Uncommon exoplanet 27 EP

LP 791-18 d

RA 165.6905° · Dec -16.4064° · exoplanet

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Score breakdown

· 3 badges

27 pts · Uncommon

Uncommon 33 pts → Rare

Earth-sized +16
Multi-planet system +6
Confirmed exoplanet +5

Total score 27

6 more points to reach Rare.

Badges

Confirmed exoplanet · +5
Earth-sized · +16
Multi-planet system · +6

Trivia

Could we get there?

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

Getting there

Aboard Voyager 1. ≈ 1.5 million years at Voyager 1's speed (17 km/s).
Fastest probe ever. ≈ 134.9 thousand years even at the Parker Solar Probe's 192 km/s.
At 10% light speed. ≈ 864 years in a starship at a tenth of light speed.
Distance. 86.4 light-years from Earth.

Look-back time

Look-back time. The light you'd see left around the year 1940.

Saying hello

Say hello. A radio message and its reply would take 173 years round-trip.

Standing on it

A year here. A full year lasts just 2.8 Earth days.

By the numbers

Size. Almost exactly Earth-sized.
Mass. About 0.9× the mass of Earth.
Your weight. You'd weigh about 0.9× your Earth weight standing here.
Temperature. A scorching 122°C on average.

How we found it

Discovery. Found by Spitzer Space Telescope using the transit method.

Cosmic context

Crowded system. One of at least 3 planets orbiting its star.

Properties

density gcc: 4.56
discovery facility: Spitzer Space Telescope
discovery method: Transit
dist ly: 86.4075
eccentricity: 0.0011
eq temp k: 395.5
insolation: 5.83
mass earth: 0.91
name: LP 791-18 d
orbital period days: 2.7548
radius earth: 1.032
sys num planets: 3

About LP 791-18 d

LP 791-18 d is an uncommon exoplanet. It lies about 86.4 light-years from Earth, has an equilibrium temperature near 396 K, spans roughly 1.03 Earth radii and weighs about 0.91 Earth masses.

One of at least 3 planets orbiting its star.

How to see it

Like any astronomical target, LP 791-18 d 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 LP 791-18 d is an uncommon exoplanet

LP 791-18 d scores 27 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 6 points would lift it into a rarer tier.

That score comes from 3 science badges — Confirmed exoplanet, Earth-sized 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.