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The Plant Research Unit (PRU) is currently under development by the Space Station Biological Research Project (SSBRP) team at NASA Ames Research Center (ARC) with a scheduled launch in 2001. The goal of the project is to provide a controlled environment that can support seed-to-seed and other plant experiments for up to 90 days. This paper describes testing conducted on the major PRU prototype subsystems. Preliminary test results indicate that the prototype subsystem hardware can meet most of the SSBRP science requirements within the Space Station mass, volume, power and heat rejection constraints.

This paper describes the development of a lead free, high temperature ceramic capacitor material having the base composition of (Na0.5 Bi0.5) TiO3. The goal is to modify this structure to create a material that has the relative permittivity of barium titanate with extended X7R-like properties to 250°C - an X14R. After an extensive compositional and theoretical modeling investigation a composition was selected and capacitors developed. The dielectric has a 1-kHz relative permittivity of ∼1200 with <±15% variation from -25 to +250°C and <5% loss from -55 to +250°C. These capacitors also have very low voltage coefficients, indeed they are positive at the low end of the temperature range, resulting in a combined TC-Vc capacitance variation 0%/-25% of nominal from -55 to +200°C with applied voltage stress from 20 to 260 V/mil.

The Carbon Dioxide Removal Assembly (CDRA) on board the International Space Station (ISS) has experienced periodic check valve and selector valve failures as a result of a gradual build-up of contamination from particles that have breeched the adsorbent bed seals. The current software that controls CDRA has limitations that make troubleshooting the unit difficult in these situations, in large part due to the fact that valve position telemetry is only available during certain times. There are also situations where it is required to perform operations manually that would benefit from added code logic and commands to facilitate these operations. The software has been reviewed for possible upgrades and changes that will allow engineers to better troubleshoot the unit in the event of various failures and also allow for better operability in degraded states.

Total sample containment is an absolute requirement for Mars sample return missions, derived from the requirement to protect against uncontrolled introduction of potentially hazardous foreign material into the earth's biosphere. These constraints of planetary protection comprise one of the major remaining hurdles to low cost implementation of sample return missions. It is suggested here that to spread the costs of the program, the first mission should consider sterilizing the samples and canister surfaces while still in space during the return to Earth.

The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.