Results 71 to 80 of about 29,535 (220)

Rethinking Seawater Mo Isotope Mass‐Balance and the Sedimentary Mo Record

Paleoceanography and Paleoclimatology, Volume 41, Issue 3, March 2026.
Abstract A lingering misconception is that seawater 98Mo/95Mo ratios should have increased more or less linearly with the oxygenation of Earth's oceans. At the root of this hypothesis is the generalization that oxidizing marine sediments have a stronger affinity for lighter‐mass Mo isotopes than their reducing counterparts.
C. M. Ostrander, O. Dellwig
wiley   +1 more source

Dependence of Biological Activity on the Surface Water Fraction of Planets

, 2019
One of the unique features associated with the Earth is that the fraction of its surface covered by land is comparable to that spanned by its oceans and other water bodies.
Lingam, Manasvi, Loeb, Abraham
core   +1 more source

Investigating the Composition and Metabolic Potential of Microbial Communities in Chocolate Pots Hot Springs

Frontiers in Microbiology, 2018
Iron (Fe) redox-based metabolisms likely supported life on early Earth and may support life on other Fe-rich rocky planets such as Mars. Modern systems that support active Fe redox cycling such as Chocolate Pots (CP) hot springs provide insight into how ...
Nathaniel W. Fortney, Shaomei He, Shaomei He, Brandon J. Converse, Eric S. Boyd, Eric E. Roden   +5 more
doaj   +1 more source

A critical role of heterotrophic bacteria in early diagenesis of carbonates through exopolymer degradation and calcium release

The Depositional Record, Volume 12, Issue 1, February 2026.
Exopolymeric substances (EPS) produced in the photic zone and surface sediments sequester calcium. Below the sediment surface, heterotrophic bacteria degrade EPS, releasing calcium resulting in carbonate precipitation. This process, which continues for millennia deep in the core, is an important sink for atmospheric carbon dioxide.
Pieter T. Visscher, Pierre Boussagol, Raphael Bourillot, Christophe Dupraz, Olivier Braissant, Alan W. Decho, Brendan P. Burns, Richard Allen White III, Paxton Tomko, Emmanuelle Vennin   +9 more
wiley   +1 more source

Motivation, demographics, and engagement during COVID-19 in an astrobiology massive open online course

Physical Review Physics Education Research
Massive open online courses (MOOCs) experienced a resurgence in popularity due to the COVID-19 pandemic. In this work, we studied participants in an astrobiology MOOC offered on Coursera since April 2019.
Skylar Grayson, Molly N. Simon, Sanlyn Buxner, Matthew Wenger, Chris Impey   +4 more
doaj   +1 more source

Polysphaeroides filiformis, a proterozoic cyanobacterial microfossil and implications for cyanobacteria evolution

iScience
Summary: Deciphering the fossil record of cyanobacteria is crucial to understand their role in the chemical and biological evolution of the early Earth.
Catherine F. Demoulin, Marie Catherine Sforna, Yannick J. Lara, Yohan Cornet, Andrea Somogyi, Kadda Medjoubi, Daniel Grolimund, Dario Ferreira Sanchez, Remi Tucoulou Tachoueres, Ahmed Addad, Alexandre Fadel, Philippe Compère, Emmanuelle J. Javaux   +12 more
doaj   +1 more source

Extreme environments in a world of new extremes

Ecosphere, Volume 17, Issue 2, February 2026.
Abstract Extreme environments, whether defined by climate, soils, or disturbance, at landscape or micro‐scales, are prevalent across Earth's surface and have long served as crucibles for ecological and evolutionary insights. Many foundational theories were developed in deserts, cliffs, ultramafic soils, and other harsh systems.
Catherine M. Hulshof, Pablo Tejero Ibarra, Nishanta Rajakaruna, Sara Palacio   +3 more
wiley   +1 more source

The Influence of Stellar Phosphorus On Our Understanding of Exoplanets\n and Astrobiology [PDF]

, 2020
Natalie R. Hinkel, Hilairy E. Hartnett, Patrick Young   +2 more
openalex   +1 more source

PAHs and Astrobiology [PDF]

EAS Publications Series, 2011
In dense molecular clouds, the birthplace of stars and planets, interstellar atoms and molecules freeze onto extremely cold dust and ice particles. These ices are processed by ultraviolet light and cosmic rays forming hundreds of far more complex species, some of astrobiological interest.
openaire   +2 more sources

Ion‐Selective Electrode Robustness to Environmental Conditions Relevant to Spaceflight Missions to the Outer Solar System

Electroanalysis, Volume 38, Issue 2, February 2026.
Future in situ missions to ocean worlds of the outer solar system would benefit from the aqueous chemical measurements provided by ion‐selective electrodes (ISEs). Here, we verify the performance of ISEs after exposure to environments expected during outer Solar System missions, specifically near‐decade scale transit times, anhydrous conditions, low ...
Elizabeth A. Jaramillo, Emmanuelle Despagnet‐Ayoub, Anita Fisher, Richard C. Quinn, Aaron C. Noell   +4 more
wiley   +1 more source