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Uncommon exoplanet 31 EP

GJ 3988 b

RA 255.8504° · Dec 51.4090° · exoplanet

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Score breakdown

· 4 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Tidally locked +10
  • Super-Earth +8
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
Total score 31

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Super-Earth · +8
  • Tidally locked · +10
  • Orbits a red dwarf · +8

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.
  • What it is made of. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.

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 13.6 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 June — 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. ≈ 568 thousand years at Voyager 1's speed (17 km/s).

Properties

density gcc
3.85
diameter km
22195.788
discovery facility
Calar Alto Observatory
discovery method
Radial Velocity
discovery year
2023
dist ly
32.3237
eccentricity
0
eq temp k
348
host star teff
3273
insolation
2.45
mag
13.627
mass earth
3.69
name
GJ 3988 b
orbital period days
6.9442
radius earth
1.74
semi major au
0.0405
spect
M4.5 V
sys num planets
1
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About GJ 3988 b

GJ 3988 b is an uncommon exoplanet. It lies about 32.3 light-years from Earth, shines at apparent magnitude 13.63, has spectral type M4.5 V and has an equilibrium temperature near 348 K.

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 13.63, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, GJ 3988 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 3988 b is an uncommon exoplanet

GJ 3988 b scores 31 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 3 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Super-Earth, Tidally locked 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.