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Uncommon exoplanet 31 EP

K2-208 b

RA 20.7790° · Dec 0.8890° · exoplanet

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Score breakdown

· 4 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Super-Earth +8
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
Total score 31

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Super-Earth · +8
  • Tidally locked · +10
  • Orbits a Sun-like star · +8

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 12.6 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around October — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 14.7 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
4.04
diameter km
21361.8096
discovery facility
K2
discovery method
Transit
discovery year
2018
dist ly
837.8524
eccentricity
0.37
eq temp k
1122
host star teff
5500
inclination
86.94
insolation
264.3425
mag
12.577
mass earth
3.45
name
K2-208 b
orbital period days
4.191
radius earth
1.6746
semi major au
0.0488
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About K2-208 b

K2-208 b is an uncommon exoplanet. It lies about 837.9 light-years from Earth, shines at apparent magnitude 12.58, has an equilibrium temperature near 1,122 K and spans roughly 1.67 Earth radii.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 12.58, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-208 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 K2-208 b is an uncommon exoplanet

K2-208 b scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Super-Earth, Tidally locked and Orbits a Sun-like star — 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.