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NASA NTRS1994

Growth of potatoes for CELSS

This report summarizes research on the utilization of white potatoes (Solanum tuberosum L.) for space life support systems at the University of Wisconsin-Madison over the period of 1984 to 1993. At full maturity the tuber productivity was 37.5 gm(exp -2) d(exp -1), equating to a growing area requirement for one human (2800 kcal d(exp -1)) of 10.1 m(exp -2). A recirculating nutrient system using slanted trays produced best potato growth and tuber yields when a 2-3 cm layer of gravel or arcillite media was utilized. Potato production was close to maximum under lighting levels of 400 micromol m(exp -2) s(exp -1) of photosynthetic photo flux (PPF) for 24 hours or 800 micromol m(exp -2) s(exp -1) for 12 hours, alternating diurnal temperatures of 22 C and 14 C, relative humidity of 85 percent, and a carbon dioxide level of 1000 micromol m(exp -1). The range of effective concentrations of each separate nutrient is reported. The extensive studies with potatoes in this project have demonstrated that this crop has high productivity of nutritous tubers with a high harvest index in controlled environments, and can fulfill a significant portion of the energy and protein requirements for humans in space.

Tibbitts, T. W.↗

NASA NTRS1994

Methodologies for processing plant material into acceptable food on a small scale

Based on the Controlled Environment Life Support System (CELSS) production of only four crops, wheat, white potatoes, soybeans, and sweet potatoes; a crew size of twelve; a daily planting/harvesting regimen; and zero-gravity conditions, estimates were made on the quantity of food that would need to be grown to provide adequate nutrition; and the corresponding amount of biomass that would result. Projections were made of the various types of products that could be made from these crops, the unit operations that would be involved, and what menu capability these products could provide. Equipment requirements to perform these unit operations were screened to identify commercially available units capable of operating (or being modified to operate) under CELSS/zero-gravity conditions. Concept designs were developed for those equipment needs for which no suitable units were commercially available. Prototypes of selected concept designs were constructed and tested on a laboratory scale, as were selected commercially available units. This report discusses the practical considerations taken into account in the various design alternatives, some of the many product/process factors that relate to equipment development, and automation alternatives. Recommendations are made on both general and specific areas in which it was felt additional investigation would benefit CELSS missions.

Parks, Thomas R.↗

NASA NTRS1994

A study of software standards used in the avionics industry

Within the past decade, software has become an increasingly common element in computing systems. In particular, the role of software used in the aerospace industry, especially in life- or safety-critical applications, is rapidly expanding. This intensifies the need to use effective techniques for achieving and verifying the reliability of avionics software. Although certain software development processes and techniques are mandated by government regulating agencies, no one methodology has been shown to consistently produce reliable software. The knowledge base for designing reliable software simply has not reached the maturity of its hardware counterpart. In an effort to increase our understanding of software, the Langley Research Center conducted a series of experiments over 15 years with the goal of understanding why and how software fails. As part of this program, the effectiveness of current industry standards for the development of avionics is being investigated. This study involves the generation of a controlled environment to conduct scientific experiments on software processes.

Hayhurst, Kelly J.↗

NASA NTRS1994

Physiological and genetic characterization of plant growth and gravitropism in LED light sources

Among the many problems of growing plants in completely controlled environments, such as those anticipated for the space station and the CELSS program, is the need to provide light that is both adequate for photosynthesis and of proper quality for normal growth and development. NASA scientists and engineers have recently become interested in the possibility of utilizing densely packed, solid state, light emitting diodes (LED's) as a source for this light. Unlike more conventional incandescent or electrical discharge lamps, these sources are highly monochromatic and lack energy in spectral regions thought to be important for normal plant development. In addition, a recent observation by NASA scientist has suggested that infra-red LED's, that are routinely used as photographic safelights for plants grown in darkness, may interact with the ability of plants to detect gravity. In order to establish how plants respond to light from these LED light sources we carried out a series of experiments with known pigment mutants of the model mustard plant, Arabidopsis thaliana, growing in either a gravity field or on a clinostat to simulate a micro-gravity environment. Results indicate that only red light from the 665 nm LED's disrupts the ability of normal wildtype seedlings to detect a gravity stimulus. There was no consistent effect found for the far-red (735 nm) LED's or either of the infrared (880 nm or 935 nm) LED sources but both showed some effect in one or more of the genotypes tested. Of these five members of the phytochrome multigene family in Arabidopsis, only the phytochrome B pigment mutant (hy3) lacked the ability to detect gravity under all conditions. There was no effect of either micro-gravity (clinostat) or the infra-red LED's on the light induced inhibition of hypocotyl elongation. Measurements of the pigment phytochrome in oats also showed no photoconversion by 15 min irradiations with the infra-red LED's. We conclude that phytochrome B is required for the perception of gravity and that only red light is able to disrupt this perception. The infra-red LED's also do not appear to interact with gravity perception in Arabidopsis, but caution should be exercised if infra-red LED's are to be used as photographic safelights for these types of experiments.

Deitzer, Gerald F.↗

NASA NTRS1995

Automated Diagnosis Of Conditions In A Plant-Growth Chamber

Biomass Production Chamber Operations Assistant software and hardware constitute expert system that diagnoses mechanical failures in controlled-environment hydroponic plant-growth chamber and recommends corrective actions to be taken by technicians. Subjects of continuing research directed toward development of highly automated closed life-support systems aboard spacecraft to process animal (including human) and plant wastes into food and oxygen. Uses Microsoft Windows interface to give technicians intuitive, efficient access to critical data. In diagnostic mode, system prompts technician for information. When expert system has enough information, it generates recovery plan.

Clinger, Barry R.↗

NASA NTRS1994

Plant photomorphogenesis and canopy growth

An important motivation for studying photomorphogenesis is to understand the relationships among plant photophysiology in canopies, canopy productivity, and agronomic yield. This understanding is essential to optimize lighting systems used for plant farming in controlled environments (CE) and for the design of genetically engineered crop strains with altered photoresponses. This article provides an overview of some basic principles of plant photomorphogenesis in canopies and discusses their implications for (1) scaling up information on plant photophysiology from individual plants in CE to whole canopies in the field, and (2) designing lighting conditions to increase plant productivity in CE used for agronomic purposes (e.g. space farming in CE Life Support Systems). We concentrate on the visible (lambda between 400 and 700 nm) and far-infrared (FR; lambda greater than 700 nm) spectral regions, since the ultraviolet (UV; 280 to 400 nm) is covered by other authors in this volume.

Ballare, Carlos L.↗

NASA NTRS1994

Discharge lamp technologies

This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

Dakin, James↗

NASA NTRS1994

Fluorescent and high intensity discharge lamp use in chambers and greenhouses

Fluorescent and High Intensity Discharge lamps have opened up great opportunities for researchers to study plant growth under controlled environment conditions and for commercial growers to increase plant production during low/light periods. Specific technical qualities of fluorescent and HID lamps have been critically reviewed. I will direct my remarks to fluorescent and high intensity discharge (HID) lamps in growth chambers, growth rooms, and greenhouses. I will discuss the advantages and disadvantages of using each lamp in growth chambers, growth rooms and greenhouses.

Langhans, Robert W.↗

NASA NTRS1994

Adaptation of Control Center Software to Commerical Real-Time Display Applications

NASA-Marshall Space Flight Center (MSFC) is currently developing an enhanced Huntsville Operation Support Center (HOSC) system designed to support multiple spacecraft missions. The Enhanced HOSC is based upon a distributed computing architecture using graphic workstation hardware and industry standard software including POSIX, X Windows, Motif, TCP/IP, and ANSI C. Southwest Research Institute (SwRI) is currently developing a prototype of the Display Services application for this system. Display Services provides the capability to generate and operate real-time data-driven graphic displays. This prototype is a highly functional application designed to allow system end users to easily generate complex data-driven displays. The prototype is easy to use, flexible, highly functional, and portable. Although this prototype is being developed for NASA-MSFC, the general-purpose real-time display capability can be reused in similar mission and process control environments. This includes any environment depending heavily upon real-time data acquisition and display. Reuse of the prototype will be a straight-forward transition because the prototype is portable, is designed to add new display types easily, has a user interface which is separated from the application code, and is very independent of the specifics of NASA-MSFC's system. Reuse of this prototype in other environments is a excellent alternative to creation of a new custom application, or for environments with a large number of users, to purchasing a COTS package.

Collier, Mark D.↗

NASA NTRS1997

Development of an Apparatus for Wind Tunnel Dynamic Experiments at High-alpha

A unique experimental apparatus that allows a wind tunnel model two degrees of freedom has been designed and built. The apparatus was developed to investigate the use of new methods to augment aircraft control in the high angle of attack regime. The model support system provides a platform in which the roll-yaw coupling at high angles of attack can be studied in a controlled environment. Active cancellation of external effects is used to provide a system in which the dynamics are dominated by the aerodynamic loads acting on the wind tunnel model.

Pedreiro, Nelson↗

NASA NTRS1997

Development of an Apparatus for Wind Tunnel Dynamic Experiments at High-alpha

Pedreiro, Nelson↗

NASA NTRS1997

Use of Bioregenerative Technologies for Advanced Life Support: Some Considerations for BIO-Plex and Related Testbeds

A review of bioregenerative life support concepts is provided as a guide for developing ground-based testbeds for NASA's Advanced Life Support Program. Key among these concepts are the use of controlled environment plant culture for the production of food, oxygen, and clean water, and the use of bacterial bioreactors for degrading wastes and recycling nutrients. Candidate crops and specific bioreactor approaches are discussed based on experiences from the. Kennedy Space Center Advanced Life Support Breadboard Project, and a review of related literature is provided.

Wheeler, Raymond M.↗

NASA NTRS1998

Aerospace Medicine and Biology: A Continuing Bibliography

This bibliography lists reports, articles and other documents recently introduced into the NASA scientific and technical information database. Subject coverage includes: Aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life and flightcrew behavior and performance.

Source record↗

NASA NTRS1998

Protocol Development for the NASA-JSC Lunar-Mars Life Support Test Project (LMLSTP) Phase 3 Project: A Report on Baseline Studies at KSC for Continuous Salad Production

The Phase 3 Lunar-Mars Life Support Test Project (LMLSTP) was conducted in a 20-foot chamber at Johnson Space Center. The overall objective of the Phase 3 project was to conduct a 90-day regenerative life support system test involving 4 human subjects to demonstrate an integrated biological and physicochemical life support system. A secondary objective of the Phase 3 LMLSTP was to demonstrate the ability to produce salad-type vegetable by integration of a small benchtop growth chamber located within the crew habitat area. This small chamber, commercially manufactured as the Controlled Environment Research Ecosystem (CERES 2010(TM)), functioned as a means to continuously provide fresh lettuce crops for crew members. The CERES 2010(TM) growth chamber utilized hardware components developed for effective plant biomass production in spaceflight applications. These components included: (1) LED lighting; (2) Astroculture(TM) Root Trays; and (3) Zeoponic media. In planning for the LMLSTP Phase 3, a request was put forward for KSC scientists to generate a protocol for successful continuous planting, culturing, and harvesting of the salad-crop, lettuce. By conducting baseline tests with components of the CERES 2010(TM), a protocol was developed.

Goins, G. D.↗

NASA NTRS1998

Photonic and Opto-Electronic Applications of Polydiacetylene Films Photodeposited from Solution and Polydiacetylene Copolymer Networks

Polydiacetylenes (PDAS) are attractive materials for both electronic and photonic applications because of their highly conjugated electronic structures. They have been investigated for applications as both one-dimensional (linear chain) conductors and nonlinear optical (NLO) materials. One of the chief limitations to the use of PDAs has been the inability to readily process them into useful forms such as films and fibers. In our laboratory we have developed a novel process for obtaining amorphous films of a PDA derived from 2-methyl4-nitroaniline using photodeposition with Ultraviolet (UV) light from monomer solutions onto transparent substrates. Photodeposition from solution provides a simple technique for obtaining PDA films in any desired pattern with good optical quality. This technique has been used to produce PDA films that show potential for optical applications such as holographic memory storage and optical limiting, as well as third-order NLO applications such as all-optical refractive index modulation, phase modulation and switching. Additionally, copolymerization of diacetylenes with other monomers such as methacrylates provides a means to obtain materials with good processibility. Such copolymers can be spin cast to form films, or drawn by either melt or solution extrusion into fibers. These films or fibers can then be irradiated with UV to photopolymerize the diacetylene units to form a highly stable cross-linked PDA-copolymer network. If such films are electrically poled while being irradiated, they can achieve the asymmetry necessary for second-order NLO applications such as electro-optic switching. On Earth, formation of PDAs by the above mentioned techniques suffers from defects and inhomogeneities caused by convective flows that can arise during processing. By studying the formation of these materials in the reduced-convection, diffusion-controlled environment of space we hope to better understand the factors that affect their processing, and thereby, their nature and properties. Ultimately it may even be feasible to conduct space processing of PDAs for technological applications.

Paley, Mark S.↗

NASA NTRS1999

Hypogravity's Effect on the Life Cycle of Japanese Quail

A series of studies were conducted to determine the effect of activities preceding space-flight and during space-flight on quail embryonic development. While the overall development of the quail embryos was evaluated, the report presented herein, focused on calcium utilization or uptake from eggshells by developing embryos during incubation in space and on earth. In the pre-space trials, fertilized quail eggs were subjected to pre-night dynamics including forces of centrifugation, vibration, or a combination of vibration and centrifugation prior to incubation for 6 or 16 days. In another trial, fertile quail eggs were tested for survivability in a refrigerator stowage kit for eggs (RSKE) which was subsequently used to transport the eggs to space. Eggs in the RSKE were subjected to shuttle launch dynamics including G force and random vibration profiles. In the space- flight trials, 48 fertile quail eggs were launched on space shuttle Flight STS-76 and were subsequently incubated in a Slovakian incubator onboard space station, MIR. Two sets of ground controls each with 48 fertile eggs with and without exposure to launch dynamics were initiated 5 days post-launch. There was a laboratory control (incubated in Lyon RX2 incubator at 37.5 C) and a synchronous control (incubated in Lyon RX2 incubator at 39 - 400 C), which simulated the temperature of the space-flight incubator. Following space-flight trials, post-flight trials were conducted where quail eggs were incubated in Lyon RX2 or Slovakian incubators under various temperatures with or without launch dynamics. Eggshells from all study trials were retrieved and analyzed for calcium content to determine if its utilization by developing quail embryos was affected by activities preceding space-flight or during incubation in space under microgravity. Results from the pre-flight and post-flight showed that pre-flight activities and shuttle launch dynamics had no effect on calcium uptake from the eggshell by developing embryos. However, calcium uptake from the eggshell by developing embryos incubated in micro,aravity was impaired by 12.6% when compared to embryos incubated on earth under laboratory control environment. This impairment was unlikely due to factors other than microgravity. In general, calcium utilization by developing embryos increased with age of incubation with the most increase occurring at day 16 of incubation.

Hester, Patricia Y.↗

NASA NTRS1998

Recent Results from a Laboratory Study of Charging Mechanisms in a Dusty Plasma

A laboratory investigation has been developed to experimentally study the interaction of micron sized particles with plasmas and electromagnetic radiation. The intent is to investigate under what conditions particles of various compositions and sizes become charged, or discharged, while exposed to an electron beam and UV radiation. This investigation uses a unique laboratory technique known as electrodynamic suspension of particles. Here, a single charged micron size particle is suspended in a quadrupole trap and then subjected to a controlled environment. In this paper, we will discuss recent results from this experiment in which different materials including polystyrene and aluminum oxide, and sizes ranging from 10 microns to 1 micron have been used to determine charge to mass ratios and then subjected to an electron beam and /or UV radiation. In each instance, the particle's charge as well as beam current flux and radiation intensity flux is measured. These results will be compared with initial results using salt crystals. It was found that a negatively charged salt crystal exposed for 30 minutes to a 500 eV electron beam with primary electron beam current of -3.06 x 10(exp -5) picoamps yielded a secondary electron current of 3.23 x 10(exp -5) picoamps. Additionally, the particle was observed to be steadily losing charge over this time interval. By studying the microphysics of one particle, a better understanding of theoretical models and other laboratory results associated with particle charging mechanisms can be achieved.

Venturini, Catherine C.↗

NASA NTRS2000

A Dust Grain Photoemission Experiment

A laboratory experiment has been developed at Marshall Space Flight Center to study the interaction of micron-sized particles with plasmas and FUV radiation. The intent is to investigate the conditions under which particles of various compositions and sizes become charged, or discharged, while exposed to an electron beam and/or UV radiation. This experiment uses a unique laboratory where a single charged micron size particle is suspended in a quadrupole trap and then subjected to a controlled environment. Tests are performed using different materials and sizes, ranging from 10 microns to 1 micron, to determine the particle's charge while being subjected to an electron beam and /or UV radiation. The focus of this presentation will be on preliminary results from UV photoemission tests, but past results from electron beam, secondary electron emission tests will also be highlighted. A monochromator is used to spectrally resolve UV in the 120 nm to 300 nm range. This enables photoemission measurements as a function of wavelength. Electron beam tests are conducted using I to 3 micron sized aluminum oxide particles subjected to energies between 100 eV to 3 KeV. It was found that for both positive and negative particles the potential tended toward neutrality over time with possible equilibrium potentials between -0.8 Volts and 0.8 Volts.

Venturini, C. C.↗