exoplanet

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Score breakdown

· 4 badges
18 pts · Common
Common 22 pts → Uncommon
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Found by Kepler · +3

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

  • 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. 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 12.8 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.

Properties

density gcc
0.411
diameter km
179862.42
discovery facility
Kepler
discovery method
Transit Timing Variations
discovery year
2022
dist ly
824.0886
eccentricity
0.38
eq temp k
597
host star teff
5295
insolation
22.0364
mag
12.795
mass earth
209.8
name
KOI-984 c
orbital period days
21.512
radius earth
14.1
semi major au
0.1467
sys num planets
2
sys num stars
1

About KOI-984 c

KOI-984 c is a common exoplanet. It lies about 824.1 light-years from Earth, shines at apparent magnitude 12.79, has an equilibrium temperature near 597 K and spans roughly 14.1 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 12.79, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, KOI-984 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 KOI-984 c is a common exoplanet

KOI-984 c scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Gas giant, Multi-planet system and Found by Kepler — 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.