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Trash exoplanet 9 EP

GJ 436 b

RA 175.5505° · Dec 26.7031° · exoplanet

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Score breakdown

· 2 badges
9 pts · Trash
Trash 15 pts → Common
  • Confirmed exoplanet +5
  • Neptune-like +4
Total score 9

6 more points to reach Common.

Badges

  • Confirmed exoplanet · +5
  • Neptune-like · +4

Trivia

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 559 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 49.7 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 318 years in a starship at a tenth of light speed.
  • Distance. 31.8 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1994.

Saying hello

  • Say hello. A radio message and its reply would take 63.6 years round-trip.

Standing on it

  • A year here. A full year lasts just 2.6 Earth days.

By the numbers

  • Size. About 4.2× the width of Earth.
  • Volume. About 72.5 Earths could fit inside it.
  • Mass. About 22.1× the mass of Earth.
  • Your weight. You'd weigh about 1.3× your Earth weight standing here.
  • Temperature. A scorching 413°C on average.

How we found it

  • Discovery. Found by W. M. Keck Observatory using the radial velocity method.

Properties

density gcc
1.8
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
dist ly
31.8107
eccentricity
0.1383
eq temp k
686
insolation
29.4322
mass earth
22.1
name
GJ 436 b
orbital period days
2.6439
radius earth
4.17
sys num planets
1

About GJ 436 b

GJ 436 b is a trash exoplanet. It lies about 31.8 light-years from Earth, has an equilibrium temperature near 686 K, spans roughly 4.17 Earth radii and weighs about 22.1 Earth masses.

About 4.2× the width of Earth.

How to see it

Like any astronomical target, GJ 436 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 GJ 436 b is a trash exoplanet

GJ 436 b scores 9 points on Spacedle's rarity scale, which places it in the trash tier. Another 6 points would lift it into a rarer tier.

That score comes from 2 science badges — Confirmed exoplanet and Neptune-like — 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.