Rare exoplanet 45 EP

HD 221420 b

RA 353.3319° · Dec -77.3853° · 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. ≈ 1.8 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 158.6 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 1016 years in a starship at a tenth of light speed.
Distance. 102 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1924.

Saying hello

Say hello. A radio message and its reply would take 203 years round-trip.

Standing on it

A year here. A full year lasts about 27.6 Earth years.

By the numbers

Size. About 12× the width of Earth.
Volume. About 1728 Earths could fit inside it.
Mass. Roughly 7278× Earth's mass — about 22.9 Jupiters.
Your weight. You'd weigh about 50.5× your Earth weight standing here.
Density. Denser than solid iron.
Temperature. A frigid -150°C — colder than dry ice.

How we found it

Discovery. Found by Anglo-Australian Telescope using the radial velocity method.

Properties

density gcc: 23.1
discovery facility: Anglo-Australian Telescope
discovery method: Radial Velocity
dist ly: 101.5699
eccentricity: 0.14
eq temp k: 123.49
insolation: 0.0389
mass earth: 7278.2705
name: HD 221420 b
orbital period days: 10090
radius earth: 12
sys num planets: 1

About HD 221420 b

HD 221420 b is a rare exoplanet. It lies about 101.6 light-years from Earth, has an equilibrium temperature near 123 K, spans roughly 12 Earth radii and weighs about 7,278.27 Earth masses.

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

How to see it

Like any astronomical target, HD 221420 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 221420 b is a rare exoplanet

HD 221420 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.