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Rare exoplanet 43 EP

K2-288 B b

RA 55.4443° · Dec 18.2685° · exoplanet

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Score breakdown

· 3 badges
43 pts · Rare
Rare 46 pts → Epic
  • In the habitable zone +30
  • Super-Earth +8
  • Confirmed exoplanet +5
Total score 43

3 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • In the habitable zone · +30
  • Super-Earth · +8

Trivia

What makes it special

  • Goldilocks zone. Sits where it's neither too hot nor too cold — liquid water could exist.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 3.8 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 334.1 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 2140 years in a starship at a tenth of light speed.
  • Distance. 214 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1812.

Saying hello

  • Say hello. A radio message and its reply would take 428 years round-trip.

Standing on it

  • A year here. A full year lasts just 31.4 Earth days.

By the numbers

  • Size. About 1.9× the width of Earth.
  • Volume. About 6.9 Earths could fit inside it.
  • Mass. About 4.3× the mass of Earth.
  • Your weight. You'd weigh about 1.2× your Earth weight standing here.
  • Temperature. A frigid -47°C — colder than dry ice.

How we found it

  • Discovery. Found by K2 using the transit method.

Properties

density gcc
3.42
discovery facility
K2
discovery method
Transit
dist ly
214.0033
eq temp k
226.36
habitable zone
yes
insolation
0.4368
mass earth
4.27
name
K2-288 B b
orbital period days
31.3935
radius earth
1.9
sys num planets
1

About K2-288 B b

K2-288 B b is a rare exoplanet. It lies about 214 light-years from Earth, has an equilibrium temperature near 226 K, spans roughly 1.9 Earth radii and weighs about 4.27 Earth masses.

Sits where it's neither too hot nor too cold — liquid water could exist.

How to see it

Like any astronomical target, K2-288 B 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 K2-288 B b is a rare exoplanet

K2-288 B b scores 43 points on Spacedle's rarity scale, which places it in the rare tier. Another 3 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, In the habitable zone and Super-Earth — 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.