Rare exoplanet 38 EP

HD 217786 c

RA 345.7838° · Dec -0.4304° · exoplanet

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Score breakdown

· 5 badges

38 pts · Rare

Rare 46 pts → Epic

Lava world +14
Blasted by starlight +8
Multi-planet system +6
Confirmed exoplanet +5
Sub-Neptune +5

Total score 38

8 more points to reach Epic.

Badges

Confirmed exoplanet · +5
Sub-Neptune · +5
Lava world · +14
Multi-planet system · +6
Blasted by starlight · +8

Trivia

What makes it special

Lava world. Its surface is likely an ocean of molten rock.

Could we get there?

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

Getting there

Aboard Voyager 1. ≈ 3.2 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 282.6 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 1810 years in a starship at a tenth of light speed.
Distance. 181 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1845.

Saying hello

Say hello. A radio message and its reply would take 362 years round-trip.

Standing on it

A year here. A full year lasts just 2.5 Earth days.

By the numbers

Size. About 2.6× the width of Earth.
Volume. About 17.8 Earths could fit inside it.
Mass. About 7.3× the mass of Earth.
Your weight. You'd weigh about 1.1× your Earth weight standing here.
Temperature. Around 1390°C — hotter than a self-cleaning oven.

How we found it

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

Cosmic context

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

Properties

density gcc: 2.26
discovery facility: Multiple Observatories
discovery method: Radial Velocity
dist ly: 180.9667
eccentricity: 0.399
eq temp k: 1663.13
insolation: 1308.8643
mass earth: 7.3101
name: HD 217786 c
orbital period days: 2.5222
radius earth: 2.61
sys num planets: 2

About HD 217786 c

HD 217786 c is a rare exoplanet. It lies about 181 light-years from Earth, has an equilibrium temperature near 1,663 K, spans roughly 2.61 Earth radii and weighs about 7.31 Earth masses.

Its surface is likely an ocean of molten rock.

How to see it

Like any astronomical target, HD 217786 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 217786 c is a rare exoplanet

HD 217786 c scores 38 points on Spacedle's rarity scale, which places it in the rare tier. Another 8 points would lift it into a rarer tier.

That score comes from 5 science badges — Confirmed exoplanet, Sub-Neptune, Lava world, Multi-planet system and Blasted by starlight — 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.