Areology

Science for the Future of Mars

Survival Potential and Photosynthetic Activity of Lichens Under Mars-Like Conditions: A Laboratory Study

Survival Potential and Photosynthetic Activity of Lichens Under Mars-Like Conditions: A Laboratory Study

article featured lichen terraforming

Lichens were repetitively exposed over 22 days to thermophysical Mars-like conditions at low-and mid-latitudes. The simulated parameters and the experimental setup are described. Natural samples of the lichen Xanthoria elegans were used to investigate their ability to survive the applied Mars-like conditions. The effects of atmospheric pressure, CO2 concentration, low temperature, water availability, and light on Mars were also studied. The results of these experiments indicate that no significant decrease in the vitality of the lichen occurred after exposure to simulated martian conditions, which was demonstrated by confocal laser scanning microscopy analysis, and a 95% CO2 atmosphere with 100% humidity, low pressure (partial pressure of CO2 was 600 Pa), and low temperature has a balancing effect on photosynthetic activity as a function of temperature. This means a starting low photosynthetic activity at high CO2 concentrations with Earth-like pressure has a reduction of 60%. But, if the simulated atmospheric pressure is reduced to Mars-like conditions with the maintenance of the same Mars-like 95% CO2 concentration, the photosynthetic activity increases and again reaches similar values as those exhibited under terrestrial atmospheric pressure and concentration. Based on these results, we presume that, in any region on Mars where liquid water might be available, even for short periods of time, a eukaryotic symbiotic organism would have the ability to survive, at least over weeks, and to temporarily photosynthesize.
The resistance of the lichen Circinaria gyrosa (nom. provis.) towards simulated Mars conditions

The resistance of the lichen Circinaria gyrosa (nom. provis.) towards simulated Mars conditions

article featured lichen terraforming

The “Planetary Atmospheres and Surfaces Chamber” (PASC, at Centro de Astrobiología, INTA, Madrid) is able to simulate the atmosphere and surface temperature of most of the solar system planets. PASC is especially appropriate to study irradiation induced changes of geological, chemical, and biological samples under a wide range of controlled atmospheric and temperature conditions. Therefore, PASC is a valid method to test the resistance potential of extremophile organisms under diverse harsh conditions and thus assess the habitability of extraterrestrial environments. In the present study, we have investigated the resistance of a symbiotic organism under simulated Mars conditions, exemplified with the lichen Circinaria gyrosa—an extremophilic eukaryote. After 120 hours of exposure to simulated but representative Mars atmosphere, temperature, pressure and UV conditions; an unaltered photosynthetic performance demonstrated high resistance of the lichen photobiont.

Work content influences on cognitive task load, emotional state and performance during a simulated 520-days’ Mars mission

psychology

In high-risk domains such as human space flight, cognitive performances can be negatively affected by emotional responses to events and conditions in their working environment (e.g., isolation and health incidents). The COgnitive Performance and Error (COPE) model distinguishes effects of work content on cognitive task load and emotional state, and their effect on the professional’s performance. This paper examines the relationships between these variables for a simulated Mars-mission. Six volunteers (well-educated and -motivated men) were isolated for 520 days in a simulated spacecraft in which they had to execute a (virtual) mission to Mars. As part of this mission, every other week, several computer tasks were performed. These tasks consisted of a negotiation game, a chat-based learning activity and an entertainment game. Before and after these tasks, and after post-task questionnaires, the participants rated their emotional state consisting of arousal, valence and dominance, and their cognitive task load consisting of level of information processing, time occupied and task-set switches. Results revealed significant differences between cognitive task load and emotional state levels when work content varied. Significant regression models were also found that could explain variation in task performance. These findings contribute to the validation of the COPE model and suggest that differences in appraisals for tasks may bring about different emotional states and task performances.

Integrated Planetary Outpost Simulation to Assess Crew Psychophysiological Response

article featured habitation

One of the most effective and complex concepts in planetary settlement is the integration of interfaces such as habitat modules, rover vehicles and space suits that can connect via airlocks, suitports and tunnels, and can disconnect to operate independently. This scenario is ideal to assess common symptoms during spaceflight missions such as fatigue, sleep loss, circadian desynchronization and work overload, This paper describes the main features of an integrated system built at the Human Spaceflight Laboratory from the Department of Space Studies at the University of North Dakota and a series of feasible measurements that can be conducted there to assess psychophysiological responses of a crew during confinement. This approach may contribute in the analysis of environmental mission conditions that interfere with sleep quality and individual vulnerabilities associated to sleep loss and circadian desynchronization.

Survival Potential and Photosynthetic Activity of Lichens Under Mars-Like Conditions: A Laboratory Study

article featured lichen terraforming

Lichens were repetitively exposed over 22 days to thermophysical Mars-like conditions at low-and mid-latitudes. The simulated parameters and the experimental setup are described. Natural samples of the lichen Xanthoria elegans were used to investigate their ability to survive the applied Mars-like conditions. The effects of atmospheric pressure, CO2 concentration, low temperature, water availability, and light on Mars were also studied. The results of these experiments indicate that no significant decrease in the vitality of the lichen occurred after exposure to simulated martian conditions, which was demonstrated by confocal laser scanning microscopy analysis, and a 95% CO2 atmosphere with 100% humidity, low pressure (partial pressure of CO2 was 600 Pa), and low temperature has a balancing effect on photosynthetic activity as a function of temperature. This means a starting low photosynthetic activity at high CO2 concentrations with Earth-like pressure has a reduction of 60%. But, if the simulated atmospheric pressure is reduced to Mars-like conditions with the maintenance of the same Mars-like 95% CO2 concentration, the photosynthetic activity increases and again reaches similar values as those exhibited under terrestrial atmospheric pressure and concentration. Based on these results, we presume that, in any region on Mars where liquid water might be available, even for short periods of time, a eukaryotic symbiotic organism would have the ability to survive, at least over weeks, and to temporarily photosynthesize.

The resistance of the lichen Circinaria gyrosa (nom. provis.) towards simulated Mars conditions

article featured lichen terraforming

The “Planetary Atmospheres and Surfaces Chamber” (PASC, at Centro de Astrobiología, INTA, Madrid) is able to simulate the atmosphere and surface temperature of most of the solar system planets. PASC is especially appropriate to study irradiation induced changes of geological, chemical, and biological samples under a wide range of controlled atmospheric and temperature conditions. Therefore, PASC is a valid method to test the resistance potential of extremophile organisms under diverse harsh conditions and thus assess the habitability of extraterrestrial environments. In the present study, we have investigated the resistance of a symbiotic organism under simulated Mars conditions, exemplified with the lichen Circinaria gyrosa—an extremophilic eukaryote. After 120 hours of exposure to simulated but representative Mars atmosphere, temperature, pressure and UV conditions; an unaltered photosynthetic performance demonstrated high resistance of the lichen photobiont.