Recovery of Lipid Biomarkers in Hot Spring Digitate Silica Sinter as Analogs for Potential Biosignatures on Mars: Results from Laboratory and Flight-Like Experiments.

Digitate siliceous sinter deposits are common in geothermal environments. They form via evaporation and precipitation of cooling silica-rich fluids and passive microbial templating. Increasing interest in these "finger-like" microstromatolitic sinters is related to their morphological and mineralogical resemblance to opaline silica-rich rocks discovered by NASA's Spirit rover in the Columbia Hills, Gusev crater, Mars.

A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations.

Enceladus and Europa, icy moons of Saturn and Jupiter, respectively, are believed to be habitable with liquid water oceans and therefore are of interest for future life detection missions and mission concepts. With the limited data from missions to these moons, many studies have sought to better constrain these conditions. With these constraints, researchers have, based on modeling and experimental studies, hypothesized a number of possible metabolisms that could exist on Europa and Enceladus if these worlds host life.

Astrobiology-Related Virtual Field Trips in Higher Education Settings: A Six-Year Study.

Astrobiology-related laptop-delivered 360-degree immersive Virtual Field Trips (VFTs) are increasingly used in higher education. However, the literature remains sparse on the experiences in approach to pedagogy and what works and what does not in attaining the intended outcomes. Part of the reason for that has been the limitation on the cost of making this educationally promising type of VFT in terms of time and money, but various initiatives are addressing these two limiting factors.

Biogeochemistry of Recently Fossilized Siliceous Hot Spring Sinters from Yellowstone, USA.

Active hot springs are dynamic geobiologically active environments. Heat- and element-enriched fluids form hot spring sinter deposits that are inhabited by microbial and macroscopic eukaryotic communities, but it is unclear how variable heat, fluid circulation, and mineralization within hot spring systems affect the preservation of organic matter in sinters. We present geological, petrographic, and organic geochemical data from fossilized hot spring sinters (<13 Ka) from three distinct hot spring fields of Yellowstone National Park.

Mars Rover Techniques and Lower/Middle Cambrian Microbialites from South Australia: Construction, Biofacies, and Biogeochemistry.

The Perseverance rover (Mars 2020) is equipped with an instrumental and analytical payload capable of identifying a broad range of organic molecules in geological samples. To determine the efficacy of these analytical techniques in recognizing important ecological and environmental signals in the rock record, this study utilized analogous equipment, including gas chromatography/mass spectrometry, Raman spectroscopy, X-ray fluorescence (XRF), Fourier transform infrared spectroscopy, along with macroscopic and petrographic observations, to examine early-middle Cambrian microbialites from the Arrowie Basin, South Australia. Morphological and petrographic observations of these carbonate successions reveal evidence of hypersaline-restricted environments.

Biomolecules from Fossilized Hot Spring Sinters: Implications for the Search for Life on Mars.

Hot spring environments are commonly dominated by silica sinters that precipitate by the rapid cooling of silica-saturated fluids and the activity of microbial communities. However, the potential for preservation of organic traces of life in silica sinters back through time is not well understood. This is important for the exploration of early life on Earth and possibly Mars.