---
title: "TRAPPIST-1e: facts, distance and size – Krillion Space"
description: "TRAPPIST-1e is the fourth of seven Earth-sized planets circling TRAPPIST-1, a small, cool star about 40 light-years away. Size, distance and sourced facts."
url: https://krilion.app/atlas/trappist-1
language: en-US
---

# TRAPPIST-1e

Temperate rocky world. Depth 27 on the Krillion Space voyage, in the Nearby stars.

TRAPPIST-1e is the fourth of seven Earth-sized planets circling TRAPPIST-1, a small, cool star about 40 light-years away. It orbits in the zone where liquid water could exist on the surface if the planet has an atmosphere, which makes it one of the most closely studied worlds beyond the solar system.

![TRAPPIST-1e at depth 27 in Krillion Space, painted by the game (an illustration, not a photograph).](https://krilion.app/assets/atlas/trappist-1.webp)

## Fact sheet

- **Type:** Earth-sized, likely rocky exoplanet in the habitable zone of an ultracool red dwarf
- **Distance:** About 40.7 light-years from the Sun
- **Size:** About 0.92 times Earth's radius and 0.69 times Earth's mass
- **Constellation:** Aquarius
- **Position in the sky:** Right ascension 23h 07m, declination −5° 02′
- **Seeing it from Earth:** Not visible to the naked eye or binoculars: TRAPPIST-1 is a very faint red star in Aquarius that needs a large telescope, and its planets are known only from the dips they cause when crossing the star.
- **On the voyage:** Depth 27, in the Nearby stars section of the route, between Vega and the Pleiades

## Things to know

- TRAPPIST-1e circles its star every 6.1 days at only about 0.03 times the Earth-Sun distance. ([NASA](https://science.nasa.gov/exoplanet-catalog/trappist-1-e/))
- NASA's Spitzer Space Telescope watched the star almost nonstop for 500 hours in 2016, and in 2017 the team announced seven planets, three of them (e, f and g) in the habitable zone. ([NASA](https://science.nasa.gov/missions/hubble/nasa-telescope-reveals-largest-batch-of-earth-size-habitable-zone-planets-around-single-star/))
- The star is so dim that it gives off only about 0.05% of the Sun's energy, and the system is named after TRAPPIST, a small telescope in Chile that found its first planets. ([NASA](https://science.nasa.gov/solar-system/10-things-all-about-trappist-1/))
- Webb's first four transit observations of planet e, published in 2025, make an original hydrogen-rich atmosphere or a thick carbon-dioxide atmosphere unlikely, but a thinner secondary atmosphere is still possible. ([NASA](https://science.nasa.gov/missions/webb/nasa-webb-looks-at-earth-sized-habitable-zone-exoplanet-trappist-1-e/))
- Like its siblings, TRAPPIST-1e is thought to be tidally locked, with one side always facing its star. ([NASA](https://science.nasa.gov/missions/webb/nasa-webb-looks-at-earth-sized-habitable-zone-exoplanet-trappist-1-e/))

## Sources

- [NASA Science – TRAPPIST-1 e (exoplanet catalog)](https://science.nasa.gov/exoplanet-catalog/trappist-1-e/)
- [NASA Science – NASA Telescope Reveals Largest Batch of Earth-Size, Habitable-Zone Planets Around Single Star](https://science.nasa.gov/missions/hubble/nasa-telescope-reveals-largest-batch-of-earth-size-habitable-zone-planets-around-single-star/)
- [NASA Science – NASA Webb Looks at Earth-Sized, Habitable-Zone Exoplanet TRAPPIST-1 e](https://science.nasa.gov/missions/webb/nasa-webb-looks-at-earth-sized-habitable-zone-exoplanet-trappist-1-e/)

## On the route

- Previous landmark: [Vega](https://krilion.app/atlas/vega)
- Next landmark: [Pleiades](https://krilion.app/atlas/pleiades)
- [The whole Star Atlas](https://krilion.app/atlas)
- [Fly the voyage yourself](https://krilion.app/d/): every right answer warps your ship one stop deeper.