![Physical and chemical gradients predicted to dictate habitability across depth in the martian subsurface. These include (1) constraints on water; although water activity (aw) gradients are not yet known for Mars, predicted liquid brine stability depends on primary ionic composition with perchlorate-rich brines transitioning into chloride- and sulfate-enriched brines with depth and temperature (Chevrier and Slank, 2024; Stevens and Cockell, 2023). It is important to note that porosity is expected to decrease with depth, which may also influence water availability, with any potential brines increasingly localized to pore spaces and fractures (Michalski et al., 2018). (2) Surface radiation exposure is expected to subside to lower background radionuclide decay around 3–5 m depth. (3) If liquid water is present at depth, chemotrophic microbial communities could utilize the products of water–rock interaction including inorganic electron donors/acceptors and simple abiotic organics. Image created using biorender.com.-- [Astrobiology (Journal)]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Life-Detection.png?resize=1200%2C719&ssl=1)
[Astrobiology (Journal)] Following the Viking experiments in 1976, many of the original inferences of biological metabolism have been replicated via abiotic mechanisms we now know are plausible on Mars’ surface.
Sample Return
Posted inArctic / Antarctic / Alpine
Molecular Evidence For A Relict Marine Community In An Antarctic Dry Valleys Subglacial Brine-fed System
[Nature] The McMurdo Dry Valleys contain a mosaic of specialized microbial habitats structured by strong physical and chemical gradients.
Posted inComets and Asteroids
A JWST Study of Stardust. I. Infrared Spectroscopy of Comet 81P/Wild 2 and Overall Composition
[astro-ph.EP] We report observations of comet 81P/Wild 2, target of the Stardust sample return mission, on UT 2023 March 20 and 24 at a heliocentric distance (rH) of 1.85 au […]
Posted inComets and Asteroids
Gelato: A Mission Concept for Comet Surface Sample Return
[The Planetary Science Journal] Understanding the role of comets in solar system formation and evolution has continued to be a driving question in planetary science. It is believed that comets […]
Posted inSpace Life Science
Assessing The Susceptibility Of Microalgae To Space Conditions Using Stratospheric Balloons
[Scientific Reports via Xmol] Biological exposure experiments under near-space conditions remain limited by the high cost and low accessibility of spaceflight platforms, motivating low-cost analog approaches for initial screening.
Posted inExtremeophiles and Extreme Environments
Small-Scale Mineral And Microbial Heterogeneities Near A Fumarole At The Furnas Hydrothermal Zone On The Azores
[Life (Basel)]. The Azores are characterized by intense volcanic activity, creating unique environments such as fumarole sites, where geothermal gases and high temperatures drive distinct chemical and biological processes.
Posted inAway Teams & Field Reports
Microorganisms Actively Shape Earth’s Ocean Floor
[MARUM]. In August 2023, the German research vessel METEOR set sail on Expedition M192 to the Greek island of Milos with Dr. Solveig Bühring as the chief scientist. The mission […]
Posted inExtremeophiles and Extreme Environments
Rock-eating Fungi Flourish Deep Within Earth
[University of Michigan] Hundreds of feet below Earth’s surface, rocks and water teem with fungi and support complex ecosystems of tiny organisms, according to a University of Michigan study, which […]
Posted inExtremeophiles and Extreme Environments
Assessment Of Saccharomyces Cerevisiae Survival Upon Exposure to Transient High Pressure and Temperature in a High-Intensity Shock Tube for Astrobiology (HISTA)
[bio-protocol] Understanding microbial survival under extreme planetary conditions is critical for astrobiology and stress biology.
Posted inExtremeophiles and Extreme Environments
Comparative Genomics Of Space-resilient Chroococcidiopsis Cyanobacteria Reveals A Core Genetic Repertoire Supporting Extreme Tolerance Towards Desert And Non-Earth Conditions
[FEMS Microbes] Desert cyanobacteria of the Chroococcidiopsis genus, due to their remarkable desiccation and radiation tolerance, are considered model candidates in the field of astrobiology.