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Epic exoplanet 54 EP

Kepler-17 b

RA 298.3952° · Dec 47.8150° · exoplanet

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Score breakdown

· 7 badges
54 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
  • Found by Kepler +3
Total score 54

14 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Hot Jupiter · +10
  • Lava world · +14
  • Blasted by starlight · +8
  • Found by Kepler · +3
  • 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. ≈ 41.3 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 3.7 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 23.5 thousand years in a starship at a tenth of light speed.
  • Distance. 2351 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 4702 years round-trip.

Standing on it

  • A year here. A full year lasts just 1.5 Earth days.

By the numbers

  • Size. About 14.7× the width of Earth.
  • Volume. About 3164 Earths could fit inside it.
  • Mass. Roughly 779× Earth's mass — about 2.5 Jupiters.
  • Your weight. You'd weigh about 3.6× your Earth weight standing here.
  • Temperature. Around 1297°C — hotter than a self-cleaning oven.

How we found it

  • Discovery. Found by Kepler using the transit method.

Properties

density gcc
1.35
discovery facility
Kepler
discovery method
Transit
dist ly
2350.7792
eccentricity
0.011
eq temp k
1570
insolation
1481.766
mass earth
778.65
name
Kepler-17 b
orbital period days
1.4857
radius earth
14.68
sys num planets
1

About Kepler-17 b

Kepler-17 b is an epic exoplanet. It lies about 2,350.8 light-years from Earth, has an equilibrium temperature near 1,570 K, spans roughly 14.68 Earth radii and weighs about 778.65 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, Kepler-17 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-17 b is an epic exoplanet

Kepler-17 b scores 54 points on Spacedle's rarity scale, which places it in the epic tier. Another 14 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Blasted by starlight, 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.

spacedle A daily roll through the real universe. © 2026 spacedle. Buy me a coffee

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.