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Common exoplanet 18 EP

K2-388 b

RA 352.7139° · Dec -11.0774° · exoplanet

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Score breakdown

· 3 badges
18 pts · Common
Common 22 pts → Uncommon
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • 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. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

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 12.9 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around September — 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. ≈ 16.6 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
1.34
diameter km
49749.18
discovery facility
K2
discovery method
Transit
discovery year
2022
dist ly
947.4669
eq temp k
874
host star teff
5310
insolation
138
mag
12.861
mass earth
14.5
name
K2-388 b
orbital period days
6.3393
radius earth
3.9
spect
G8
sys num planets
1
sys num stars
1

About K2-388 b

K2-388 b is a common exoplanet. It lies about 947.5 light-years from Earth, shines at apparent magnitude 12.86, has spectral type G8 and has an equilibrium temperature near 874 K.

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 12.86, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-388 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 K2-388 b is a common exoplanet

K2-388 b scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Sub-Neptune 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.