Star system, 41 light-years
TRAPPIST-1 and its seven planets
TRAPPIST-1 b is an exoplanet 1.116 times Earth's width, 41 light-years away.
TRAPPIST-1 is a star of spectral type M8.0 V, 41 light-years from us, with seven known planets. This page takes them one at a time.
Drawn at the system's own scale, every orbit from the Archive's numbers.
What is measured, what is computed, what is imagined.
measured The period, and where the table says so the width and the mass, by the method named in each section.
computed Anything marked computed: the size of an orbit where Kepler's third law corrects the table, the temperature of a bare ball at that distance, the starlight received, and the habitable zone.
imagined The picture is an artist's impression. Nobody has seen the surface of a planet of another star: its colour, clouds and land are not known, and the share picture says so in its corner.
The planets
TRAPPIST-1 b
TRAPPIST-1 b is an exoplanet 1.116 times Earth's width, 41 light-years away.
- Width
- 1.116 × Earth's measured
- Mass
- 1.374 times Earth's measured
- One year
- 1.51083 days measured
- Distance from its star
- 0.01154 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2016. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 b in 3D · The picture is an artist's impression.
TRAPPIST-1 c
TRAPPIST-1 c is an exoplanet 1.097 times Earth's width, 41 light-years away.
- Width
- 1.097 × Earth's measured
- Mass
- 1.308 times Earth's measured
- One year
- 2.42194 days measured
- Distance from its star
- 0.0158 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2016. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 c in 3D · The picture is an artist's impression.
TRAPPIST-1 d
TRAPPIST-1 d is an exoplanet 0.788 times Earth's width, 41 light-years away.
- Width
- 0.788 × Earth's measured
- Mass
- 0.388 times Earth's measured
- One year
- 4.04922 days measured
- Distance from its star
- 0.02227 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2016. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 d in 3D · The picture is an artist's impression.
TRAPPIST-1 e
TRAPPIST-1 e is an exoplanet 0.92 times Earth's width, 41 light-years away.
- Width
- 0.92 × Earth's measured
- Mass
- 0.692 times Earth's measured
- One year
- 6.10101 days measured
- Distance from its star
- 0.02925 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2017. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 e in 3D · The picture is an artist's impression.
TRAPPIST-1 f
TRAPPIST-1 f is an exoplanet 1.045 times Earth's width, 41 light-years away.
- Width
- 1.045 × Earth's measured
- Mass
- 1.039 times Earth's measured
- One year
- 9.20754 days measured
- Distance from its star
- 0.03849 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2017. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 f in 3D · The picture is an artist's impression.
TRAPPIST-1 g
TRAPPIST-1 g is an exoplanet 1.129 times Earth's width, 41 light-years away.
- Width
- 1.129 × Earth's measured
- Mass
- 1.321 times Earth's measured
- One year
- 12.3524 days measured
- Distance from its star
- 0.04683 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2017. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 g in 3D · The picture is an artist's impression.
TRAPPIST-1 h
TRAPPIST-1 h is an exoplanet 0.755 times Earth's width, 41 light-years away.
- Width
- 0.755 × Earth's measured
- Mass
- 0.326 times Earth's measured
- One year
- 18.7729 days measured
- Distance from its star
- 0.06189 au from the Archive
It was found as a small, regular dip in its star's light each time it crosses in front of it in 2017. No habitable zone is computed for its star (a pulsar, a binary or a star outside the formula's range), so none is claimed.
See TRAPPIST-1 h in 3D · The picture is an artist's impression.
The star
- Surface temperature
- 2,566 K
- Width
- 0.1192 × the Sun's
- Mass
- 0.0898 × the Sun's
- Spectral type
- M8.0 V
- Distance
- 41 light-years