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Common exoplanet 20 EP

LHS 1903 d

RA 107.8658° · Dec 48.3279° · exoplanet

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Score breakdown

· 4 badges
20 pts · Common
Common 22 pts → Uncommon
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Sub-Neptune +5
  • Found by TESS +4
Total score 20

2 more points to reach Uncommon.

Badges

  • Confirmed exoplanet · +5
  • Sub-Neptune · +5
  • Multi-planet system · +6
  • Found by TESS · +4

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 4 planets orbiting its star.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 12.2 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around January — that's when to go looking.

Could we get there?

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

Properties

density gcc
2.09
diameter km
31890.5
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2026
dist ly
116.4106
eccentricity
0.112
eq temp k
442
host star teff
3664
insolation
6.35
mag
12.23
mass earth
5.96
name
LHS 1903 d
orbital period days
12.5663
radius earth
2.5
semi major au
0.086
spect
M
sys num planets
4
sys num stars
1

About LHS 1903 d

LHS 1903 d is a common exoplanet. It lies about 116.4 light-years from Earth, shines at apparent magnitude 12.23, has spectral type M and has an equilibrium temperature near 442 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 12.23, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, LHS 1903 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 LHS 1903 d is a common exoplanet

LHS 1903 d scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 points would lift it into a rarer tier.

That score comes from 4 science badges — Confirmed exoplanet, Sub-Neptune, Multi-planet system and Found by TESS — 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.