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Rare exoplanet 35 EP

HD 188641 b

RA 299.4048° · Dec -37.7449° · exoplanet

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Score breakdown

· 5 badges
35 pts · Rare
Rare 50 pts → Epic
  • Long-period world +10
  • Frozen world +8
  • Orbits a Sun-like star +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 35

15 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10
  • Orbits a Sun-like star · +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

  • 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. 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 7.3 it is just past naked-eye reach — ordinary binoculars will pull it in.
  • 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 July — that's when to go looking.

Could we get there?

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

Properties

density gcc
30.4
diameter km
151798.78
discovery facility
Multiple Observatories
discovery method
Radial Velocity
discovery year
2022
dist ly
209.8484
eccentricity
0.034
eq temp k
114.36
host star teff
5897.32
inclination
49.245
insolation
0.0285
mag
7.34
mass earth
9333.0312
name
HD 188641 b
orbital period days
14583.8104
radius earth
11.9
semi major au
12.027
sys num planets
1
sys num stars
1

About HD 188641 b

HD 188641 b is a rare exoplanet. It lies about 209.8 light-years from Earth, shines at apparent magnitude 7.34, has an equilibrium temperature near 114 K and spans roughly 11.9 Earth radii.

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

How to see it

At apparent magnitude 7.34, it is an easy target for binoculars.

Like any astronomical target, HD 188641 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 HD 188641 b is a rare exoplanet

HD 188641 b scores 35 points on Spacedle's rarity scale, which places it in the rare tier. Another 15 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Long-period world and Orbits a Sun-like star — 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.