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Epic exoplanet 61 EP

K2-188 b

RA 129.8137° · Dec 23.3574° · exoplanet

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Score breakdown

· 8 badges
61 pts · Epic
Epic 78 pts → Anomaly
  • Lava world +14
  • Tidally locked +10
  • Super-Earth +8
  • Orbits a Sun-like star +8
  • Distant (over 1,000 light-years) +6
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Blasted by starlight +4
Total score 61

17 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Super-Earth · +8
  • Lava world · +14
  • Tidally locked · +10
  • Multi-planet system · +6
  • Blasted by starlight · +4
  • Orbits a Sun-like star · +8

Trivia

What makes it special

  • Lava world. Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

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 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 12.7 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 January — that's when to go looking.

Properties

density gcc
5.34
diameter km
17220.87
discovery facility
K2
discovery method
Transit
discovery year
2018
dist ly
1457.3335
eq temp k
1692
host star teff
5977
inclination
83.9282
insolation
1945.6975
mag
12.657
mass earth
2.39
name
K2-188 b
orbital period days
1.7422
radius earth
1.35
semi major au
0.0289
sys num planets
2
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About K2-188 b

K2-188 b is an epic exoplanet. It lies about 1,457.3 light-years from Earth, shines at apparent magnitude 12.66, has an equilibrium temperature near 1,692 K and spans roughly 1.35 Earth radii.

Its surface is almost certainly an ocean of molten rock, kept liquid by the star it hugs.

How to see it

At apparent magnitude 12.66, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-188 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 K2-188 b is an epic exoplanet

K2-188 b scores 61 points on Spacedle's rarity scale, which places it in the epic tier. Another 17 points would lift it into a rarer tier.

That score comes from 8 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Super-Earth, Lava world, Tidally locked, Multi-planet system, Blasted by starlight 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.