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Trash exoplanet 14 EP

Kepler-138 b

RA 290.3814° · Dec 43.2931° · exoplanet

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Score breakdown

· 3 badges
14 pts · Trash
Trash 15 pts → Common
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Found by Kepler +3
Total score 14

1 more point to reach Common.

Badges

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

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 4 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 13 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. Hopelessly far for any craft humanity can build today.

Properties

density gcc
1.7
diameter km
8163.968
discovery facility
Kepler
discovery method
Transit
discovery year
2014
dist ly
218.0757
eccentricity
0.02
eq temp k
452
host star teff
3841
inclination
88.67
insolation
9.9
mag
13.04
mass earth
0.07
name
Kepler-138 b
orbital period days
10.3134
radius earth
0.64
semi major au
0.0753
spect
M1 V
sys num planets
4
sys num stars
1

About Kepler-138 b

Kepler-138 b is a trash exoplanet. It lies about 218.1 light-years from Earth, shines at apparent magnitude 13.04, has spectral type M1 V and has an equilibrium temperature near 452 K.

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 13.04, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-138 b 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-138 b is a trash exoplanet

Kepler-138 b scores 14 points on Spacedle's rarity scale, which places it in the trash tier. Another 1 point would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, 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.