TRAPPIST-1 Archives

Maps of surface temperature (colors) and 430 hPa winds (arrows) for each GCM simulation with all CO2 cases (each column) having independent color bars. The substellar point is located at (0◦ , 0◦ ). The substellar point is hottest at lower obliquities, and the poles are hotter than the equator at higher obliquities. Day-night surface temperature contrasts and resulting planetary-scale atmospheric wave patterns, like Rossby gyres, are more prominent for the cases with less CO2. For the higher obliquity cases the direction of the equatorial wind speed reverses from eastward to westward. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1

The Coupled Impacts of Atmospheric Composition and Obliquity on the Climate Dynamics of TRAPPIST-1e

by Keith CowingMay 13, 2024May 13, 2024

Planets in multi-planet systems are expected to migrate inward as near-resonant chains, thus allowing them to undergo gravitational planet-planet interactions and possibly maintain a non-zero obliquity.

Cumulative fraction of 350 systems that destabilized within 25 Myr. 99 % of the non-resonant systems with properties consistent with the observations were unstable, as opposed to 11 % of systems initialized in a six-planet resonant chain (via a disk migration simulation). Systems in which only a subset of the planets are captured into a resonant chain were also mostly unstable. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Status Report, Stellar Cartography, TRAPPIST-1

The Six-planet Resonant Chain Of HD 110067

by Keith CowingMay 10, 2024May 10, 2024

HD 110067 is the brightest star known to have six transiting planets. Each adjacent pair of planets has a period ratio that is nearly equal to a ratio of small […]

Oxygen retention efficiency as a function of initial water content in TO. Top Row: Interior planets, T1-b, c, and d. Bottom Row: Outer planets, T1-e, f, g, and h. Coloring shows the percentage of simulations at a particular initial water content that fell in a given oxygen retention efficiency bin (e.g., each column corresponds to one initial water content and sums to 100%). Contours are given for the 50th percentile values (solid white lines) and the 1σ confidence region (dashed white lines). -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report, TRAPPIST-1

The Implications of Thermal Hydrodynamic Atmospheric Escape on the TRAPPIST-1 Planets

by Keith CowingMay 7, 2024May 7, 2024

JWST observations of the 7-planet TRAPPIST-1 system will provide an excellent opportunity to test outcomes of stellar-driven evolution of terrestrial planetary atmospheres, including atmospheric escape, ocean loss and abiotic oxygen […]

Shows the CH4 production rate from ecosystem 1 for the 3.8 Ga Earth (dashed) and TRAPPIST-1e (solid) case. The CH4 production rate is split between anoxic H2 (purple) and CO (grey) consumers. the total of these is also shown (green) This plot used simulations with the reduced network. -- astro-ph.EP

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

Biosignatures From Pre-oxygen Photosynthesising Life On TRAPPIST-1e

by Keith CowingApril 18, 2024April 18, 2024

In order to assess observational evidence for potential atmospheric biosignatures on exoplanets, it will be essential to test whether spectral fingerprints from multiple gases can be explained by abiotic or […]

A comparison of simulated transmission spectra for TRAPPIST-1 e modeled with a self-consistent, Earth-like atmosphere. When self-consistent ice and water clouds are included, no significant spectroscopic changes occur to the spectrum. We see small impacts due to clouds in the relatively transparent portion of the atmosphere between 8 – 13 µm, where the clouds reduce the minimum altitude probed from 10 to 12 km. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Retrieved Atmospheres and Inferred Surface Properties for Exoplanets Using Transmission and Reflected Light Spectroscopy

by Keith CowingApril 3, 2024April 3, 2024

Future astrophysics missions will seek extraterrestrial life via transmission and direct imaging observations.

Transmission spectrum of LHS 1140 b. The two transit observations are color coded, i.e., blue for the G235H grating and green for the G395H grating. The models shown are randomly selected solutions from the posterior distributions of Scenario 4 (Table 4, corresponding to N2-H2O atmospheres with deep clouds). We have applied the best-fit offsets to the data. The offset between the two visits is ∼ 50 ppm, while the offset between the two detectors within each of the two visits is negligible (see Figure 4 and Table 5). -- astro-ph.EP

Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

LHS 1140 b Is A Potentially Habitable Water World

by Keith CowingMarch 21, 2024March 21, 2024

LHS 1140 b is a small planet orbiting in the habitable zone of its M4.5V dwarf host. Recent mass and radius constraints have indicated that it has either a thick […]

Fish community on a reef offshore of Hawaii Island. CREDIT Lauren Freeman, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Moon, Press Release, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Moonlight-driven Biological Choruses In Hawaiian Coral Reefs

by Keith CowingMarch 20, 2024November 16, 2024

Editor’s note: Our world is more or less a double planet. Our large Moon creates significant tidal forces that drive much of the way that our oceans circulate and mix. […]

Combined transmission spectrum LHS1140b obtained with NIRISS SOSS on December 1st and 26th 2023 overlaid with HST observations (solid grey points; Edwards et al. 2021). The orange 2-envelope is the best TLS model dominated by facula. The dashed line is the predicted GCM model of the mini-Neptune scenario of Cadieux et al. (2024); this model is excluded at more than 5  (Cadieux et al., in prep). -- astro-ph.EP

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

Do Temperate Rocky Planets Around M Dwarfs have an Atmosphere?

by Keith CowingMarch 20, 2024

Detecting an atmosphere on nearby temperate planets is one of the most important scientific objectives of the Webb mission, an endeavour in practice limited to a handful of well-characterized planets: […]

Contour plot of surface temperature of the simulations, overlapping with arrows indicating the direction and magnitude of the surface wind.. a, b and c show the noAER simulations with pCO2 = 100, 3,000 and 20,000 Pa (pCH4 fixed at 0 Pa). d, e and f show the noAER simulations with CH4/CO2 = 0.02, 0.04 and 0.1 (pCO2 fixed at 20,000 Pa). g, h and i show the AER simulations with CH4/CO2 = 0.1, 0.125 and 0.175 (pCO2 fixed at 3,000 Pa). The liquid-water region, defined as the area with the surface temperature larger than 273 K and can maintain liquid water on the surface, is denoted with a white line. The wind structure of each simulation is also denoted, with the single jet structure denoted as "SJ" and the double jet structure denoted as "DJ". -- astro-ph.EP

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

3D Simulations Of TRAPPIST-1e With Varying CO2, CH4 And Haze Profiles

by Keith CowingMarch 12, 2024March 12, 2024

Using a 3D General Circulation Model, the Unified Model, we present results from simulations of a tidally-locked TRAPPIST-1e with varying carbon dioxide CO2 and methane CH4 gas concentrations, and their […]

Calculated dayside surface temperature matrices for some of the studied planets. Temperatures are presented in Kelvin. N = 1 was considered, since it is not expected that any of these planets have a very thick atmosphere. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Microbiology & Virology, Press Release, Proxima Centauri, Radiation, Space Weather & Heliophysics, TRAPPIST-1

How Habitable are M-dwarf Exoplanets?

by Keith CowingMarch 7, 2024March 7, 2024

How Habitable are M-dwarf Exoplanets? Modeling Surface Conditions and Exploring the Role of Melanins in the Survival of Aspergillus niger Spores Under Exoplanet-like Radiation

TRAPPIST-1

The Coupled Impacts of Atmospheric Composition and Obliquity on the Climate Dynamics of TRAPPIST-1e

The Six-planet Resonant Chain Of HD 110067

The Implications of Thermal Hydrodynamic Atmospheric Escape on the TRAPPIST-1 Planets

Biosignatures From Pre-oxygen Photosynthesising Life On TRAPPIST-1e

Retrieved Atmospheres and Inferred Surface Properties for Exoplanets Using Transmission and Reflected Light Spectroscopy

LHS 1140 b Is A Potentially Habitable Water World

Moonlight-driven Biological Choruses In Hawaiian Coral Reefs

Do Temperate Rocky Planets Around M Dwarfs have an Atmosphere?

3D Simulations Of TRAPPIST-1e With Varying CO2, CH4 And Haze Profiles

How Habitable are M-dwarf Exoplanets?

A Martian Horizon Last Monday Afternoon

Habitable-zone Earths At The Detection Frontier: Measured Completeness And False-alarm Rate Of A Transit Pipeline For The PLATO M-dwarf Sample

A Homogeneous Survey Of JWST MIRI Transmission Spectra Of 10 Exoplanets

Retrieving Ocean Glint Reflectance Signatures From Directly Imaged Earth-like Exoplanets

Analytical Platform (Microsampling, Catapulting, Trapping, and LIBS) for the Characterization of Discrete Domains in Samples of Astrochemical Interest