Dale T. Andersen

TL;DR: In this article, the authors studied the fluorescence properties of fulvic acids isolated from streams and rivers receiving predominantly terrestrial sources of organic material and from lakes with microbial sources, and showed that the ratio of the emission intensity at a wavelength of 450 nm to that at 500 nm, obtained with an excitation of 370 nm, can serve as a simple index to distinguish sources of isolated aquatic fulvic acid.

TL;DR: The paucity of liquid water under stones is consistent with the apparent absence of hypolithic (under-stone) cyanobacteria, the only known primary producers in such extreme deserts.

TL;DR: In this article, the authors studied the behavior of fluid carving the gullies on Mars and found that they were consistent with formation conditions such as now occur on Mars, outside of the temperature-pressure stability regime of liquid water.

TL;DR: Through the study of Mars terrestrial analogues, the habitability conditions for each of these stages, the geochemistry of the surface, and the likelihood for the preservation of organic and inorganic biosignatures are assessed and constrained.

TL;DR: The results suggest that the utilization and cycling of sulfur compounds may play a major role in the energy production and maintenance of microbial communities in these unique, cold environments.