The MIDAS 4 (MIssile Defense Alarm System) satellite was designed primarily to detect the exhaust heat from a recently launched ICBM by use of infrared sensors. Secondary objectives included the measurement of cosmic radiation and the ejection of 350 million copper needles into orbit around the earth (Project West Ford). The needles were to serve as an artificial scattering medium for radio signals in the centimeter band. The spacecraft was cylindrical in shape and measured approximately 6 m in length and 1.5 m in diameter. The IR sensors and communication subsystem were chemical battery powered. Once in orbit, the spacecraft was stabilized in a nose-down attitude so that the IR sensors and telemetry antenna were always facing earthward. The satellite was successfully launched into a near polar orbit on October 21, 1961; however, the needles failed to release.