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The capabilities of the JPL Electronic Nose have been expanded to include characteristics required for a Technology Demonstration schedule on the International Space Station (ISS) in 2008-2009 [1,2]. Concurrently, to accommodate specific needs on ISS, the processes, tools and analyses which influence all aspects of development of the device have also been expanded. The Third Generation ENose developed for this program uses two types of sensor substrates, newly developed inorganic and organic sensor materials, redesigned electronics, onboard near real-time data analysis and power and data interfaces specifically for ISS. This paper will discuss the Third Generation ENose with a focus on detection of mercury in the parts-per-billion range.

The recent development of single-mode continuous wave distributed feedback mid-IR interband cascade lasers operating at thermoelectric cooler temperatures is presented. Also, latest progress of interband cascade lasers is reported.

The Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) contains an aqueous, alkaline fluid (pH 9.5±0.5) that aids in maintaining a habitable environment for the crew. Because microbes have significant potential to cause disease, adverse effects on astronaut health, and microbe-induced corrosion, the presence of both bacteria and viruses within IATCS fluids is of concern. This study sought to detect and identify viral populations in IATCS samples obtained from the Kennedy Space Center as a first step towards characterizing and understanding potential risks associated with them. Samples were concentrated and viral nucleic acids (NA) extracted providing solutions containing 8.87-22.67 μg NA per mL of heat transfer fluid. After further amplification viral DNA and cDNA were then pooled, fluorescently labeled, and hybridized onto a Combimatrix panvira 12K microarray containing probes for ∼1,000 known human viruses.

Future planetary science missions planned for Mars are expected to be more complex and thermally challenging than any of the previous missions. For future rovers, the operational parameters such as landing site latitudes, mission life, distance traversed, and rover thermal energy to be managed will be significantly higher (two to five times) than the previous missions. It is a very challenging problem to provide an effective thermal control for the future rovers using traditional passive thermal control technologies. Recent investigations at the Jet Propulsion Laboratory (JPL) have shown that mechanical pump based fluid loops provide a robust and effective thermal control system needed for these future rovers. Mechanical pump based fluid loop (MPFL) technologies are currently being developed at JPL for use on such rovers. These fluid loops are planned for use during spacecraft cruise from earth to Mars and also on the Martian surface operations.

An array-based sensing system based on 32 polymer/carbon composite conductometric sensors is under development at JPL. Until the present phase of development, the analyte set has focused on organic compounds (common solvents) and a few selected inorganic compounds, notably ammonia and hydrazine. The present phase of JPL ENose development has added two inorganics to the analyte set: mercury and sulfur dioxide. Through models of sensor-analyte response developed under this program coupled with a literature survey, approaches to including these analytes in the ENose target set have been determined.

The development of mid-IR semiconductor diode lasers based on type-II interband cascade structures is presented. How these diode lasers can be developed to meet the requirements in chemical sensing applications is discussed.

A technology demonstration propylene Loop Heat Pipe (LHP) has been tested extensively in support of the implementation of this two-phase thermal control technology on NASA’s Earth Observing System (EOS) Tropospheric Emission Spectrometer (TES) instrument. This cryogenic instrument is being developed at the Jet Propulsion Laboratory (JPL) for NASA. This paper reports on the transient characterization testing results showing low frequency temperature oscillations. Steady state performance and model correlation results can be found elsewhere. Results for transient startup and shutdown are also reported elsewhere. In space applications, when LHPs are used for thermal control, the power dissipation components are typically of large mass and may operate over a wide range of power dissipations; there is a concern that the LHP evaporator may see temperature oscillations at low powers and over some temperature range.

The Trace Gas Analyzer (TGA, Figure 1) is a self-contained, battery-powered mass spectrometer that is designed for use by astronauts during extravehicular activities (EVA) on the International Space Station (ISS). The TGA contains a miniature quadrupole mass spectrometer array (QMSA) that determines the partial pressures of ammonia, hydrazines, nitrogen, and oxygen. The QMSA ionizes the ambient gas mixture and analyzes the component species according to their charge-to-mass ratio. The QMSA and its electronics were designed, developed, and tested by the Jet Propulsion Laboratory (1,2). Oceaneering Space Systems supported JPL in QMSA detector development by performing 3D computer for optimal volumetric integration, and by performing stress and thermal analyses to parameterize environmental performance.

As a result of the Viking missions in 1970s, the presence of a strong oxidant in Martian soil was suggested. Here we present a testable, by near-term missions, hypothesis that iron(VI) contributes to that oxidizing pool. Ferrate(VI) salts were studied for their spectral and oxidative properties and biological activities. Ferrate(VI) has distinctive spectroscopic features making it available for detection by remote sensing reflectance spectra and contact measurements via Mössbauer spectroscopy. The relevant miniaturized instrumentation has been developed or is underway, while XANES spectroscopy is shown to be a method of choice for the returned samples. Ferrate(VI) is capable of splitting water to yield oxygen, and oxidizing organic carbon to CO2. Organic oxidation was strongly abated after pre-heating ferrate, similar to the observations with Mars soil samples.

In October, 1998, the first of the NASA New Millennium Spacecraft, DS1, was successfully launched into space. The objectives for this spacecraft are to test advanced technologies that can reduce the cost or risk of future missions. One of these technologies is the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET). Although part of the advanced technology validation study, the array is also the spacecraft power source. Funded by BMDO, the SCARLET™ concentrator solar array is the first spaceflight application of a refractive lens concentrator. As part of the DS1 validation process, the amount of array diagnostics is very extensive. The data obtained includes temperature measurements at numerous locations on the 2-wing solar array. For each individual panel, a 5-cell module in one of the circuit strings is wired so that a complete I-V curve can be obtained. This data is used to verify sun pointing accuracy and array output performance.

The power produced by an AMTEC is dependent on the porosity of the electrode layers deposited on the surface of the BASE tubes. The elevated temperatures at which these power generators operate result in a slow growth or coalescence of the grains that comprise the electrode layers thereby reducing porosity and effective surface area. The lifetime of AMTEC electrodes is therefore related to the rate of grain growth of the electrode material. A preliminary model has been developed to determine the rate of grain growth over the operational lifetime of an AMTEC. This model examines the conditions for continuous growth as a function of the relative sizes, boundary and activation energies and mobilities of the grains. An assumption of strain-free growth has been made in determining the factors for normal growth. Experimental measurements for titanium nitride alloy electrodes are compared with this model. Predictions are made for performance lifetimes out to 10 years.