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Rare exoplanet 33 EP

HD 4203 c

RA 11.1722° · Dec 20.4484° · exoplanet

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Score breakdown

· 5 badges
33 pts · Rare
Rare 46 pts → Epic
  • Long-period world +10
  • Frozen world +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Gas giant +4
Total score 33

13 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Gas giant · +4
  • Frozen world · +8
  • Long-period world · +10
  • Multi-planet system · +6

Trivia

What makes it special

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

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 4.7 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 414.4 thousand years even at the Parker Solar Probe's 192 km/s.
  • At 10% light speed. ≈ 2654 years in a starship at a tenth of light speed.
  • Distance. 265 light-years from Earth.

Look-back time

  • Look-back time. The light you'd see left around the year 1761.

Saying hello

  • Say hello. A radio message and its reply would take 531 years round-trip.

Standing on it

  • A year here. A full year lasts about 18.3 Earth years.

By the numbers

  • Size. About 13.3× the width of Earth.
  • Volume. About 2353 Earths could fit inside it.
  • Mass. Roughly 690× Earth's mass — about 2.2 Jupiters.
  • Your weight. You'd weigh about 3.9× your Earth weight standing here.
  • Temperature. A frigid -148°C — colder than dry ice.

How we found it

  • Discovery. Found by W. M. Keck Observatory using the radial velocity method.

Cosmic context

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

Properties

density gcc
1.61
discovery facility
W. M. Keck Observatory
discovery method
Radial Velocity
dist ly
265.4241
eccentricity
0.24
eq temp k
124.96
insolation
0.0406
mass earth
689.66
name
HD 4203 c
orbital period days
6700
radius earth
13.3
sys num planets
2

About HD 4203 c

HD 4203 c is a rare exoplanet. It lies about 265.4 light-years from Earth, has an equilibrium temperature near 125 K, spans roughly 13.3 Earth radii and weighs about 689.66 Earth masses.

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

How to see it

Like any astronomical target, HD 4203 c 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 4203 c is a rare exoplanet

HD 4203 c scores 33 points on Spacedle's rarity scale, which places it in the rare tier. Another 13 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 Multi-planet system — 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.