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Common exoplanet 18 EP

GJ 1289 b

RA 355.7813° · Dec 36.5363° · exoplanet

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Score breakdown

· 3 badges
18 pts · Common
Common 22 pts → Uncommon
  • Orbits a red dwarf +8
  • Confirmed exoplanet +5
  • Sub-Neptune +5
Total score 18

4 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Orbits a red dwarf · +8

Trivia

What it actually is

  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

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 12.5 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.

Getting there

  • Aboard Voyager 1. ≈ 478.7 thousand years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 42.5 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

density gcc
2.56
diameter km
30359.756
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2024
dist ly
27.2388
eccentricity
0
eq temp k
150
host star teff
3296
insolation
0.0754
mag
12.48
mass earth
6.27
name
GJ 1289 b
orbital period days
111.74
radius earth
2.38
semi major au
0.27
spect
M4.5 Ve
sys num planets
1
sys num stars
1

About GJ 1289 b

GJ 1289 b is a common exoplanet. It lies about 27.2 light-years from Earth, shines at apparent magnitude 12.48, has spectral type M4.5 Ve and has an equilibrium temperature near 150 K.

Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.

How to see it

At apparent magnitude 12.48, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, GJ 1289 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 1289 b is a common exoplanet

GJ 1289 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, Sub-Neptune 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.