About K2-31 b
K2-31 b is an epic exoplanet. It lies about 360.5 light-years from Earth, has an equilibrium temperature near 1,688 K, spans roughly 11.88 Earth radii and weighs about 563.83 Earth masses.
Its surface is likely an ocean of molten rock.
Epic exoplanet 53 EP
K2-31 b
RA 245.4406° · Dec -23.5483° · exoplanet
Score breakdown
· 6 badgesEpic 68 pts → Anomaly
- Lava world +14
- Puffy low-density world +12
- Hot Jupiter +10
- Blasted by starlight +8
- Confirmed exoplanet +5
- Gas giant +4
Total score 53
15 more points to reach Anomaly.
Badges
- Confirmed exoplanet · +5
- Gas giant · +4
- Hot Jupiter · +10
- Lava world · +14
- Puffy low-density world · +12
- Blasted by starlight · +8
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. Hopelessly far for any craft humanity can build today.
Getting there
- Aboard Voyager 1. ≈ 6.3 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 562.9 thousand years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 3605 years in a starship at a tenth of light speed.
- Distance. 360 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 1666.
Saying hello
- Say hello. A radio message and its reply would take 721 years round-trip.
Standing on it
- A year here. A full year lasts just 1.3 Earth days.
By the numbers
- Size. About 11.9× the width of Earth.
- Volume. About 1677 Earths could fit inside it.
- Mass. Roughly 564× Earth's mass — about 1.8 Jupiters.
- Your weight. You'd weigh about 4.0× your Earth weight standing here.
- Density. Less dense than water — drop it in a big enough ocean and it would float.
- Temperature. Around 1415°C — hotter than a self-cleaning oven.
How we found it
- Discovery. Found by K2 using the transit method.
Properties
- density gcc
- 0.032
- discovery facility
- K2
- discovery method
- Transit
- dist ly
- 360.4904
- eccentricity
- 0
- eq temp k
- 1688
- insolation
- 1272
- mass earth
- 563.8304
- name
- K2-31 b
- orbital period days
- 1.2578
- radius earth
- 11.8815
- sys num planets
- 1
How to see it
Like any astronomical target, K2-31 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 K2-31 b is an epic exoplanet
K2-31 b scores 53 points on Spacedle's rarity scale, which places it in the epic tier. Another 15 points would lift it into a rarer tier.
That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Hot Jupiter, Lava world, Puffy low-density world and Blasted by starlight — 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.