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Uncommon exoplanet 30 EP

K2-138 e

RA 348.9490° · Dec -10.8497° · exoplanet

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Score breakdown

· 4 badges
30 pts · Uncommon
Uncommon 33 pts → Rare
  • Richly packed system +14
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 30

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Richly packed system · +14

Trivia

What makes it special

  • Packed system. Crammed into a system of five or more planets.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 11.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 6607 years in a starship at a tenth of light speed.
  • Distance. 661 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1365.

Saying hello

  • Say hello. A radio message and its reply would take 1321 years round-trip.

Standing on it

  • A year here. A full year lasts just 8.3 Earth days.

By the numbers

  • Size. About 3.4× the width of Earth.
  • Volume. About 39 Earths could fit inside it.
  • Mass. About 13× the mass of Earth.
  • Your weight. You'd weigh about 1.1× your Earth weight standing here.
  • Temperature. Around 484°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by K2 using the transit method.

Cosmic context

  • Crowded system. One of at least 6 planets orbiting its star.

Properties

density gcc
1.8
discovery facility
K2
discovery method
Transit
dist ly
660.7431
eccentricity
0.077
eq temp k
757
insolation
91.1
mass earth
12.97
name
K2-138 e
orbital period days
8.2615
radius earth
3.39
sys num planets
6
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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.