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Rare exoplanet 35 EP

K2-151 b

RA 19.3048° · Dec 9.5013° · exoplanet

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Score breakdown

· 4 badges
35 pts · Rare
Rare 50 pts → Epic
  • Two suns in its sky +12
  • Tidally locked +10
  • Super-Earth +8
  • Confirmed exoplanet +5
Total score 35

15 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Super-Earth · +8
  • Tidally locked · +10
  • Two suns in its sky · +12

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 14.2 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. ≈ 4 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
4.7
diameter km
19006.738
discovery facility
K2
discovery method
Transit
discovery year
2018
dist ly
226.6125
eq temp k
566
host star teff
3695
insolation
20.8
mag
14.175
mass earth
2.83
multi star system
yes
name
K2-151 b
orbital period days
3.8355
radius earth
1.49
semi major au
0.0373
spect
M1.5 V
sys num planets
1
sys num stars
2
tidally locked
yes
tidally locked inferred
yes

About K2-151 b

K2-151 b is a rare exoplanet. It lies about 226.6 light-years from Earth, shines at apparent magnitude 14.18, has spectral type M1.5 V and has an equilibrium temperature near 566 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 14.18, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-151 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 K2-151 b is a rare exoplanet

K2-151 b scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Super-Earth, Tidally locked and Two suns in its sky — 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.