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Averner, Maurice M.

Publications and source records attributed to Averner, Maurice M..

Use of Spacecraft Data to Drive Regions on Mars where Liquid Water would be Stable

Combining Viking pressure and temperature data with Mars Orbital Laser Altimeter (MOLA) topography data we have computed the fraction of the martian year during which pressure and temperature allow for liquid water to be stable on the martian surface. We find that liquid water would be stable within the Hellas and Argyre basin and over the northern lowlands equatorward of about 40 degrees. The location with the maximum period of stable conditions for liquid water is in the southeastern portion of Utopia Planitia where 34% of the year liquid water would be stable if it was present. Locations of stability appear to correlate with the distribution of valley networks.

Lobitz, Brad

The NASA CELSS program

The NASA Controlled Ecological Life Support System (CELSS) program was initiated with the premise that NASA's goal would eventually include extended duration missions with sizable crews requiring capabilities beyond the ability of conventional life support technology. Currently, as mission duration and crew size increase, the mass and volume required for consumable life support supplies also increase linearly. Under these circumstances the logistics arrangements and associated costs for life support resupply will adversely affect the ability of NASA to conduct long duration missions. A solution to the problem is to develop technology for the recycling of life support supplies from wastes. The CELSS concept is based upon the integration of biological and physico-chemical processes to construct a system which will produce food, potable water, and a breathable atmosphere from metabolic and other wastes, in a stable and reliable manner. A central feature of a CELSS is the use of green plant photosynthesis to produce food, with the resulting production of oxygen and potable water, and the removal of carbon dioxide.

Averner, Maurice M.

Controlled Ecological Life Support System

The NASA CELLS program is based upon the integration of biological and physiochemical processes in order to produce a system that will produce food, a breathable atmosphere, and potable water from metabolic and other wastes. The CELSS concept is described and a schematic system diagram is provided. Central to the CELSS concept is the Plant Growth Chamber, where green plant photosynthesis produces food, and aids in the production of oxygen and water. Progress to date at the Breadboard Facility at the Kennedy Space Center is summarized. The Breadboard Facility will implement the basic techniques and processes required for a CELSS based on photosynthetic plant growth in a ground-based system of practical size and results will be extrapolated to predict the performance of a full-sized system. Current available technology and near-future forecasts for plant growth techniques (focusing on maximum productivity), food sources (to select optimal CELSS plants), and waste management and contaminant control are discussed.

Averner, Maurice M.

Operation of an experimental algal gas exchanger for use in a CELSS

Concepts of a Closed Ecological Life Support System (CELSS) anticipate the use of photosynthetic organisms (higher plants and algae) for air revitalization. The rates of production and uptake of carbon dioxide and oxygen between the crew and the photosynthetic organisms are mismatched. An algal system used for gas exchange only will have the difficulty of an accumulation or depletion of these gases beyond physiologically tolerable limits (in a closed system the mismatch between assimilatory quotient (AQ) and respiratory quotient (RQ) is balanced by the operation of the waste processor). The results are given of a study designed to test the feasibility of using environmental manipulations to maintain physiologically appropriate atmospheres for algae and mice in a gas closed system. Specifically, the atmosphere behavior of this system is considered with algae grown on nitrate or urea and at different light intensities and optical densities. Manipulation of both allow operation of the system in a gas stable manner. Operation of such a system in a CELSS may be useful for reduction of buffer sizes, as a backup system for higher plant air revitalization and to supply extra oxygen to the waste processor or during crew changes.

Smernoff, David T.

Operation of an experimental algal gas exchanger for use in a CELSS

Concepts of a CELSS anticipate the use of photosynthetic organisms for air revitalization. The rates of production and uptake of carbon dioxide and oxygen between the crew and the photosynthetic organisms are mismatched. An algal system used for gas exchange only will have the difficulty of an accumulation or depletion of these gases beyond physiologically tolerable limits. The results of a study designed to test the feasibility of using environmental manipulations to maintain physiologically appropriate atmospheres for algae (Chlorella pyrenoidosa) and mice (Mus musculus strain DW/J) in a gas-closed system is reported. Specifically, the atmosphere behavior of this system with Chlorella grown on nitrate or urea and at different light intensities and optical densities is considered. Manipulation of both the photosynthetic rate and the assimilatory quotient of the alga has been found to reduce the mismatch of gas requirements and allow operation of the system in a gas-stable manner.

Smernoff, David T.