Archean – Page 2 – My WordPress Site

Hydrothermal Systems May Have Supplied Essential Phosphorus For Early Life -- Tohoku University

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Habitable Zones, Origin & Evolution of Life

Hydrothermal Systems May Have Supplied Essential Phosphorus For Early Life

by Keith CowingJuly 4, 2025July 4, 2025

Phylogenetic distribution of Mo-related genes and their associations with host ecological attributes. Mo-related gene counts and host ecological attributes mapped to a species tree of life25 (left). Tips on the phylogenetic tree are colored by taxonomy (see Supplementary Figure 1 for color legend. Simplified taxonomic clade labels are on the right. Ranked frequencies of Mo-related genes across all genomes in our dataset (n = 1,609) (right). -- biorxiv.org

Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Origin & Evolution of Life

Biological Molybdenum Usage Stems Back To 3.4 Billion Years Ago

by Keith CowingApril 13, 2025April 13, 2025

Methane Cycle During the Archean. High-temperature magmatic processes and low-temperature gas-waterrock reactions, such as Fischer-Tropsch Type (FTT) reactions during serpentinization near hydrothermal vents, were probably the most important Archean abiotic sources of CH4. Additionally, some amount of primordial CH4 could have been released as a result of meteorite impacts. As time passed, different microbial methanogenesis pathways, including hydrogenotrophic, acetoclastic, and methylotrophic, started to contribute to Archean CH4 content. Through photochemical reactions, CH4 was converted to more complex hydrocarbons, creating a hazy atmosphere. Abiotic and biotic oxidation processes were also likely present on Precambrian Earth to consume CH4. Oxidation of CH4 could have happened through processes such as anaerobic sulfate-dependent, metal-dependent, or nitrate/nitrite-dependent anaerobic methanotrophy pathways. Aerobic methanotrophy also contributed to oxidation, likely following the evolution of oxygenic photosynthesis and the availability of O2 as an electron acceptor. -- physics.ao-ph

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Origin & Evolution of Life

Archean Methane Cycling and Life’s Co-Evolution: Intertwining Early Biogeochemical Processes and Ancient Microbial Metabolism

by Keith CowingApril 7, 2025September 18, 2025

Integration time to a 3σ detection for a range of terrestrial atmosphere types on Earth-sized planets orbiting analog nearby targets. Each panel represents a different molecular band, and each color represents a different nearby host star/planet analog. Filled and open circles represent assumed instrumental contrasts of C=10−3 and C=10−4 , respectively, and we assume a total throughput of 10%. A Proxima Centauri b analog (1.3 pc away) is plotted in blue, and a sub-Neptune version of Proxima Centauri b is included for comparison. We may be able to detect several molecules within 100 hours of observing each target, and our Proxima Centauri b analog is the most favorable nearby target for thorough atmospheric characterization. -- astro-ph.EP

Astrochemistry, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy

Simulating The Detectability Of A Range Of Molecules For High-contrast, High-resolution Observations Of Non-transiting Terrestrial Exoplanets

by Keith CowingMarch 13, 2025March 13, 2025

A complex web of interactions between geological features including volcanoes, subsurface mantle, oceans and the atmosphere created the chemical mixture necessary for early life to oxygenate our atmosphere. -- Credit ©2025 Watanabe et al. CC-BY-ND

Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Habitable Zones, Lava / magma ocean / Volcanic Worlds, Microbiology & Virology, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography

Are Volcanoes Behind The Oxygen We Breathe?

by Keith CowingMarch 12, 2025March 12, 2025

Early Earth - Grok via Astrobiology.com

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Fossils & Paleontology, Habitable Zones, Origin & Evolution of Life

Evolution Of The Archean Atmosphere

by Keith CowingOctober 4, 2024October 4, 2024

[L] NASA ID: art002e000192 art002e000192 (April 3, 2026) -- NASA [R] art002e000193 (April 3, 2026) -- NASA

Analog Studies, Astrochemistry, Astrogeology, Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Proxima Centauri

Detectability Simulations of a NIR Surface Biosignature on Proxima Centauri b with Future Space Observatories

by Keith CowingSeptember 11, 2024September 11, 2024

Arctic / Antarctic / Alpine, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Cryobiology, Dale Andersen's Field Reports, Exploration Gear & Tech, Extremeophiles and Extreme Environments, Fossils & Paleontology, Habitable Zones, Icy Worlds, Microbiology & Virology, Robotics/Rovers/UAVs, ROVs/Submersibles/Diving, Water/Hycean Worlds & Oceanography

Microbial Structures In An Antarctic Lake Could Reveal More About How Life Evolved

by Keith CowingJuly 22, 2024July 22, 2024

A sketch of the proposed scenario. Oxidized planetesimals decay to near 1 au, accreting onto proto-Earth and proto-Venus as well as forming Mars. Some oxidized planetesimals and aubrite-like planetesimals remain and will be implanted during the giant planet instability into the asteroid belt as the parent bodies of NC iron meteorites and aubrites, where they join the later-formed chondrites (checkered circles) and C-type asteroids (purple circles) delivered from beyond Jupiter. -- astro-ph.EP

Analog Studies, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Water/Hycean Worlds & Oceanography

Retrievals Applied to a Decision Tree Framework Can Characterize Earthlike Exoplanet Analogs

by Keith CowingJuly 16, 2024July 7, 2024

An example of a simulated spectrum for a Proterozoic Earth–like planet, in which no single feature dominates but absorption from numerous molecules is visible, including O2 and O3. The N2O features (shown in brown) appear at multiple wavelengths beyond 1 μm. Source: Tokadjian et al. (2024); image used unchanged under the CC BY 4.0 license. -- Science Direct

Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exploration Gear & Tech, Fossils & Paleontology, Mapping, Geodesy, Cartography, Microbiology & Virology, Origin & Evolution of Life

Operational Report: Drilling In The Moodies Group of the Barberton Greenstone Belt (BASE – Barberton Archean Surface Environments)

by Keith CowingJune 25, 2024June 25, 2024