← Back to dex
Rare exoplanet 36 EP

Kepler-81 d

RA 293.6369° · Dec 42.8248° · exoplanet

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 5 badges
36 pts · Rare
Rare 50 pts → Epic
  • Earth-sized +16
  • Distant (over 1,000 light-years) +6
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Found by Kepler +3
Total score 36

14 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Distant (over 1,000 light-years) · +6
  • Earth-sized · +16
  • Multi-planet system · +6
  • Found by Kepler · +3

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

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. Denser than Earth — a solid world of rock and iron, with no meaningful atmosphere to speak of by mass.
  • Crowded system. One of at least 3 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 15.3 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Properties

density gcc
5.96
diameter km
15435.002
discovery facility
Kepler
discovery method
Transit
discovery year
2014
dist ly
1135.972
eccentricity
0
eq temp k
418
host star teff
4500
inclination
89.18
insolation
7.507
mag
15.258
mass earth
1.92
name
Kepler-81 d
orbital period days
20.8378
radius earth
1.21
semi major au
0.128
spect
M0 V
sys num planets
3
sys num stars
1

About Kepler-81 d

Kepler-81 d is a rare exoplanet. It lies about 1,136 light-years from Earth, shines at apparent magnitude 15.26, has spectral type M0 V and has an equilibrium temperature near 418 K.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 15.26, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Kepler-81 d 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 Kepler-81 d is a rare exoplanet

Kepler-81 d scores 36 points on Spacedle's rarity scale, which places it in the rare tier. Another 14 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Distant (over 1,000 light-years), Earth-sized, Multi-planet system and Found by Kepler — 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.