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PubMedDate not supplied

Terraforming: making an Earth of Mars.

As we understand more about life on Earth and about the chemical and biological potential of other planets and objects in our solar system, it's not too much of a leap to consider creating a habitable environment on another planet. Scientists have begun to ponder the possibility of transforming Mars, the most Earthlike of the nearby planets. Various scenarios have been proposed, and in many ways these scenarios duplicate the processes that transformed the early Earth. Here we look at some of the possibilities.

Atmosphere↗
PubMed1995

Life as a planetary phenomenon: the colonization of Mars.

Life is a planet-wide phenomenon in which its components incessantly move and interact. Life imperatively recycles its parts at the surface of the Earth in a chemical transformation and physical transport that depends utterly on the energy from a recent star, the Sun. Humanity, entirely dependent on other beings, plays a recent and relatively small part in the great phenomenon of life that transports and transforms the surface of the Earth. Our species accelerates but does not dominate the metabolism of the Earth system. Ironically, during the Apollo days of the sixties, fears were rampant that Martian or other extraterrestrial "germs" might "contaminate" our planet. After Viking, such fears are seen as the manifestation of cultural paranoia. The Viking missions complemented ground-based astronomical observation and yielded definitive evidence for the lack of life on the red planet. The Gaia hypothesis states that the surface temperature, composition of the reactive gases, oxidation state, alkalinity-acidity on today's Earth are kept homeorrhetically at values set by the sum of the activities of the current biota. Life, in other words, not only produces and maintains its immediate environment, but appears on Earth only as a planetary phenomenon. Since the natural tendency of all life is to grow exponentially to fill proximal volume, the question now "can life ecopoietically expand to Mars?" is entirely equivalent to the query of "can Gaia reproduce?"

Earth, Planet↗
PubMed1997

The limits of life on Earth and searching for life on Mars.

Considerations of basic properties of bacteria such as size, structure, and metabolic versatility allow one to understand how these remarkable life-forms are so adaptable to environments previously thought to be uninhabitable. It is now appreciated that bacteria on Earth can utilize almost any redox couple that yields energy, taking advantage of this energy, while transforming the elements during metabolism. The ability to grow at the expense of inorganic redox couples allows the microbes to occupy niches not available to the more metabolically constrained eukaryotes. Furthermore, the simplicity of the bacterial structure allows them considerably more resistance to environmental variables (pH, salinity, temperature) that are toxic or lethal to more complex organisms. This information can be used to explain the predominance of prokaryotes in extreme environments on Earth, and to speculate as to simple types of metabolism and biogeochemical cycles that may exist on this planet, Mars, and perhaps other non-Earth environments.

Adenosine Triphosphate↗
PubMed1997

Lessons learned studying design issues for lunar and Mars settlements.

In a study of lunar and Mars settlement concepts, an analysis was made of fundamental design assumptions in five technical areas against a model list of occupational and environmental health concerns. The technical areas included the proposed science projects to be supported, habitat and construction issues, closed ecosystem issues, the "MMM" issues (mining, material processing, and manufacturing), and the human elements of physiology, behavior, and mission approach. Four major lessons were learned. First it is possible to relate public health concerns to complex technological development in a proactive design mode, which has the potential for long-term cost savings. Second, it became very apparent that prior to committing any nation or international group to spending the billions to start and complete a lunar settlement, over the next century, that a significantly different approach must be taken from those previously proposed, to solve the closed ecosystem and "MMM" problems. Third, it also appears that the health concerns and technology issues to be addressed for human exploration into space are fundamentally those to be solved for human habitation of the Earth (as a closed ecosystem) in the 21st century. Finally, it is proposed that ecosystem design modeling must develop new tools, based on probabilistic models as a step up from closed circuit models.

Aerospace Medicine↗
PubMedDate not supplied

The cave that holds clues to life on Mars.

Deep in Lechuguilla Cave, a researcher ponders slots carved millions of years ago by dripping sulfuric acid. Though the cave was formed by acid bubbling up from below, here gases condensed on the chamber's ceiling and then rained down as acid. Scientists think Mars may also hold caves carved by sulfuric acid. On Earth, almost all other caves are formed by flowing water.

Antibiotics, Antineoplastic↗
PubMed2001

Radiation protection using Martian surface materials in human exploration of Mars.

To develop materials for shielding astronauts from the hazards of GCR, natural Martian surface materials are considered for their potential as radiation shielding for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley's HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To develop structural shielding composite materials for Martian surface habitats, theoretical predictions of the shielding properties of Martian regolith/polyimide composites has been computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance structural properties also enhances the shielding properties of these composites because of the added hydrogenous constituents. Heavy ion beam testing of regolith simulant/polyimide composites is planned to validate this prediction. Characterization and proton beam tests are performed to measure structural properties and to compare the shielding effects on microelectronic devices, respectively.

Cosmic Radiation↗
PubMed1998

Operational psychology countermeasures during the Lunar-Mars Life Support Test Project.

The Crew and Thermal Systems Division at the NASA Johnson Space Center conducted a series of human-rated tests, termed the Lunar-Mars Life Support Test Project (LMLSTP), designed to advance technology in closed life support systems. As the duration of these tests lengthened, the psychological factors associated with placing humans in these environments became increasingly salient to successful mission completion. A number of psychological activities were conducted to ensure successful operations and protect crew member well-being, including individual crew member selection, crew composition, training and preparation, family inclusion, educational briefings, in-mission tracking, operational interventions, and postmission repatriation. This article describes these activities, the rationale behind their design, the similarities and differences to techniques utilized for spaceflight, and considerations related to designing psychological countermeasures for confined environments. In addition to testing physical and engineering systems, the LMLSTP series functioned as an effective testbed for developing operational concepts and countermeasures for extended space missions.

Adaptation, Psychological↗
PubMed1972

Biological instrumentation for the Viking 1975 mission to Mars.

A brief introduction is given on why Mars is of interest from a biological point of view, along with an overview of the Viking 1975 mission. Details are given about the four biology instruments aboard the spacecraft and the experiments for which they are to be used. These are: the carbon assimilation experiment to determine whether the soil is biologically active, by incubation in presence of 14C-labelled CO and CO2 (known to be present in the Martian atmosphere); the label release experiment to detect metabolic activity by the release of radioactive CO2, from 14C-labelled simple organic substrates; the gas exchange experiment to detect biological activity by repeated gas chromatography analysis of soil samples; the light scattering experiment, where increase of scattering and decrease of light transmission would indicate the growth of organisms. Examples are given of data obtained with terrestrial soils in these experiments.

Biology↗
PubMed2002

Mars inflatable greenhouse analog.

Light intensities on the Martian surface can possibly support a bioregenerative life support system (BLSS) utilizing natural sunlight for hydroponic crop production, if a suitable controlled environment can be provided. Inflatable clear membrane structures offer low mass, are more easily transported than a rigid structure, and are good candidates for providing a suitable controlled environment for crop production. Cable culture is one hydroponic growing system that can take advantage of the beneficial attributes of the inflatable structure. An analog of a Mars inflatable greenhouse can provide researchers data on issues such as crew time requirements for operation, productivity for BLSS, human factors, and much more at a reasonable cost. This is a description of one such design.

Ecological Systems, Closed↗
PubMed2002

People challenges in biospheric systems for long-term habitation in remote areas, space stations, moon, and Mars expeditions.

People who participate in remote and difficult expeditions, such as the 2-year (1991-1993) Biosphere 2 experiment or a future biospheric system on Mars or other long voyages, will face individual psycho-physiological, social, and cultural value challenges. The individual psycho-physiological vectors include the lure of being a hero/heroine and pushing it to the maximum, concealment of problems with the belief that he/she can overcome the obstacle alone, as well as the difficulty of keeping intact the critical differentiation of the risks associated with the overall expedition as opposed to the experimental objectives. The social challenges occur as a group dynamic context as well as for the individual, resulting in regressions and the need to "act out" one's difficulties. Cultural areas of importance that must be taken into consideration will include esthetic, ethical, cosmological, and epistemological values. The epistemological values must involve the five methods of scientific inquiry for a comprehensive total systems project to succeed fully.

Adaptation, Psychological↗
PubMed2002

Human factor observations of the Biosphere 2, 1991-1993, closed life support human experiment and its application to a long-term manned mission to Mars.

Human factors are a key component to the success of long-term space missions such as those necessitated by the human exploration of Mars and the development of bioregenerative and eventually self-sufficient life support systems for permanent space outposts. Observations by participants living inside the 1991-1993 Biosphere 2 closed system experiment provide the following insights. (1) Crew members should be involved in the design and construction of their life support systems to gain maximum knowledge about the systems. (2) Individuals living in closed life support systems should expect a process of physiological and psychological adaptation to their new environment. (3) Far from simply being a workplace, the participants in such extended missions will discover the importance of creating a cohesive and satisfying life style. (4) The crew will be dependent on the use of varied crops to create satisfying cuisine, a social life with sufficient outlets of expression such as art and music, and to have down-time from purely task-driven work. (5) The success of the Biosphere 2 first 2-year mission suggests that crews with high cultural diversity, high commitment to task, and work democracy principles for individual responsibility may increase the probability of both mission success and personal satisfaction. (6) Remaining challenges are many, including the need for far more comprehensive real-time modeling and information systems (a "cybersphere") operating to provide real-time data necessary for decision-making in a complex life support system. (7) And, the aim will be to create a noosphere, or sphere of intelligence, where the people and their living systems are in sustainable balance.

Adaptation, Psychological↗
PubMed2002

Airtight sealing a Mars base.

Atmospheric leakage from a Mars base would create a demand for continuous or periodic replenishment, which would in turn require extraction or mining for oxygen and other gases from local resources and attendant equipment and energy requirements for such operations. It therefore becomes a high priority to minimize leakage. This article quantifies leak rates as determined by the size of holes and discusses the implications of pressure for structural configuration. The author engineered the sealing of Biosphere 2 from which comparisons are drawn.

Air Conditioning↗
PubMed2002

[Certain principles of Mars mission crew life and the organization of the performance].

Article is devoted to some new aspects of biomedical support and countermeasures during a manned Mars mission. Significant differences in crew--Mission control interaction in a Martian and orbital flight are described. Special attention is paid to the problem of the Martian crew autonomy and decision-making. The authors give some practical recommendations for improvement of the space flight medical support system existing in Russia to meet the needs of a Martian expedition.

Astronauts↗
PubMed2003

Can CO2 help harvest minerals on Mars?

When astronauts first go to Mars, it will be difficult for them to bring everything they need to survive. Even the first tentative explorations could last as long as two years. However, spaceships can carry only limited supplies. "We might have to do what explorers have done for ages: live off the land," says chemical engineer Ken Debelak of Vanderbilt University. It is a meager atmosphere, compared to Earth's, and it is about 95% carbon dioxide. This, however, turns out to be an advantage. The CO2, says Debelak, can be used to harvest almost everything else.

Carbon Dioxide↗
PubMed2003

[A mission to Mars: the prognostic analysis of concurrent psychological problems].

Psychological implications of situations that may take place during a mission to Mars including desynchronosis, fatigue, psychic asthenization, acute mental disorders, interruption of the information flow, unpredicted transformation of the socio-psychological needs, a persistent conflict tension in the crew, errors in manual control of the vehicle, refusal or impossibility to fulfill an operation, difficulties in communication between the crew and ground controllers were analyzed for determination of their causes and consequences, probable starting time, ways and methods of preventing and surmounting each of these situations.

Astronauts↗
PubMedDate not supplied

[Evaluation of the radiation risk of determinate effects from space radiation in a piloted mission to Mars].

Solar cosmic rays (SCR) are one of the sources of radiation risk specific to space flights. On Earth, occupational exposure has a regular character and radiation risk is an attribute of nothing else but stochasticity of radiobiological effects. In space flight, SCR impart stochasticity to the radiation environment and, therefore, probability to all, including determinate, radiobiological effects. The most dangerous effect is radiation disease the dosimetric functional of which is an equivalent dose to the blood-forming organs. In addition, this radiation pathology is modulated by reparative processes in the blood-forming tissue which must be also taken into account during radiation risk evaluation. Using the speculated mission to Mars as an example, it was shown that radiation risk of determinate effects defined as probability of death by radiation disease in consequence of exposure to SCR can be comparable in value to the risk from stochastic effects.

Cosmic Radiation↗
PubMedDate not supplied

[Assessment and prediction of health status of the Mars mission crew members].

The scientific concept of health assessment and prediction in a piloted mission to Mars has been built on the principles of pre-nosologic diagnostics, i.e., identification of the norm-pathology borderline states. The article deals with the medical care policy for the mission, and specific techniques and technologies. A three-level system of health assessment and prediction is proposed. Innovative approaches to evaluation of the body control systems during long exposure in microgravity have a footing of ground-based and space experimental investigations. Namely, these include evaluation of the cardiorespiration autonomous regulation and body functional reserve assessment by noninvasive recording of physiological signals in sleeping crewmembers before and after mission.

Adaptation, Physiological↗