TRAPPIST-1 Archives

Absorption contributions from different molecules in a potentially inhabited TRAPPIST-1 e spectrum with surface concentrations similar to a Neoproterozoic Earth (Kaltenegger et al. 2020) and a mixing ratio of H2O fixed at 10−2 . Each color represents a molecule (see legend). Error bars illustrate noise based on the SNR, using the CO2 strongest peak as the signal value. -- astro-ph.EP

AI - Data - Apps - Cybernetics, Astrochemistry, Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1

Machine-assisted Classification Of Potential Biosignatures In Earth-like Exoplanets Using Low Signal-to-noise Ratio Transmission Spectra

by Keith CowingApril 5, 2025April 5, 2025

The search for atmospheric biosignatures in Earth-like exoplanets is one of the most pressing challenges in observational astrobiology. Detecting biogenic gases in terrestrial planets requires high resolution and long integration […]

K2-18 b vertical velocity 𝜔 at the 0.01 bar level. Negative (positive) 𝜔 indicates upwards (downwards) motion. The global overturning circulation is clearly visible. Irradiation concentrated on the dayside heats and expands these atmospheric regions, driving upwards motion. There is corresponding subsidence on the nightside. -- astro-ph.EP

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

A New Convection Scheme For GCMs Of Temperate Sub-Neptunes

by Keith CowingFebruary 19, 2025February 19, 2025

Atmospheric characterisation of temperate sub-Neptunes is the new frontier of exoplanetary science with recent JWST observations of possible Hycean world K2-18b.

Surface temperature (straddling 0◦C), total cloud cover (%), net outgoing thermal radiation (W m−2 ), and cloud water content (kg m−2 ) for four of the simulations listed in Table 1. Simulations are displayed from dry (Sim 01: Arid-Venus), semidry 10 m GEL (Sim 02: 10 m-Venus), Earth-like 310 m GEL (Sim 03: 310 m-Venus) and an aquaplanet (Sim 06). Sims 01–03 are 1 bar N2 dominated with 400ppmv CO2. Sim 06 is N2-dominated, but the only greenhouse gas is H2O following Wolf (2017). Cloud coverage is fairly low in Sims 01–02 as expected given limited surface reservoirs and cloud water content (rightmost column), and is much higher for Sims 03 and 06. -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Press Release, TRAPPIST-1, Venus

TRAPPIST-1 d: Exo-Venus, Exo-Earth or Exo-Dead?

by Keith CowingFebruary 10, 2025February 10, 2025

TRAPPIST-1 d is generally assumed to be at the boundary between a Venus-like world and an Earth-like world, although recently published works on TRAPPIST-1 b and c raise concerns that […]

125 flares discovered in CM Draconis, stacked together and aligned to have a peak at 𝑡 = 0.

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Proxima Centauri, Radiation, Space Weather & Heliophysics, Status Report, Stellar Cartography, TRAPPIST-1

Identifying Flare Locations Through Exoplanet Transit Occultations

by Keith CowingJanuary 11, 2025

M dwarfs are the most common stars in the galaxy, with long lifespans, a high occurrence rate of rocky planets, and close-in habitable zones.

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Missions & Hardware, Press Release, Radiation, Space Weather & Heliophysics, TRAPPIST-1

Parker Solar Probe Has Touched The Outer Reaches Of A Star

by Keith CowingDecember 29, 2024December 29, 2024

Editor’s note: The Parker Solar Probe recently conducted a close fly-by of a star – our sun. This is the closest that any human object has ever gotten to any […]

LEFT: Evolution in the period ratios plane. The points are colour-coded according to their time before the close encounter. We note that the system spends almost all of its time very close to its starting location. Green oblique lines correspond the loci of the zeroth-order threeplanet MMRs. The first-order two-planet MMRs, 7:6 and 6:5, are plotted in grey. The second-order resonance 13:11 is plotted in red. Adapted from Petit et al. (2020). RIGHT: Number of resonances covering the period ratios space for equal-mass planets, with masses 10−5 M⊙. At first order, the number of resonances can be compared to the resonance optical depth ρtot. We plot the two-planet circular Hillstability limits (Petit et al. 2018) for both planet pairs in green and the predicted overlap limit for the three-planet MMRs (Eq. 2.7) in blue. Adapted from Petit et al. (2020). -- astro-ph.EP

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

Long-term Stability and Dynamical Spacing of Compact Planetary Systems

by Keith CowingDecember 29, 2024December 28, 2024

Exoplanet detection surveys revealed the existence of numerous multi-planetary systems packed close to their stability limit.

Phase folded JWST/MIRI observations of TRAPPIST-1 b. a. Phase-folded light curve of the secondary eclipse of TRAPPIST-1 b at 12.8 µm, derived from the observations of 5 eclipses as part of GTO 1279 observations. b. Phase-folded light curve of the secondary eclipse of TRAPPIST-1 b at 15 µm, derived from re-analyses of the observations of 5 eclipses as part of GTO 1177. These figures are derived from the “fiducial analysis” described in the Methods. Blue dots corresponds the corrected flux at the original time sampling, black dots shows the 10min binned corrected flux with an error equal to the standard deviation of the points within the bin, and the red curve show the eclipse model. -- astro-ph.EP

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

Combined Analysis of the 12.8 and 15 μm JWST/MIRI Eclipse Observations of TRAPPIST-1 b

by Keith CowingDecember 18, 2024December 18, 2024

The first JWST/MIRI photometric observations of TRAPPIST-1 b allowed for the detection of the thermal emission of the planet at 15 μm, suggesting that the planet could be a bare […]

Outgassed atmospheric composition at model termination for HD 63433 d (top) and TRAPPIST-1 c (bottom), versus mantle 𝑓 O2 (x-axis), simulated with both atmosphere models (y-axis). Pie chars show volatile volume mixing ratios and white numbers show log10 total surface pressure [bar]. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Lava / magma ocean / Volcanic Worlds, Status Report, TRAPPIST-1

Convective Shutdown In The Atmospheres of Lava Worlds

by Keith CowingDecember 18, 2024December 18, 2024

Atmospheric energy transport is central to the cooling of primordial magma oceans. Theoretical studies of atmospheres on lava planets have assumed that convection is the only process involved in setting […]

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

The Light Of TRAPPIST-1 b Reveals New Insights On The Planet’s Nature

by Keith CowingDecember 16, 2024December 16, 2024

New TRAPPIST-1 observations with JWST underscore the complexities of confirming a planet’s atmosphere using only broadband thermal emission data. This insight takes on added significance with the newly approved “Rocky […]

An artist’s illustration of NASA’s James Webb Space Telescope revealing, in the infrared, a population of small main-belt asteroids. Credits: Image: Ella Maru and Julien de Wit

Astrogeology, Astronomy & Telescopes, Comets and Asteroids, Exoplanets, -moons, -comets, Extinction events, Imaging & Spectroscopy, Impact events, Meteorites & Asteroids, Press Release, TRAPPIST-1

The Smallest Asteroids Ever Detected In The Main Belt

by Keith CowingDecember 11, 2024December 11, 2024

The asteroid that extinguished the dinosaurs is estimated to have been about 10 kilometers across. That’s about as wide as Brooklyn. Such a massive impactor is predicted to hit Earth […]