← Back to dex
Common exoplanet 20 EP

K2-77 b

RA 55.2285° · Dec 12.5724° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 3 badges
20 pts · Common
Common 22 pts → Uncommon
  • Tidally locked +10
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 20

2 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Tidally locked · +10

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.

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 12.2 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 November — 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. ≈ 8.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 721.8 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

diameter km
31885.432
discovery facility
K2
discovery method
Transit
discovery year
2016
dist ly
462.2642
eccentricity
0.29
eq temp k
806
host star teff
5160
inclination
88.33
insolation
58
mag
12.224
mass earth
603.877
name
K2-77 b
orbital period days
8.2001
radius earth
2.4996
semi major au
0.0753
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About K2-77 b

K2-77 b is a common exoplanet. It lies about 462.3 light-years from Earth, shines at apparent magnitude 12.22, has an equilibrium temperature near 806 K and spans roughly 2.5 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 12.22, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, K2-77 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 K2-77 b is a common exoplanet

K2-77 b scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 points would lift it into a rarer tier.

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