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Uncommon exoplanet 25 EP

K2-43 b

RA 169.1170° · Dec -3.9754° · exoplanet

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Score breakdown

· 4 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 25

9 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4
  • Tidally locked · +10
  • Multi-planet system · +6

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.
  • Crowded system. One of at least 2 planets orbiting its star.

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 15.7 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 March — that's when to go looking.

Could we get there?

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

Properties

density gcc
1.11
diameter km
57530.462
discovery facility
K2
discovery method
Transit
discovery year
2016
dist ly
595.3521
eccentricity
0.07
eq temp k
939.3
host star teff
3840.6
inclination
89.6
insolation
49
mag
15.748
mass earth
18.5
name
K2-43 b
orbital period days
3.4711
radius earth
4.51
semi major au
0.0378
sys num planets
2
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About K2-43 b

K2-43 b is an uncommon exoplanet. It lies about 595.4 light-years from Earth, shines at apparent magnitude 15.75, has an equilibrium temperature near 939 K and spans roughly 4.51 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 15.75, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-43 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 K2-43 b is an uncommon exoplanet

K2-43 b scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Neptune-like, Tidally locked and Multi-planet system — 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.