Rare exoplanet 44 EP

Kepler-221 b

RA 296.6547° · Dec 46.8352° · exoplanet

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Score breakdown

· 6 badges

44 pts · Rare

Rare 46 pts → Epic

Puffy low-density world +12
Distant (>1000 ly) +10
Super-Earth +8
Multi-planet system +6
Confirmed exoplanet +5
Found by Kepler +3

Total score 44

2 more points to reach Epic.

Badges

Confirmed exoplanet · +5
Super-Earth · +8
Puffy low-density world · +12
Multi-planet system · +6
Found by Kepler · +3
Distant (>1000 ly) · +10

Trivia

What makes it special

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. ≈ 22.1 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 2 million years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 12.6 thousand years in a starship at a tenth of light speed.
Distance. 1256 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 770.

Saying hello

Say hello. A radio message and its reply would take 2513 years round-trip.

Standing on it

A year here. A full year lasts just 2.8 Earth days.

By the numbers

Size. About 1.7× the width of Earth.
Volume. About 5 Earths could fit inside it.
Mass. About 6× the mass of Earth.
Your weight. You'd weigh about 2.0× your Earth weight standing here.
Density. Less dense than water — drop it in a big enough ocean and it would float.
Temperature. Around 817°C — hotter than a self-cleaning oven.

How we found it

Discovery. Found by Kepler using the transit method.

Cosmic context

Crowded system. One of at least 4 planets orbiting its star.

Properties

density gcc: 0.19
discovery facility: Kepler
discovery method: Transit
dist ly: 1256.454
eccentricity: 0
eq temp k: 1090
insolation: 308.885
mass earth: 5.9558
name: Kepler-221 b
orbital period days: 2.7959
radius earth: 1.71
sys num planets: 4

About Kepler-221 b

Kepler-221 b is a rare exoplanet. It lies about 1,256.5 light-years from Earth, has an equilibrium temperature near 1,090 K, spans roughly 1.71 Earth radii and weighs about 5.96 Earth masses.

So low-density it would float on water.

How to see it

Like any astronomical target, Kepler-221 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-221 b is a rare exoplanet

Kepler-221 b scores 44 points on Spacedle's rarity scale, which places it in the rare tier. Another 2 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Super-Earth, Puffy low-density world, Multi-planet system, 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.