Nitrogen (N) plays a crucial role in controlling biological productivity. However, it remains unknown how Earth’s earliest ecosystems accessed bioavailable forms of nitrogen.
Abiotic
Posted inBiosignatures & Paleobiology, Enceladus, Europa, Habitable Zones, Icy Worlds, Press Release, Water/Hycean Worlds & Oceanography
A Framework For Evaluating Biosignature Potential Against The Abiotic Baseline On Ocean Worlds
Ocean worlds are considered as targets for life detection missions because they meet several key requirements for habitability. However, identifying potential life on other worlds requires observing clear and unambiguous […]
![Selected examples of different chemically oscillating reactions (COR) with patterns produced during the decarboxylation of malonic acid [1 M] using a solution of sodium bromate [1 M], sulfuric acid [0.33 M], sodium bromide [1 M], and phenanthroline ferrous sulfate [0.025 M]. (A) Spot proliferation pattern in a 10 cm diameter petri dish. (B) A few spots of different sizes formed within half a minute. (C) Pairs of images of a COR in a petri dish with insets taken five seconds apart showing the radial diffusion of circularly concentric spots. (D) Spots spanning from sub-millimeter (white arrows) to centimeter sizes. (E) Twinned circularly concentric spots (white dashed line shows the twin plane). A few bubbles of CO2 produced by the reaction can be seen. (F) Circularly concentric spot with short color gradients in laminations. (G) Circularly concentric spot with long color gradients in laminations. (H) Circularly concentric spot with dozens of laminations and CO2 bubbles, formed later (at ∼26 min) during another reaction. -- GeoScience World](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/01/Authigenic-biosignatures-of-microbial.png?resize=1200%2C718&ssl=1)
Posted inBiogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Fossils & Paleontology, Microbiology & Virology, Origin & Evolution of Life, Status Report
Authigenic Biosignatures Of Microbial Biomass Preserved As Carbonate Ooids Formed By Abiotic Chemically Oscillating Reactions Throughout Earth History
Ooids are small spheroidal carbonate grains that have circularly concentric and radially aligned crystals. Oolitic carbonates are commonly associated with fossils or organic matter, which has led to hypothetical formation […]
Posted inAstrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Status Report
Astrochemistry: Abiotic Origin Of Citric Acid Cycle Intermediates
The molecular framework for protometabolism-chemical reactions in a prebiotic environment preceding modern metabolism-has remained unknown in evolutionary biology.
Posted inAI - Data - Apps - Cybernetics, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Status Report
Laminae as Structural Biosignatures in NASA’s Life Detection Knowledge Base
Laminae are millimeter-scale features in rocks created by physiochemical processes that can be influenced by the presence and activities of communities of organisms that occur as biofilms and microbial mats.
Posted inAstrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Exoplanets, -moons, -comets, Icy Worlds, Imaging & Spectroscopy, Status Report
Evidence For Abiotic Dimethyl Sulfide In Cometary Matter
Technological progress related to astronomical observatories such as the recently launched James Webb Space Telescope (JWST) allows searching for signs of life beyond our Solar System, namely in the form […]
Posted inAstrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Status Report
Open-Ended Versus Bounded Evolution: Mineral Evolution As A Case Study
To what extent are natural evolving systems limited in their potential diversity (i.e., “bounded”) versus unrestricted (“open-ended”)? Minerals provide a quantitative model evolving system, with well documented increases in mineral […]
Posted inBiochemistry & Organic Chemistry, Origin & Evolution of Life, Press Release
Metabolic Homeostasis And Growth In Abiotic Cells
Metabolism constitutes the core chemistry of life. How it began on the early Earth and whether it had a cellular origin is still uncertain.
Posted inAstrochemistry, Biogeochemical Cycles & Geobiology, Press Release
New Abiotic Pathway For The Formation Of Oxygen
Oxygen plays a crucial role for all living organisms on Earth.
Posted inAstronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release
Oxygen False Positives On Habitable Zone Planets Around Sun-Like Stars
Oxygen is a promising exoplanet biosignature due to the evolutionary advantage conferred by harnessing starlight for photosynthesis, and the apparent low likelihood of maintaining oxygen-rich atmospheres without life.