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Rare exoplanet 43 EP

GJ 393 b

RA 157.2289° · Dec 0.8378° · exoplanet

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Score breakdown

· 4 badges
43 pts · Rare
Rare 50 pts → Epic
  • Earth-sized +16
  • Nearby (<25 ly) +12
  • Tidally locked +10
  • Confirmed exoplanet +5
Total score 43

7 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Nearby (<25 ly) · +12
  • Earth-sized · +16
  • Tidally locked · +10

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 9.7 you'll want a small backyard telescope.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around February — that's when to go looking.

Could we get there?

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

Properties

density gcc
5.87
diameter km
14924.754
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2021
dist ly
22.9336
eq temp k
485
host star teff
3579
insolation
9.21
mag
9.65
mass earth
1.71
name
GJ 393 b
orbital period days
7.0268
radius earth
1.17
semi major au
0.054
spect
M2.0 V
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About GJ 393 b

GJ 393 b is a rare exoplanet. It lies about 22.9 light-years from Earth, shines at apparent magnitude 9.65, has spectral type M2.0 V and has an equilibrium temperature near 485 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 9.65, a small backyard telescope will bring it into view.

Like any astronomical target, GJ 393 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 393 b is a rare exoplanet

GJ 393 b scores 43 points on Spacedle's rarity scale, which places it in the rare tier. Another 7 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Nearby (<25 ly), Earth-sized 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.