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A reliable nutrient delivery system is essential for long-term cultivation of plants in space. At the Kennedy Space Center, a series of ground-based tests are being conducted to compare candidate plant nutrient delivery systems for space. To date, our major focus has concentrated on the Porous Tube Plant Nutrient Delivery System, the ASTROCULTURE™ System, and a zeoponic plant growth substrate. The merits of each system are based upon the performance of wheat supported over complete growth cycles. To varying degrees, each system supported wheat biomass production and showed distinct patterns for plant nutrient uptake and water use.

This project sought to develop a photocatalytic oxidation (PCO) based total organic carbon (TOC) analyzer for real time monitoring of air quality in spacecraft. Specific requirements for this application were to convert volatile organic contaminants (VOC) into CO2 stoichiometrically in a single pass through a small reactor with low power requirement. One of the greatest challenges of this TiO2-mediated PCO was the incomplete oxidation of some recalcitrant VOCs leading to less reactive intermediates that deactivate the catalyst over time. Dichloromethane (DCM) is one of these VOCs. The effect of some design factors (e.g. TiO2 catalyst surface area to volume ratio and UV photon flux field) as well as operating conditions of an annular reactor (e.g. VOC residence time and relative humidity) on the efficiency in converting DCM to CO2 were investigated.

Light-emitting diodes (LEDs) represent an innovative artificial lighting source with several appealing features specific for supporting plants, whether on space-based transit vehicles or planetary life support systems. Appropriate combinations of red and blue LEDs have great potential for use as a light source to drive photosynthesis due to the ability to tailor irradiance output near the peak absorption regions of chlorophyll. This paper describes the importance of far-red radiation and blue light associated with narrow-spectrum LED light emission. In instances where plants were grown under lighting sources in which the ratio of blue light (400–500 nm) relative to far-red light (700–800 nm) was low, there was a distinct leaf stretching or broadening response. This photomorphogenic response sanctioned those canopies as a whole to reach earlier critical leaf area indexes (LAI) as opposed to plants grown under lighting regimes with higher blue:far-red ratios.

Growth Temperatures And Lighting Intensity Are Key Factors That Directly Impact The Design, Engineering, And Horticultural Practices Of Sustainable Life-Support Systems For Future Long-Term Space Missions. The Effects Of Exposure Of Lettuce (Cv. Flandria), Radish (Cv. Cherry Bomb Ii). And Green Onion (Cv. Kinka) Plants To Controlled Environment Temperatures (Constant Day/Night Temperature Of 22, 25, Or 28 °C) And Lighting Intensities (8.6, 17.2, Or 25.8 Mol M−2 D−1 Photosynthetic Photon Flux [Ppf]) At Elevated Co2 (1200 µMol Mol−1) Was Investigated To Ascertain Overall Yield Responses. Following 35 Days Growth, The Yields Of Lettuce Indicated That Increasing The Growing Temperature From 22 To 28°C Slightly Increased The Edible Fresh Mass Of Individual Plants. However, Even Though Lettuce Plants Grown Under High Ppf Had The Highest Fresh Mass, The Resultant Increase In The Incidence And Severity Of Tipburn Reduced The Overall Quality Of The Lettuce Head.