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Epic exoplanet 57 EP

GJ 900 b

RA 353.7526° · Dec 1.6055° · exoplanet

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Score breakdown

· 6 badges
57 pts · Epic
Epic 78 pts → Anomaly
  • Directly imaged +16
  • Two suns in its sky +12
  • Orbits beyond Neptune's distance +12
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 57

21 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Directly imaged · +16
  • Two suns in its sky · +12
  • Orbits beyond Neptune's distance · +12

Trivia

What makes it special

  • Frozen world. A deep-frozen world, too far from its star's warmth for anything to stay liquid.

Hard to believe

  • Denser than iron. It is packed tighter than solid iron — whatever it is made of, it is not ordinary rock.

What it actually is

  • 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 9.6 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 September — that's when to go looking.

Could we get there?

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

Properties

density gcc
10.1
diameter km
158176.88
discovery facility
Multiple Observatories
discovery method
Imaging
discovery year
2024
dist ly
67.8616
eq temp k
1.48
host star teff
3976
insolation
0
mag
9.59
mass earth
3496.1125
multi star system
yes
name
GJ 900 b
radius earth
12.4
semi major au
12000
spect
K7
sys num planets
1
sys num stars
3

About GJ 900 b

GJ 900 b is an epic exoplanet. It lies about 67.9 light-years from Earth, shines at apparent magnitude 9.59, has spectral type K7 and has an equilibrium temperature near 1 K.

A deep-frozen world, too far from its star's warmth for anything to stay liquid.

How to see it

At apparent magnitude 9.59, a small backyard telescope will bring it into view.

Like any astronomical target, GJ 900 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 900 b is an epic exoplanet

GJ 900 b scores 57 points on Spacedle's rarity scale, which places it in the epic tier. Another 21 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Gas giant, Frozen world, Directly imaged, Two suns in its sky and Orbits beyond Neptune's distance — 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.