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Epic exoplanet 51 EP

K2-39 b

RA 338.3682° · Dec -9.0229° · exoplanet

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Score breakdown

· 6 badges
51 pts · Epic
Epic 68 pts → Anomaly
  • Lava world +14
  • Hot Jupiter +10
  • Distant (>1000 ly) +10
  • Blasted by starlight +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 51

17 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Blasted by starlight · +8
  • Distant (>1000 ly) · +10

Trivia

What makes it special

  • Lava world. Its surface is likely an ocean of molten rock.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 17.6 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1.6 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 10 thousand years in a starship at a tenth of light speed.
  • Distance. 1003 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1023.

Saying hello

  • Say hello. A radio message and its reply would take 2006 years round-trip.

Standing on it

  • A year here. A full year lasts just 4.6 Earth days.

By the numbers

  • Size. About 6.3× the width of Earth.
  • Volume. About 247 Earths could fit inside it.
  • Mass. About 28.6× the mass of Earth.
  • Your weight. You'd weigh about 0.7× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. Around 1397°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by K2 using the transit method.

Properties

density gcc
0.93
discovery facility
K2
discovery method
Transit
dist ly
1002.8319
eccentricity
0
eq temp k
1670
insolation
1356
mass earth
28.6047
name
K2-39 b
orbital period days
4.6054
radius earth
6.277
sys num planets
1

About K2-39 b

K2-39 b is an epic exoplanet. It lies about 1,002.8 light-years from Earth, has an equilibrium temperature near 1,670 K, spans roughly 6.28 Earth radii and weighs about 28.6 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, K2-39 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 K2-39 b is an epic exoplanet

K2-39 b scores 51 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 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Blasted by starlight 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.