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Epic exoplanet 58 EP

Kepler-12 b

RA 286.2434° · Dec 50.0404° · exoplanet

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Score breakdown

· 7 badges
58 pts · Epic
Epic 68 pts → Anomaly
  • Lava world +14
  • Puffy low-density world +12
  • Hot Jupiter +10
  • Distant (>1000 ly) +10
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 58

10 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Puffy low-density world · +12
  • Found by Kepler · +3
  • Distant (>1000 ly) · +10

Trivia

What makes it special

  • Lava world. Its surface is likely an ocean of molten rock.
  • Cotton-candy planet. So low-density it would float on water.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 50.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 4.5 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 28.7 thousand years in a starship at a tenth of light speed.
  • Distance. 2875 light-years from Earth.

Look-back time

  • Look-back time. Its light left before the last ice age ended.

Saying hello

  • Say hello. A radio message and its reply would take 5749 years round-trip.

Standing on it

  • A year here. A full year lasts just 4.4 Earth days.

By the numbers

  • Size. About 19.7× the width of Earth.
  • Volume. About 7600 Earths could fit inside it.
  • Mass. Roughly 137× Earth's mass — about 0.4 Jupiters.
  • Your weight. You'd weigh about 0.4× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 1207°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Kepler using the transit method.

Properties

density gcc
0.11
discovery facility
Kepler
discovery method
Transit
dist ly
2874.6933
eccentricity
0
eq temp k
1480
insolation
877.539
mass earth
137.3026
name
Kepler-12 b
orbital period days
4.438
radius earth
19.6606
sys num planets
1

About Kepler-12 b

Kepler-12 b is an epic exoplanet. It lies about 2,874.7 light-years from Earth, has an equilibrium temperature near 1,480 K, spans roughly 19.66 Earth radii and weighs about 137.3 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, Kepler-12 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-12 b is an epic exoplanet

Kepler-12 b scores 58 points on Spacedle's rarity scale, which places it in the epic tier. Another 10 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Puffy low-density world, Found by Kepler and Distant (>1000 ly) — 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.

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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.