Planetary Protection Knowledge Gap Closure Enabling Crewed Missions to Mars.

As focus for exploration of Mars transitions from current robotic explorers to development of crewed missions, it remains important to protect the integrity of scientific investigations at Mars, as well as protect the Earth's biosphere from any potential harmful effects from returned martian material. This is the discipline of planetary protection, and the Committee on Space Research (COSPAR) maintains the consensus international policy and guidelines on how this is implemented. Based on National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) studies that began in 2001, COSPAR adopted principles and guidelines for human missions to Mars in 2008.

Nutrients mediate caffeine inhibition of Escherichia coli.

The consumption of coffee and other caffeinated drinks is increasingly popular across the globe. In the United States, 90% of adults consume at least one caffeinated beverage a day. While caffeine consumption of up to 400 mg/d is not generally associated with negative effects on human health, the impact of caffeine on the gut microbiome and individual gut microbiota remains unclear.

Mars Extant Life: What's Next? Conference Report.

On November 5-8, 2019, the "Mars Extant Life: What's Next?" conference was convened in Carlsbad, New Mexico. The conference gathered a community of actively publishing experts in disciplines related to habitability and astrobiology. Primary conclusions are as follows: A significant subset of conference attendees concluded that there is a realistic possibility that Mars hosts indigenous microbial life.

Report of the Joint Workshop on Induced Special Regions.

The Joint Workshop on Induced Special Regions convened scientists and planetary protection experts to assess the potential of inducing special regions through lander or rover activity. An Induced Special Region is defined as a place where the presence of the spacecraft could induce water activity and temperature to be sufficiently high and persist for long enough to plausibly harbor life. The questions the workshop participants addressed were: (1) What is a safe stand-off distance, or formula to derive a safe distance, to a purported special region? (2) Questions about RTGs (Radioisotope Thermoelectric Generator), other heat sources, and their ability to induce special regions.

Adaptations to marine versus terrestrial low temperature environments as revealed by comparative genomic analyses of the genus Psychrobacter.

While cold-adapted bacteria isolated from marine or terrestrial low temperature environments share many similarities, cold-adapted bacteria from terrestrial environments usually grow over a broader range of temperatures suggesting different constraints of these two low temperature environments. The diversity of habitats from which Psychrobacter have been isolated (e.g.