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Uncommon exoplanet 33 EP

Gliese 12 b

RA 3.9579° · Dec 13.5576° · exoplanet

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Score breakdown

· 4 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Earth-sized +16
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 33

1 more point to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Found by TESS · +4
  • Orbits a red dwarf · +8

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.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 12.6 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 September — that's when to go looking.

Could we get there?

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

Properties

density gcc
6.4
diameter km
11863.266
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2024
dist ly
39.8236
eccentricity
0.24
eq temp k
314.6
host star teff
3328
inclination
89.25
insolation
1.62
mag
12.6
mass earth
0.95
name
Gliese 12 b
orbital period days
12.7614
radius earth
0.93
semi major au
0.067
spect
M4 V
sys num planets
1
sys num stars
1

About Gliese 12 b

Gliese 12 b is an uncommon exoplanet. It lies about 39.8 light-years from Earth, shines at apparent magnitude 12.6, has spectral type M4 V and has an equilibrium temperature near 315 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 12.6, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, Gliese 12 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 Gliese 12 b is an uncommon exoplanet

Gliese 12 b scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Earth-sized, Found by TESS and Orbits a red dwarf — 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.