Rare exoplanet 37 EP

HD 191939 f

RA 302.0256° · Dec 66.8503° · exoplanet

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Score breakdown

· 5 badges

37 pts · Rare

Rare 46 pts → Epic

Richly packed system +14
Frozen world +8
Multi-planet system +6
Confirmed exoplanet +5
Gas giant +4

Total score 37

9 more points to reach Epic.

Badges

Confirmed exoplanet · +5
Gas giant · +4
Frozen world · +8
Multi-planet system · +6
Richly packed system · +14

Trivia

What makes it special

Frozen world. A deep-frozen world far from its star's warmth.
Packed system. Crammed into a system of five or more planets.

Could we get there?

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

Getting there

Aboard Voyager 1. ≈ 3.1 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 273 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 1748 years in a starship at a tenth of light speed.
Distance. 175 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1851.

Saying hello

Say hello. A radio message and its reply would take 350 years round-trip.

Standing on it

A year here. A full year lasts about 7.9 Earth years.

By the numbers

Size. About 13.2× the width of Earth.
Volume. About 2300 Earths could fit inside it.
Mass. Roughly 915× Earth's mass — about 2.9 Jupiters.
Your weight. You'd weigh about 5.3× 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 6 planets orbiting its star.

Properties

density gcc: 2.19
discovery facility: W. M. Keck Observatory
discovery method: Radial Velocity
dist ly: 174.8486
eccentricity: 0
eq temp k: 125
insolation: 0.0472
mass earth: 915.3458
name: HD 191939 f
orbital period days: 2898
radius earth: 13.2
sys num planets: 6

About HD 191939 f

HD 191939 f is a rare exoplanet. It lies about 174.8 light-years from Earth, has an equilibrium temperature near 125 K, spans roughly 13.2 Earth radii and weighs about 915.35 Earth masses.

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

How to see it

Like any astronomical target, HD 191939 f 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 191939 f is a rare exoplanet

HD 191939 f scores 37 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 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 Richly packed 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.