Atmospheres, Climate, Weather Archives

Top: Abundance and temperature-pressure profiles for a 3 M⊕, 600 K equilibrium temperature planet, with 0.1% soot, orbiting an M-dwarf star. Even under the harsh UV irradiation environment of the host star, high abundances of methane (thick brown line) persist to high altitude and low pressure. A combination of methane photolysis in the upper atmosphere, vertical mixing, and thermochemistry give rise to significant quantities of higher-order hydrocarbons such as C2H2, C2H4, and C2H6, Subsequent photolysis and polymerization reactions result in the formation of hydrocarbon haze (thick dashed red line). Bottom: The resulting transmission spectrum (orange line) of this planet is shaped considerably by haze with some strong methane features permeating through the haze at longer wavelengths. The teal line shows the transmission spectrum of the same planet but with the haze opacity artificially removed, while the transparent colored line shows these data at a spectral resolution of R=1,000. -- astro-ph.EP

Astrochemistry, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Status Report, Water/Hycean Worlds & Oceanography

Exoplanet Volatile Carbon Content as a Natural Pathway for Haze Formation

by Keith CowingMay 9, 2023May 9, 2023

We explore terrestrial planet formation with a focus on the supply of solid-state organics as the main source of volatile carbon.

Fraction of simulations that lead to an observable moon (warmer than 270K (Section 3)) as a function of its orbital semi-major axis and eccentricity of the moon. -- astro-ph.EP

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

Tidally Heated Exomoons Around ε Eridani b: Observability And Prospects For Characterization

by Keith CowingMay 7, 2023May 7, 2023

Exomoons are expected to orbit gas giant exoplanets just as moons orbit solar system planets. Tidal heating is present in solar system satellites and it can heat up their interior […]

Simulated emission spectra of TRAPPIST-1 c with MIRI photometric filter mean fluxes for water and CO2 atmospheres, obtained with the high-resolution, k-correlated MSEIRADTRAN model. Color boxes indicate the wavelength ranges of the different filters. — astro-ph.EP

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

Interior-atmosphere Modelling To Assess The Observability Of Rocky Planets With JWST

by Keith CowingMay 3, 2023May 3, 2023

Super-Earths present compositions dominated by refractory materials. However, there is a degeneracy in their interior structure between a planet with no atmosphere and a small Fe content, and a planet […]

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

Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable Zone Exoplanets

by Keith CowingMay 1, 2023November 16, 2024

Molecular oxygen is a strong indicator of life on Earth, and may indicate biological processes on exoplanets too.

Comparison between sources and sinks of H2 on rocky planets around M dwarfs. The grey areas show the range of escape rates depending on the type of the host star. The dark grey area is for a planet that locates at the 1-AU equivalent distance, while the light grey area is for a planet that locates 2.6 times farther away (i.e., receiving 7 times less irradiation). The outgassing rates encapsulate the plausible range from a highly reduced mantle (informed by Figure 1), with the lower bound corresponding to xH = 0.005 wt % and t −1 scaling, and the higher bound corresponding to xH = 0.02 wt % and t −2 scaling. The rate of serpentinization is a very generous upper limit (Section 4). -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones

Narrow Loophole for H2-dominated Atmospheres On Habitable Rocky Planets Around M Dwarfs

by Keith CowingApril 27, 2023April 27, 2023

Habitable rocky planets around M dwarfs that have H2-dominated atmospheres, if they exist, would permit characterizing habitable exoplanets with detailed spectroscopy using JWST, owing to their extended atmospheres and small […]

Distribution of the currently detected planets with the conservative and optimistic habitable zones as a function of stellar temperature of the host star and the flux received by the planet. The flux received is normalized to the Earth one. This plot is regularly updated and produced by the planetary habitability laboratory at the university of Puerto Rico www.phl.upr.edu -- astro-ph.EP

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

Prospects For The Characterization Of Habitable Planets

by Keith CowingApril 24, 2023April 27, 2023

With thousands of exoplanets now identified, the characterization of habitable planets and the potential identification of inhabited ones is a major challenge for the coming decades.

Mixing ratios for the major species in the Archean Earth-like (ARE) atmospheres and temperature profiles. Each line represents a self-consistent Earth-like atmosphere orbiting a stellar host. Earlier-type M dwarf hosts are lighter and later-type M dwarf hosts are darker. The dashed blue line represents profiles for the Earth orbiting the Sun for comparison. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy

There’s More To Life Than O2: Simulating the Detectability Of A Range Of Molecules For Ground-based high-resolution Spectroscopy Of Transiting Terrestrial Exoplanets

by Keith CowingApril 24, 2023April 27, 2023

Within the next decade, atmospheric O2 on Earth-like M dwarf planets may be accessible with visible–near-infrared, high spectral resolution extremely large ground-based telescope (ELT) instruments.

Climatic elements on three planets. (a)–(c) Temporal- and zonal-mean temperature (color shading) and zonal-mean zonal winds (contour lines) on Earth, on the rapidly rotating tidally locked terrestrial planet, and on the slowly rotating tidally locked terrestrial planet; (d)–(f) same as (a)–(c) but for deviations of temporal- and zonal-mean geopotential height from the global means (color shading), and mass stream functions (contour lines, in units of 1010 kg s−1 ). Note that the ranges of color bars in panels (d), (e), and (f) are different. Panels (a), (b), (d) and (e) are shown in the standard coordinates, and (c) and (f) are shown in the tidally locked coordinates. SP and AP are the substellar point and the antistellar point, respectively. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones

Lorenz Energy Cycle: Another Way to Understand the Atmospheric Circulation on Tidally Locked Terrestrial Planets

by Keith CowingApril 24, 2023April 27, 2023

In this study, we employ and modify the Lorenz energy cycle (LEC) framework as another way to understand the atmospheric circulation on tidally locked terrestrial planets.

Top panel: example wavelength sector showing the model contribution from CO only. The model is shown at simulated resolution (grey, sampled every ˚Angstrom) and after being convolved with the observed point spread function and rebinned onto the detector’s wavelength grid (black). Middle panel: visualisation of our method for detecting CO sub-band structure. Red and blue portions indicate wavelengths that are in-band or out-of-band, respectively. Note these wavelength selections are refined in Figure 4. Bottom panel: model contributions per molecule, where H2O is the only significant molecular absorber in this wavelength sector other than CO. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets

Detection of Carbon Monoxide’s 4.6 Micron Fundamental Band Structure In WASP-39b’s Atmosphere With JWST NIRSpec G395H

by Keith CowingApril 24, 2023April 27, 2023

Carbon monoxide (CO) is predicted to be the dominant carbon-bearing molecule in giant planet atmospheres, and, along with water, is important for discerning the oxygen and therefore carbon-to-oxygen ratio of […]

Poynting flux divergence in (a) the bow shock nose and (b) magnetopause reconnection regions. Simulation with southward IMF orientation, |B|IMF = 30 nT and Pd = 1.2 nPa. Black lines indicate the region of the bow shock (n > 20 cm−3 ), the red lines the exoplanet magnetic field lines and the pink iso-surface the reconnection region in the XZ plane (|B| < 5 nT). -- -astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Exoplanets, -moons, -comets, Habitable Zones, Radiation, Space Weather & Heliophysics, Water/Hycean Worlds & Oceanography

MHD Study Of Extreme Space Weather Conditions For Exoplanets With Earth-like Magnetospheres: On Habitability Conditions And Radio-emission

by Keith CowingApril 18, 2023April 27, 2023

The present study aims at characterizing the habitability conditions of exoplanets with an Earth-like magnetosphere inside the habitable zone of M stars and F stars like tau Boo, caused by […]

Atmospheres, Climate, Weather

Exoplanet Volatile Carbon Content as a Natural Pathway for Haze Formation

Tidally Heated Exomoons Around ε Eridani b: Observability And Prospects For Characterization

Interior-atmosphere Modelling To Assess The Observability Of Rocky Planets With JWST

Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable Zone Exoplanets

Narrow Loophole for H2-dominated Atmospheres On Habitable Rocky Planets Around M Dwarfs

Prospects For The Characterization Of Habitable Planets

There’s More To Life Than O2: Simulating the Detectability Of A Range Of Molecules For Ground-based high-resolution Spectroscopy Of Transiting Terrestrial Exoplanets

Lorenz Energy Cycle: Another Way to Understand the Atmospheric Circulation on Tidally Locked Terrestrial Planets

Detection of Carbon Monoxide’s 4.6 Micron Fundamental Band Structure In WASP-39b’s Atmosphere With JWST NIRSpec G395H

MHD Study Of Extreme Space Weather Conditions For Exoplanets With Earth-like Magnetospheres: On Habitability Conditions And Radio-emission

Astrobiology Graduate Conference (AbGradCon26) Update

Mars Curiosity Reaches 1-Kilometer Elevation Gain

Dragonfly Gets Wired Up While Titan Landing Area Is Named

Amplified Cooling Of Snowball Earth From A Salt-albedo Feedback

Prebiotic Cationic Amino Acids Support Formation Of An Ancient Protein Fold