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Rare exoplanet 45 EP

HD 188641 b

RA 299.4048° · Dec -37.7449° · exoplanet

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Score breakdown

· 5 badges
45 pts · Rare
Rare 46 pts → Epic
  • Denser than iron +18
  • Long-period world +10
  • Frozen world +8
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 45

1 more point to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10
  • Denser than iron · +18

Trivia

What makes it special

  • Frozen world. A deep-frozen world far from its star's warmth.
  • Heavyweight. Packed denser than solid iron.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 3.7 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 327.7 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 2098 years in a starship at a tenth of light speed.
  • Distance. 210 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1816.

Saying hello

  • Say hello. A radio message and its reply would take 420 years round-trip.

Standing on it

  • A year here. A full year lasts about 39.9 Earth years.

By the numbers

  • Size. About 11.9× the width of Earth.
  • Volume. About 1685 Earths could fit inside it.
  • Mass. Roughly 9333× Earth's mass — about 29.4 Jupiters.
  • Your weight. You'd weigh about 65.9× your Earth weight standing here.
  • Density. Denser than solid iron.
  • Temperature. A frigid -159°C — colder than dry ice.

How we found it

  • Discovery. Found by Multiple Observatories using the radial velocity method.

Properties

density gcc
30.4
discovery facility
Multiple Observatories
discovery method
Radial Velocity
dist ly
209.8484
eccentricity
0.034
eq temp k
114.36
insolation
0.0285
mass earth
9333.0312
name
HD 188641 b
orbital period days
14583.8104
radius earth
11.9
sys num planets
1

About HD 188641 b

HD 188641 b is a rare exoplanet. It lies about 209.8 light-years from Earth, has an equilibrium temperature near 114 K, spans roughly 11.9 Earth radii and weighs about 9,333.03 Earth masses.

A deep-frozen world far from its star's warmth.

How to see it

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 45 points on Spacedle's rarity scale, which places it in the rare tier. Another 1 point would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Gas giant, Frozen world, Long-period world and Denser than iron — 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.

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Sky imagery and survey data courtesy of Aladin Lite & CDS, Strasbourg. Object data from the NASA Exoplanet Archive, JPL Small-Body Database, and the ATNF Pulsar Catalogue.