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Epic exoplanet 53 EP

TRAPPIST-1 c

RA 346.6264° · Dec -5.0435° · exoplanet

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Score breakdown

· 5 badges
53 pts · Epic
Epic 78 pts → Anomaly
  • Earth-sized +16
  • Richly packed system +14
  • Tidally locked +10
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
Total score 53

25 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Tidally locked · +10
  • Richly packed system · +14
  • Orbits a red dwarf · +8

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

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. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.
  • Crowded system. One of at least 7 planets orbiting its star.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 17 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • 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 September — that's when to go looking.

Properties

density gcc
5.464
diameter km
13993.5514
discovery facility
La Silla Observatory
discovery method
Transit
discovery year
2016
dist ly
40.5408
eccentricity
0.0065
eq temp k
339.7
host star teff
2566
inclination
89.778
insolation
2.214
mag
17.02
mass earth
1.308
name
TRAPPIST-1 c
orbital period days
2.4219
radius earth
1.097
semi major au
0.0158
spect
M8.0 V
sys num planets
7
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

Nearby objects

About TRAPPIST-1 c

TRAPPIST-1 c is an epic exoplanet. It lies about 40.5 light-years from Earth, shines at apparent magnitude 17.02, has spectral type M8.0 V and has an equilibrium temperature near 340 K.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 17.02, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, TRAPPIST-1 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 TRAPPIST-1 c is an epic exoplanet

TRAPPIST-1 c scores 53 points on Spacedle's rarity scale, which places it in the epic tier. Another 25 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Earth-sized, Tidally locked, Richly packed system and Orbits a red dwarf — 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.