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Exoplanet system · evidence and sources

TRAPPIST-1

Ultra-cool red dwarf with 7 Earth-sized planets, 3 in habitable zone.

Exoplanet Archive · 18 d Position basis, the same label the app shows on the selection card.

Open in Space Time

Every aspect, with its origin

One record per aspect. The origin says what kind of thing each value is; the source says where it came from; the limit says what it cannot tell you.

ObservedCatalogComputedReconstructedIllustrativeUndocumented
Position Catalog

Host star position and distance (archive)

TRAPPIST-1 at RA 23.1 h, Dec -5°, 40.5 light-years, spectral type M8.0 V. Gaia DR3 2635476908753563008.

SourceNASA Exoplanet Archive, Planetary Systems Composite Parameters · record TRAPPIST-1
Retrieved
MethodTAP query: select hostname,pl_name,hd_name,hip_name,tic_id,gaia_dr2_id,gaia_dr3_id,ra,dec,sy_dist,st_teff,st_rad,st_mass,st_lum,st_spectype,pl_orbsmax,pl_orbper,pl_rade,pl…
Position Catalog

TRAPPIST-1 distance

Distance: 40.541 ly.

SourceGaia DR2 · record TRAPPIST-1
Retrieved
Uncertainty+0.061013 / −0.061013 ly
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

Planet orbits (7 confirmed)

TRAPPIST-1 b, TRAPPIST-1 c, TRAPPIST-1 d, TRAPPIST-1 e, TRAPPIST-1 f, TRAPPIST-1 g, TRAPPIST-1 h: semi-major axes and periods come from the archive's composite parameters. Missing eccentricities or inclinations are filled with explicit defaults recorded per parameter in the snapshot (parameterOrigins), never guessed silently.

SourceNASA Exoplanet Archive, Planetary Systems Composite Parameters · record TRAPPIST-1
Retrieved
MethodElliptical two-body orbits driven by the simulation clock; orbital phase at J2000 is a presentation choice unless a transit mid-time is published.
LimitOrbits are drawn enlarged in the system view for visibility (the app labels the scale). Composite parameters mix references; the archive lists them per value.
Orbit Catalog

TRAPPIST-1 b year length

Year length: 1.5108 days.

SourceAgol et al. 2021 · record TRAPPIST-1 b
Retrieved
Uncertainty+0.000006 / −0.000006 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 b orbit radius

Orbit radius: 0.01154 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 b
Retrieved
Uncertainty+0.0001 / −0.0001 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 c year length

Year length: 2.4219 days.

SourceAgol et al. 2021 · record TRAPPIST-1 c
Retrieved
Uncertainty+0.000018 / −0.000018 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 c orbit radius

Orbit radius: 0.0158 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 c
Retrieved
Uncertainty+0.00013 / −0.00013 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 d year length

Year length: 4.0492 days.

SourceAgol et al. 2021 · record TRAPPIST-1 d
Retrieved
Uncertainty+0.000026 / −0.000026 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 d orbit radius

Orbit radius: 0.02227 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 d
Retrieved
Uncertainty+0.00019 / −0.00019 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 e year length

Year length: 6.101 days.

SourceAgol et al. 2021 · record TRAPPIST-1 e
Retrieved
Uncertainty+0.000035 / −0.000035 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 e orbit radius

Orbit radius: 0.02925 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 e
Retrieved
Uncertainty+0.0025 / −0.0025 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 f year length

Year length: 9.2075 days.

SourceAgol et al. 2021 · record TRAPPIST-1 f
Retrieved
Uncertainty+0.000032 / −0.000032 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 f orbit radius

Orbit radius: 0.03849 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 f
Retrieved
Uncertainty+0.00033 / −0.00033 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 g year length

Year length: 12.352 days.

SourceAgol et al. 2021 · record TRAPPIST-1 g
Retrieved
Uncertainty+0.000054 / −0.000054 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 g orbit radius

Orbit radius: 0.04683 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 g
Retrieved
Uncertainty+0.0004 / −0.0004 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 h year length

Year length: 18.773 days.

SourceAgol et al. 2021 · record TRAPPIST-1 h
Retrieved
Uncertainty+0.000214 / −0.000214 days
LimitComposite parameters can use different publications; they need not form one consistent solution.
Orbit Catalog

TRAPPIST-1 h orbit radius

Orbit radius: 0.06189 AU.

SourceAgol et al. 2021 · record TRAPPIST-1 h
Retrieved
Uncertainty+0.00053 / −0.00053 AU
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

Planet sizes and masses

Bulk values come from a composite catalog. Read each parameter record below for its source, limits and calculation status; a catalog entry is not necessarily a measurement.

SourceNASA Exoplanet Archive, Planetary Systems Composite Parameters · record TRAPPIST-1
Retrieved
LimitComposite parameters may combine a measured radius with a mass estimated from a mass-radius relation; the archive flags which.
Physical data Catalog

TRAPPIST-1 b radius

Radius: 1.116 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 b
Retrieved
Uncertainty+0.014 / −0.012 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 b mass

Mass: 1.374 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 b
Retrieved
Uncertainty+0.069 / −0.069 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 b equilibrium temperature

Equilibrium temperature: 397.6 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 b
Retrieved
Uncertainty+3.8 / −3.8 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 c radius

Radius: 1.097 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 c
Retrieved
Uncertainty+0.014 / −0.012 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 c mass

Mass: 1.308 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 c
Retrieved
Uncertainty+0.056 / −0.056 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 c equilibrium temperature

Equilibrium temperature: 339.7 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 c
Retrieved
Uncertainty+3.3 / −3.3 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 d radius

Radius: 0.788 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 d
Retrieved
Uncertainty+0.011 / −0.01 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 d mass

Mass: 0.388 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 d
Retrieved
Uncertainty+0.012 / −0.012 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 d equilibrium temperature

Equilibrium temperature: 286.2 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 d
Retrieved
Uncertainty+2.8 / −2.8 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 e radius

Radius: 0.92 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 e
Retrieved
Uncertainty+0.013 / −0.012 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 e mass

Mass: 0.692 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 e
Retrieved
Uncertainty+0.022 / −0.022 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 e equilibrium temperature

Equilibrium temperature: 249.7 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 e
Retrieved
Uncertainty+2.4 / −2.4 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 f radius

Radius: 1.045 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 f
Retrieved
Uncertainty+0.013 / −0.012 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 f mass

Mass: 1.039 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 f
Retrieved
Uncertainty+0.031 / −0.031 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 f equilibrium temperature

Equilibrium temperature: 217.7 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 f
Retrieved
Uncertainty+2.1 / −2.1 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 g radius

Radius: 1.129 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 g
Retrieved
Uncertainty+0.015 / −0.013 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 g mass

Mass: 1.321 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 g
Retrieved
Uncertainty+0.038 / −0.038 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 g equilibrium temperature

Equilibrium temperature: 197.3 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 g
Retrieved
Uncertainty+1.9 / −1.9 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 h radius

Radius: 0.755 R⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 h
Retrieved
Uncertainty+0.014 / −0.014 R⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 h mass

Mass: 0.326 M⊕.

SourceAgol et al. 2021 · record TRAPPIST-1 h
Retrieved
Uncertainty+0.02 / −0.02 M⊕
LimitComposite parameters can use different publications; they need not form one consistent solution.
Physical data Catalog

TRAPPIST-1 h equilibrium temperature

Equilibrium temperature: 171.7 K.

SourceDucrot et al. 2020 · record TRAPPIST-1 h
Retrieved
Uncertainty+1.7 / −1.7 K
LimitEquilibrium temperature is a model estimate, not a measured surface temperature. Composite parameters can use different publications; they need not form one consistent solution.
Appearance Illustrative

Rendered planet appearance

Each planet's colour, banding, clouds and ice are inferred from its bulk density, equilibrium temperature and insolation by an appearance classifier. No exoplanet in this system has a resolved image.

SourceSpace Time rendering contract
LimitIllustrative. The classifier is deterministic and the same numbers always give the same look.
Description Undocumented

Description and facts

The short description and the fact list are written by the Space Time authors for orientation. They are not quoted from a catalog field and carry no citation of their own.

SourceSpace Time editorial text
LimitBackground reading is linked under Further reading; it is not the source of the displayed numbers.

What is not measured

  • Appearance: a picture, not a measurement. Rendered planet appearance. Illustrative. The classifier is deterministic and the same numbers always give the same look.

Not yet documented

  • Description: Background reading is linked under Further reading; it is not the source of the displayed numbers.

Dataset freshness

Snapshots this page depends on, read from the generated manifests at request time.
DatasetBundle updatedHorizonAutomated
Exoplanet systems (pscomppars)
NASA Exoplanet Archive
Source retrieved:
Confirmed planets only; composite parameters as published at the snapshot Yes, weekly (Trigger.dev)
Trigger.dev → private Blob snapshots
Last successful check: 5 October 2026 · success

Sources cited

Further reading

Wikipedia: TRAPPIST-1 (background only; not the source of the displayed numbers)

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