Electyrolyzer experiment designated ready-to-fly by NASA Lisa Lock Scientific Editor Andrew Zinin Chief Editor A Southwest Research Institute and University of Texas at San Antonio experiment has passed a critical NASA review, designating it ready for parabolic flight testing. The two institutions will evaluate the performance of a patent-pending electrolyzer, the Mars Atmospheric Reactor for Synthesis of Consumables (MARS-C), in partial-gravity environments. The project is led by SwRI's Kevin Supak, a program manager in SwRI's Fluids Engineering Department, and Dr.

Shrihari Sankarasubramanian, an assistant professor in UT San Antonio's Department of Biomedical and Chemical Engineering. Developed by Sankarasubramanian with NASA support, MARS-C is designed to use local resources on Mars to produce fuel, oxygen and other life-support compounds necessary for long-term human habitation. "The payload is ready to fly aboard an aircraft flying a parabolic profile.

We have demonstrated to NASA that our design, procedures and safety considerations have met the requirements needed to execute the parabolic flight test," Supak said. "This will be the first demonstration of an electrolyzer that can function in Martian ambient conditions, which have one-third of Earth's gravity, significantly colder temperatures and lower atmospheric pressure." MARS-C is an in situ resource utilization (ISRU) technology meant to improve production of propellants and life-support compounds on Mars, but similar technology can be applied to the moon and other planetary bodies. It applies voltage across two electrodes to electrochemically convert simulated Martian brine and carbon dioxide into oxygen, ethanol and other hydrocarbons.

The team adapted prototype electrochemical cells into a 3-by-7-foot payload that contains six electrochemical cells. Each cell is installed in a containment box to control ambient humidity and simulate Martian temperatures using thermoelectric heat pumps. "By qualifying for this parabolic flight, we get to learn how hydrocarbon-producing electrolyzers behave at Martian gravity conditions," Sankarasubramanian said.

"The resulting insights will help us improve system design and performance and put MARS-C on the pathway to potentially serve in astronaut life-support applications and chemical production on Mars." SwRI and UT San Antonio will test MARS-C aboard a series of parabolic flights, which will provide reduced-gravity conditions through periods of free fall created by arched flight patterns. These parabolas allow the payload to experience brief periods (about 15–20 seconds each) of lunar, Martian or zero-gravity levels. This approach builds on previous work conducted by SwRI that studied boiling processes under partial gravity aboard parabolic flights.

SwRI's research showed that lower gravity affects surface bubble dynamics, which can, in turn, affect gas production rates. "The electrolysis cells will be operated during the flight to produce ethanol and other hydrocarbons, and cameras will record the gas buildup on the electrode surfaces," Supak said. "The equipment operating the electrochemical cells will also monitor electric currents in the cells.