← Back to dex
Uncommon exoplanet 28 EP

Kepler-87 b

RA 297.9168° · Dec 46.9651° · exoplanet

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

Computing the sky for your location…

Score breakdown

· 5 badges
28 pts · Uncommon
Uncommon 33 pts → Rare
  • Distant (>1000 ly) +10
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
  • Found by Kepler +3
Total score 28

5 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Multi-planet system · +6
  • Found by Kepler · +3
  • Distant (>1000 ly) · +10

Trivia

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 70.7 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 6.3 million years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 40.2 thousand years in a starship at a tenth of light speed.
  • Distance. 4021 light-years from Earth.

Look-back time

  • Look-back time. Its light left before the last ice age ended.

Saying hello

  • Say hello. A radio message and its reply would take 8042 years round-trip.

Standing on it

  • A year here. A full year lasts just 115 Earth days.

By the numbers

  • Size. About 13.5× the width of Earth.
  • Volume. About 2455 Earths could fit inside it.
  • Mass. Roughly 324× Earth's mass — about 1 Jupiters.
  • Your weight. You'd weigh about 1.8× your Earth weight standing here.
  • Density. Less dense than water — drop it in a big enough ocean and it would float.
  • Temperature. A scorching 205°C on average.

How we found it

  • Discovery. Found by Kepler using the transit method.

Cosmic context

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

Properties

density gcc
0.729
discovery facility
Kepler
discovery method
Transit
dist ly
4021.1773
eccentricity
0.036
eq temp k
478
insolation
9.203
mass earth
324.2
name
Kepler-87 b
orbital period days
114.7364
radius earth
13.49
sys num planets
2

About Kepler-87 b

Kepler-87 b is an uncommon exoplanet. It lies about 4,021.2 light-years from Earth, has an equilibrium temperature near 478 K, spans roughly 13.49 Earth radii and weighs about 324.2 Earth masses.

One of at least 2 planets orbiting its star.

How to see it

Like any astronomical target, Kepler-87 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 Kepler-87 b is an uncommon exoplanet

Kepler-87 b scores 28 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Multi-planet system, Found by Kepler and Distant (>1000 ly) — 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.

spacedle A daily roll through the real universe. © 2026 spacedle. Buy me a coffee

Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.