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A lab-scale testbed for screening and characterizing the chemical specificity of commercial “off-the-shelf” (COTS) polymer adsorbents was built and tested. COTS polymer adsorbents are suitable candidates for future trace contaminant (TC) control technologies. Regenerable adsorbents could reduce overall TC control system mass and volume by minimizing the amounts of consumables to be resupplied and stored. However, the chemical specificity of these COTS adsorbents for non-methane volatile organic compounds (NMVOCs) (e.g., methanol, ethanol, dichloromethane, acetone, etc) commonly found in spacecraft is unknown. Furthermore, the effect of humidity on their filtering capacity is not well characterized. The testbed, composed of a humidifier, an incubator, and a gas generator, delivers NMVOC gas streams to conditioned sorbent tubes.

Extended habitation of space may include the cultivation of plants for atmospheric regeneration, water purification and food production. Plants produce bioactive compounds that may be released into the atmosphere as volatile organic compounds (VOCs). VOCs are produced through a variety of plant processes and vary greatly in chemistry and quantity though a plants life cycle. These compounds include numerous biogenic species including alcohols, isoprene, monoterpines, acids, carbonyls, alkanes and alkenes. In a closed environment, VOCs may create a toxic environment for either humans or other plants. Human responses to biogenic compounds may include acute toxicity, chronic toxic toxicity, and allergenic effects. Chronic exposure to low concentrations of biogenic compounds, as might be common during extended space habitation missions, is largely unstudied and of particular interest.

It is proposed to employ a greenhouse for life support on the Martian surface to reduce the equivalent system mass (ESM) penalties encountered with electrical crop lighting. The ESM of a naturally lit plant growth system compares favorably to an electrically lit system when corrections for area are made based on available light levels. A transparent structure should be more efficient at collecting insolation than collectors due to the diffusivity of the Mars atmosphere and inherent transmission losses encountered with fiber optics. The need to provide a pressurized environment for the plants indicates the use of an inflatable structure. Materials and design concepts are reviewed for their applicability to an inflatable greenhouse.

A CELSS has been defined based on current or near-term technology. The CELSS was sized to support the metabolic load of four people on the Moon for ten years. A metabolic load of 14 MJ/person/day is assumed, including an average of 2.6 hr of EVA/person/day. Close to 100% closure of water, and oxygen, and 85% closure of the food loop is assumed. With 15% of the calories supplied from Earth, this should provide adequate dietary variety for the crew along with vitamin and mineral requirements. Other supply and waste removal requirements are addressed. The basic shell used is a Space Station Freedom 7.3 m (24 ft) module. This is assumed to be buried in regolith to provide protection from radiation, meteoroids, and thermal extremes. A solar dynamic power system is assumed, with a design life of 10 years delivering power at 368 kWh/kg. Initial estimates of size are that 73 m2 of plant growth area are required, giving a plant growth volume of about 73 m3.