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Rare exoplanet 38 EP

LP 791-18 c

RA 165.6905° · Dec -16.4064° · exoplanet

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Score breakdown

· 6 badges
38 pts · Rare
Rare 50 pts → Epic
  • Tidally locked +10
  • Orbits a red dwarf +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by TESS +4
Total score 38

12 more points to reach Epic.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Tidally locked · +10
  • Multi-planet system · +6
  • Found by TESS · +4
  • Orbits a red dwarf · +8

Trivia

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Too light to be solid rock and too heavy to be all gas: most likely a deep global ocean or a thick steamy envelope over a rocky core.
  • Crowded system. One of at least 3 planets orbiting its star.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 16.9 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around March — that's when to go looking.

Could we get there?

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

Properties

density gcc
2.56
diameter km
31737.4256
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2019
dist ly
86.4075
eccentricity
0.0001
eq temp k
324.4
host star teff
2960
inclination
89.94
insolation
2.637
mag
16.91
mass earth
7.16
name
LP 791-18 c
orbital period days
4.9899
radius earth
2.488
semi major au
0.0296
spect
M(6.1 +/- 0.7) V
sys num planets
3
sys num stars
1
tidally locked
yes
tidally locked inferred
yes

About LP 791-18 c

LP 791-18 c is a rare exoplanet. It lies about 86.4 light-years from Earth, shines at apparent magnitude 16.91, has spectral type M(6.1 +/- 0.7) V and has an equilibrium temperature near 324 K.

It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.

How to see it

At apparent magnitude 16.91, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, LP 791-18 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 LP 791-18 c is a rare exoplanet

LP 791-18 c scores 38 points on Spacedle's rarity scale, which places it in the rare tier. Another 12 points would lift it into a rarer tier.

That score comes from 6 science badges — Confirmed exoplanet, Sub-Neptune, Tidally locked, Multi-planet system, Found by TESS and Orbits a red dwarf — 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.