About K2-66 b
K2-66 b is a rare exoplanet. It lies about 1,676 light-years from Earth, has an equilibrium temperature near 1,372 K, spans roughly 2.49 Earth radii and weighs about 21.3 Earth masses.
Its surface is likely an ocean of molten rock.
Rare exoplanet 34 EP
K2-66 b
RA 331.5267° · Dec -10.7115° · exoplanet
Score breakdown
· 4 badgesRare 46 pts → Epic
- Lava world +14
- Distant (>1000 ly) +10
- Confirmed exoplanet +5
- Sub-Neptune +5
Total score 34
12 more points to reach Epic.
Badges
- Confirmed exoplanet · +5
- Sub-Neptune · +5
- Lava world · +14
- 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. ≈ 29.5 million years at Voyager 1's speed (17 km/s).
- Fastest probe ever. ≈ 2.6 million years even at the Parker Solar Probe's 192 km/s.
- At 10% light speed. ≈ 16.8 thousand years in a starship at a tenth of light speed.
- Distance. 1676 light-years from Earth.
Look-back time
- Look-back time. The light you'd see left around the year 350.
Saying hello
- Say hello. A radio message and its reply would take 3352 years round-trip.
Standing on it
- A year here. A full year lasts just 5.1 Earth days.
By the numbers
- Size. About 2.5× the width of Earth.
- Volume. About 15.4 Earths could fit inside it.
- Mass. About 21.3× the mass of Earth.
- Your weight. You'd weigh about 3.4× your Earth weight standing here.
- Temperature. Around 1099°C — hotter than a self-cleaning oven.
How we found it
- Discovery. Found by K2 using the transit method.
Properties
- density gcc
- 7.8
- discovery facility
- K2
- discovery method
- Transit
- dist ly
- 1676.0407
- eccentricity
- 0
- eq temp k
- 1372
- insolation
- 840
- mass earth
- 21.3
- name
- K2-66 b
- orbital period days
- 5.0696
- radius earth
- 2.49
- sys num planets
- 1
How to see it
Like any astronomical target, K2-66 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 K2-66 b is a rare exoplanet
K2-66 b scores 34 points on Spacedle's rarity scale, which places it in the rare tier. Another 12 points would lift it into a rarer tier.
That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, Lava world 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.