NASA engineers have developed a system to extract oxygen from thin air-thin Martian air, that is. The device could provide breathable air and rocket-fuel oxidant for voyagers to the planet, where the atmosphere is primarily carbon dioxide. CO₂ is fed into a zirconia disk that is heated to 750 C and sandwiched between platinum electrodes. The zirconia chemically breaks the CO₂ into oxygen and carbon monoxide. The oxygen filters through the zirconia and is collected; the carbon monoxide cannot pass through the disk. NASA has demonstrated this “oxygen pump” under simulated Martian conditions at the Johnson Space Center, according to principal investigator David Kaplan. A real test will come when the device is included on the next Mars lander mission, scheduled for launch in April 2001. If it works, the system would help lower the mass and cost of future missions.