TRAPPIST-1 Archives

Gliese 12 b’s estimated size may be as large as Earth or slightly smaller — comparable to Venus in our solar system. This artist’s concept compares Earth with different possible Gliese 12 b interpretations, from one with no atmosphere to one with a thick Venus-like one. CREDIT NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, Venus

Gliese 12 b, A Potentially Habitable Exo-Venus With Earth-like Temperature

by Keith CowingMay 23, 2024May 23, 2024

Astronomers have made the rare and tantalising discovery of an Earth-like exoplanet 40 light-years away that may be just a little warmer than our own world.

Joint constraints on the H2/He abundance and the atmospheric pressure on TRAPPIST-1 b resulting from the sequential fit of the stellar contamination and planetary atmosphere. The color shading illustrates the posterior probability density, where darker colors correspond to higher probabilities. Contours indicate the 1σ, 2σ, and 3σ Bayesian credible regions. The displayed posterior probability is marginalized over the H2O, CH4, CO, CO2, NH3, and N2 abundances. Hydrogen-dominated scenarios with high-altitude clouds are at the top left corner of the plot and cloud-free, volatile-rich, high-mean-molecular-mass atmospheres are at the bottom right. Any hydrogen-rich atmospheres without high-altitude clouds, at the bottom left, are robustly ruled out. The second horizontal axis at the top shows the mean molecular mass representative for a pure H2/H2O atmosphere. -- The Astrophysical Journal Letters

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Press Release

JWST’s First Spectrum Of TRAPPIST-1 b

by Keith CowingMay 18, 2024May 18, 2024

In a solar system called TRAPPIST-1, 40 light years from the sun, seven Earth-sized planets revolve around a cold star.

Artist's view of exoplanet SPECULOOS-3 b orbiting its star. The planet is as big as the Earth, while its star is slightly larger than Jupiter, but much more massive. CREDIT NASA/JPL-Caltech

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

Astronomers Discover A New Earth-sized World Orbiting Ultra-cool Star SPECULOOS-3

by Keith CowingMay 16, 2024May 16, 2024

A new, Earth-sized planet orbiting an ultra-cool red dwarf star, has been detected by an international team of astronomers – just 55 light years away.

An artist’s concept of the exoplanet SPECULOOS-3 b orbiting its red dwarf star. The planet is as big around as Earth, while its star is slightly bigger than Jupiter – but much more massive. Credit: NASA/JPL-Caltech

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

Astronomers Discover Earth-sized Exoplanet Orbiting Ultra-cool Star

by Keith CowingMay 15, 2024May 15, 2024

An international scientific team, with the participation of researchers from the Instituto de Astrofísica de Canarias (IAC), confirms the existence of an Earth-sized planet orbiting an ultra-cold red dwarf located […]

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 […]

TRAPPIST-1

Gliese 12 b, A Potentially Habitable Exo-Venus With Earth-like Temperature

JWST’s First Spectrum Of TRAPPIST-1 b

Astronomers Discover A New Earth-sized World Orbiting Ultra-cool Star SPECULOOS-3

Astronomers Discover Earth-sized Exoplanet Orbiting Ultra-cool Star

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

Curiosity Mars Rover Discovers A Field Of Honeycomb Textures

Viking Science

Constraining The Lives And Times Of Exoplanets Through Evolutionary Bayesian Retrievals

Project Hephaistos — III. Characterizing Anomalous Infrared Sources Identified As Dyson-sphere Candidates

SCoRE: The Surface Composition Of Rocky Exoplanets