◀ D:\SPACE · ALL WORLDS

D:\SPACE\TRAPPIST_1_E>

SELECTED WORLD

TRAPPIST-1 e

TRAPPIST-1 · M8.0 V host star · cool red dwarf · main sequence

[ TRAPPIST_1_E.IMG ]
VIEW 1 · ON THE SURFACE
1 / 2
Artist’s impression of TRAPPIST-1 e: VIEW 1 · ON THE SURFACE
VIEW 1 · ON THE SURFACE · Artist’s impression. No surface has been seen.
USE ◀ ▶ TO SEE THE OTHER VIEWS · OR SWIPE
40.5 light-years from Earth
[ FACTS.DAT ]
Right ascension / declination346.626° / -5.043°J2000 / ICRS
Gravity0.82 × Earthderived from measured mass + radius
Year6.1 days
From its star0.0293 AUabout 4.4 million km
Stars in the system1 star7 known planets in system
Stars this world orbits1 starOrbits TRAPPIST-1
Day and nightLikely synchronous spinProbably spins once per orbit, keeping one hemisphere in permanent day and the other in permanent night. Heuristic: likely at ≤0.25 AU, uncertain to 0.50 AU, probably not beyond; rotation is not directly measured.
[ TEMP.EST ]MODELLED, NOT MEASURED
Host star≈2,600 Ktypical M8.0 V · 0.12 Sun radii
No atmosphere232 K · -41°C30% reflective · heat shared
Earth-like air265 K · -8°CBaseline plus 33°C

Star temperature and orbital distance set incoming energy, but stellar size is also required. This calculation uses a typical radius for the listed spectral type, 30% reflectivity and even heat redistribution. It is not a ground-temperature forecast: air, clouds, oceans and surface reflectivity could move the result by tens to hundreds of degrees. A likely synchronous spin also means the permanent day and night sides would not share one ground temperature.

[ STARLIGHT.SPC ]VISIBLE LIGHT ONLY

The marker above the bar is a typical temperature for this star’s class. The line below is Earth’s Sun.

red-orange

TRAPPIST-1 is class M8.0 V. Its visible daylight would be dim and strongly red-orange; most of its energy is infrared.

Representative lit-side geometry only. On a locked world, the star’s real elevation would depend on where you stand.

[ GROUND.TXT ]STILL INFERENCE

Most plausible case. The temperate TRAPPIST world most often compared with Earth. Radius 0.92 and mass 0.69 Earth, so gravity is about 82% of Earth’s, measured. It receives about 65% of Earth’s light. The star spans about 2.2°. Dark rock under that huge red disk, frost toward the night side, and a possible slush eyeball under the star. Transmission spectra so far have not shown a thick hydrogen sky.

Dry case. A red desert of rock and dust, ice on the night side only. Lower gravity than Earth, so dunes would be easier to lift.

Thick-air case. A nitrogen or CO₂ sky could hide the ground under cloud or haze. A hydrogen envelope is disfavored by the mass and the spectra.

Walking. About 18% lighter than Earth, measured. Planets d and f would each look about as wide as the Moon when closest. The daylight is dim, red, and infrared-heavy, under a star five times wider than the Sun looks from Earth.

Based on: Agol et al. 2021; Teff 2566 K, S 0.65, Rp 0.92, Mp 0.69, a 0.029 AU

[ ORBIT.SYS ]7 KNOWN · ALL SHOWN
100% · Above 30°

TRAPPIST-1 e circles TRAPPIST-1. Also shown: TRAPPIST-1 b, TRAPPIST-1 c, TRAPPIST-1 d, TRAPPIST-1 f, TRAPPIST-1 g, TRAPPIST-1 h, each on its NASA-catalogued orbit. Use Higher and Lower to move your viewpoint above, through and below the orbital plane, and − / + to zoom. Orbit shapes and spacing are schematic.

[ SOURCES.TXT ]

Positions, distances, and system parameters come from the NASA Exoplanet Archive composite table, queried 25 Sep 2026. GJ 273 b uses the parallax in that row, 12.4 light-years. The 45 worlds follow Bohl, Lawrence, Lowry, and Kaltenegger.