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Common exoplanet 18 EP

GJ 2126 b

RA 257.3607° · Dec -35.3917° · exoplanet

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Score breakdown

· 3 badges
18 pts · Common
Common 22 pts → Uncommon
  • Eccentric orbit +9
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Eccentric orbit · +9

Trivia

Hard to believe

  • It would float. It is less dense than water. Drop it in a big enough ocean and the whole world would bob on the surface.

What it actually is

  • What it is made of. Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 10.7 you'll want a small backyard telescope.
  • Southern sky. It rides the southern half of the sky — an easier target the further south 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. ≈ 2.2 million years at Voyager 1's speed (17 km/s).

Properties

density gcc
0.903
diameter km
173484.32
discovery facility
La Silla Observatory
discovery method
Radial Velocity
discovery year
2025
dist ly
124.36
eccentricity
0.85
eq temp k
203.08
host star teff
4159
insolation
0.2833
mag
10.7
mass earth
413.1769
name
GJ 2126 b
orbital period days
272.7
radius earth
13.6
semi major au
0.71
spect
M0 V
sys num planets
1
sys num stars
1

About GJ 2126 b

GJ 2126 b is a common exoplanet. It lies about 124.4 light-years from Earth, shines at apparent magnitude 10.7, has spectral type M0 V and has an equilibrium temperature near 203 K.

Lighter than Neptune — a puffed-up ball of hydrogen and helium with no surface anywhere on it to stand on.

How to see it

At apparent magnitude 10.7, a small backyard telescope will bring it into view.

Like any astronomical target, GJ 2126 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 2126 b is a common exoplanet

GJ 2126 b scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Gas giant and Eccentric orbit — 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.