TRAPPIST-1 Archives

This graphic compares data collected by Webb’s NIRSpec (Near-Infrared Spectrograph) with computer models of exoplanet TRAPPIST-1 e with (blue) and without (orange) an atmosphere. Narrow colored bands show the most likely locations of data points for each model. Illustration: NASA, ESA, CSA, STScI, Joseph Olmsted (STScI)

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, TRAPPIST-1

Webb Looks at Earth-Sized, Habitable-Zone Exoplanet TRAPPIST-1 e

by Keith CowingSeptember 15, 2025September 14, 2025

Scientists are in the midst of observing the exoplanet TRAPPIST-1 e with NASA’s James Webb Space Telescope. Careful analysis of the results so far presents several potential scenarios for what […]

Schematic of the TRAPPIST-1 planetary system. The seven known planets are shown orbiting the central star. The semi-transparent green annulus marks the optimistic habitable zone, which contains planets e, f, and g the primary targets of this search. -- astro-ph.IM

Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Intelligence & Language, Interstellar, SETI & Technosignatures, Status Report, TRAPPIST-1

A Deep SETI Search For Technosignatures In The TRAPPIST-1 System With FAST

by Keith CowingSeptember 10, 2025September 10, 2025

The Five-hundred-meter Aperture Spherical Telescope (FAST) is the world’s largest single-dish radio telescope, and the search for extraterrestrial intelligence (SETI) is one of its five key science objectives.

Spectral fits to TRAPPIST-1 e’s stellar-contamination-corrected transmission spectrum. Top: bestfitting forward models for three different partial pressures of N2 and CH4 (solid, dotted, and dashed colored lines) compared to a flat line (dotted black line). Bottom: GP+atmosphere retrievals for the centered log-ratio prior (CLR; blue) and log-uniform priors with a ‘ghost’ background gas (gray) compared to a flat line (dotted black line). All models are plotted binned to the same spectral resolution as the data. The wavelengths of potential CH4 absorption bands are annotated. The corresponding corner plot is in Appendix E. The best-fitting forward models and both retrieval approaches independently identify spectral features tentatively attributed to CH4 features in a potentially N2-rich atmosphere. -- astro-ph.EP

Status Report, TRAPPIST-1

JWST-TST DREAMS: Secondary Atmosphere Constraints for the Habitable Zone Planet TRAPPIST-1 e

by Keith CowingSeptember 9, 2025September 9, 2025

The TRAPPIST-1 system offers one of the best opportunities to characterize temperate terrestrial planets beyond our own solar system. Within the TRAPPIST-1 system, planet e stands out as highly likely […]

White-light TRAPPIST-1 e JWST/NIRSpec PRISM transit light curves. (Top) Datapoints of the transit event (grey; binned at a cadence of 14-seconds) along with the best-fit transit plus systematics model (black; which includes a visit-long slope and a GP; see text for details). The date at which each observation was obtained is indicated at the top of each panel. (Middle) Residuals of the data minus the best-fit light curve model in parts-per-million (ppm); the root-mean-square of the data at this 14-second cadence is indicated for each observation. (Bottom) Light curves at the Hα line (0.656±0.02 µm, in parts per thousand; ppt) at the same cadence as the white-light curves (pale blue points), and binned at 5-minutes (solid blue points); note how a flare is revealed at about −0.25 hr in this light curve as the most likely explanation for the bump in the July 23, 2023 transit event. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

JWST-TST DREAMS: NIRSpec/PRISM Transmission Spectroscopy of the Habitable Zone Planet TRAPPIST-1 e

by Keith CowingSeptember 9, 2025September 9, 2025

TRAPPIST-1 e is one of the very few rocky exoplanets that is both amenable to atmospheric characterization and that resides in the habitable zone of its star — located at […]

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, TRAPPIST-1

There Is No Earth-like Atmosphere On TRAPPIST-1 d

by Keith CowingSeptember 5, 2025September 5, 2025

The exoplanet TRAPPIST-1 d intrigues astronomers looking for possibly habitable worlds beyond our solar system because it is similar in size to Earth, rocky, and resides in an area around […]

Exoplanets under consideration for the Rocky Worlds DDT. Planets above the cosmic shoreline are expected to have lost their atmosphere. The circled exoplanets have already been observed in emission during JWST’s first three cycles. The exoplanets for which the observations concluded there is no atmosphere are in red. We also added the Solar System terrestrial planets. The XUV irradiation is computed from Zahnle & Catling (2017). -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report, TRAPPIST-1

Constraints On The Possible Atmospheres On TRAPPIST-1 b: Insights From 3D Climate Modeling

by Keith CowingSeptember 3, 2025September 18, 2025

JWST observations of the secondary eclipse of TRAPPIST-1 b at 12.8 and 15 microns revealed a very bright dayside. These measurements are consistent with an absence of atmosphere. Previous 1D […]

Range of best-fit phase curve and eclipse models for TRAPPIST-1 b and c. The detrended data are shown with gray dots and binned data with black dots. Red curves show the light curve model for each JWST program that observed TRAPPIST-1 b and c at 15µm using MIRI F1500W; the shading spans the range of models drawn from the posterior distribution of the day flux, night flux and phase offset for planets b and c from Analysis # 1 at 2-σ. The top panel shows the phase curve from GO 3077; the second row displays the five visits from GO 1177 (PI: Greene); and the third row presents the four visits from GO 2304 (PI: Kreidberg), along with a zoom-in on the double occultation observed in GO 3077. The expected transit and eclipse timings for each planet from [19] are shown in vertical dashed and plain lines respectively (purple for b, orange for c, and green for g). -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1

First JWST Thermal Phase Curves Of Temperate Terrestrial Exoplanets Reveal No Thick Atmosphere Around TRAPPIST-1 b and c

by Keith CowingSeptember 3, 2025September 3, 2025

We report JWST/MIRI 15 μm phase curves of TRAPPIST-1 b and c, revealing thermal emission consistent with their irradiation levels, assuming no efficient heat redistribution.

This artist’s concept depicts planet TRAPPIST-1 d passing in front of its turbulent star, with other members of the closely packed system shown in the background. Credit: NASA, ESA, CSA, J. Olmsted (STScI)

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, TRAPPIST-1

Webb Narrows Atmospheric Possibilities For Earth-sized Exoplanet TRAPPIST-1 d

by Keith CowingAugust 13, 2025August 13, 2025

The exoplanet TRAPPIST-1 d intrigues astronomers looking for possibly habitable worlds beyond our solar system because it is similar in size to Earth, rocky, and resides in an area around […]

Joint posterior constraints on the surface partial pressure of key atmospheric absorbers for atmospheric scenarios similar to solar system terrestrials, with N2 as the background gas. The color shadings correspond to the posterior probability mass, and the contours highlight the 68% and 95% confidence regions from the joint retrieval in each case. The absorber in the N2-background atmosphere is labeled in the top right corner of each panel. The dashed-dotted, dashed, and solid sienna lines correspond to an atmospheric surface pressure of 0.1, 1, and 10 bar. We illustrate where typical models of Archean Earth (AE), Modern Earth (ME), and compositions for Titan (T), early Mars (eMa), Mars (Ma), and Venus (V; Encrenaz & Coustenis 2018) approximately lie relative to our constraints for TRAPPIST-1 d. Star markers correspond to specific cloudy cases, where the planet is modeled as either cloudy or cloud-free (for Titan, Modern Earth, and Venus). For the N2-H2O case, we show as a black dotted line the limit of pressures that would be cut off by refraction in a 11 bar atmosphere (10 bar H2O+1 bar N2). For thinner atmospheres, the impact of refraction on atmosphere detectability is even weaker. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1

Strict Limits On Potential Secondary Atmospheres On The Temperate Rocky Exo-Earth TRAPPIST-1 d

by Keith CowingAugust 13, 2025August 13, 2025

The nearby TRAPPIST-1 system, with its seven small rocky planets orbiting a late-type M8 star, offers an unprecedented opportunity to search for secondary atmospheres on temperate terrestrial worlds.

Stellar flares observed in JWST/NIRISS time-series spectroscopy of TRAPPIST-1. Each column shows one flare event during transits of the TRAPPIST-1c or TRAPPIST-1f planets. Tow row: Light curves with the total flux (integrated over the full spectral range and normalized to the mean out-of-transit flux). Colored points indicate pre-flare (green), flare (orange), maximum flare light (red), and post-flare (blue) phases. Green and blue dashed lines mark the average pre- and post-flare flux levels. Middle row: Light curves of the normalized Hα flux. Bottom row: Time-resolved spectrograms (wavelength vs. time) normalized to the pre-flare spectrum. The shaded blue region shows the drop in flux caused by the planetary transit. For comparison, the time axis in all panels are aligned such that t = 0 corresponds to the beginning of the maximum flare light phase. In all four events, the total flux in the post-flare phase is systematically elevated relative to the pre-flare level. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Magnetic Fields, Electromagnetism, bioelectricity,, Press Release, Radiation, Space Weather & Heliophysics, TRAPPIST-1

Flares On TRAPPIST-1 Reveal The Spectrum Of Magnetic Features On Its Surface

by Keith CowingAugust 8, 2025August 8, 2025

TRAPPIST-1 is an M8 dwarf hosting seven known exoplanets and is currently one of the most frequently observed targets of the James Webb Space Telescope (JWST).

TRAPPIST-1

Webb Looks at Earth-Sized, Habitable-Zone Exoplanet TRAPPIST-1 e

A Deep SETI Search For Technosignatures In The TRAPPIST-1 System With FAST

JWST-TST DREAMS: Secondary Atmosphere Constraints for the Habitable Zone Planet TRAPPIST-1 e

JWST-TST DREAMS: NIRSpec/PRISM Transmission Spectroscopy of the Habitable Zone Planet TRAPPIST-1 e

There Is No Earth-like Atmosphere On TRAPPIST-1 d

Constraints On The Possible Atmospheres On TRAPPIST-1 b: Insights From 3D Climate Modeling

First JWST Thermal Phase Curves Of Temperate Terrestrial Exoplanets Reveal No Thick Atmosphere Around TRAPPIST-1 b and c

Webb Narrows Atmospheric Possibilities For Earth-sized Exoplanet TRAPPIST-1 d

Strict Limits On Potential Secondary Atmospheres On The Temperate Rocky Exo-Earth TRAPPIST-1 d

Flares On TRAPPIST-1 Reveal The Spectrum Of Magnetic Features On Its Surface

White Paper On Phototrophic Biosignatures: Research Priorities For The Search For Life On Other Worlds

Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox

A Scalable Path to Astrometric Exomoon Discoveries with the Nautilus Space Observatory

20 Years Later: The ALH 84001 Debate in Context with Viking’s Results. Lessons Learned and Portals Opened

Ocean Planet Research: 31 New Species Discovered in Two Weeks of Deep Sea Exploration