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Uncommon exoplanet 31 EP

GJ 849 b

RA 332.4230° · Dec -4.6408° · exoplanet

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Score breakdown

· 5 badges
31 pts · Uncommon
Uncommon 34 pts → Rare
  • Frozen world +8
  • Orbits a red dwarf +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 31

3 more points to reach Rare.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Multi-planet system · +6
  • Orbits a red dwarf · +8

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

  • 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.
  • Crowded system. One of at least 2 planets orbiting its star.

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 10.4 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 August — that's when to go looking.

Properties

density gcc
0.581
diameter km
177311.18
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
discovery year
2006
dist ly
28.7036
eccentricity
0.029
eq temp k
73.63
host star teff
3467
insolation
0.0048
mag
10.41
mass earth
283.8208
name
GJ 849 b
orbital period days
1925.31
radius earth
13.9
semi major au
2.32
spect
M3.5
sys num planets
2
sys num stars
1

About GJ 849 b

GJ 849 b is an uncommon exoplanet. It lies about 28.7 light-years from Earth, shines at apparent magnitude 10.41, has spectral type M3.5 and has an equilibrium temperature near 74 K.

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

How to see it

At apparent magnitude 10.41, a small backyard telescope will bring it into view.

Like any astronomical target, GJ 849 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 849 b is an uncommon exoplanet

GJ 849 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 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Multi-planet system 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.