[en] The feasibility of the design, construction, launch and retrieval of a hinged 15 ft by 110 ft platform, containing an array of interleaved CR-39 and Lexan track-recording detectors to be placed into circular orbit by space shuttle, is assessed. The total weight of the detector assembly plus supporting structure and accessories is 32,000 pounds. The modular construction permits as little as one fourth of the payload to be exposed at one time. The CR-39 detector has sensitivity adequate to detect and study cosmic rays ranging from minimum ionizing iron-group nuclei to the heaviest elements. The detectors will survive a one year exposure to trapped protons without losing their high resolution. Advantages include low cost, huge collecting power (approximately 150 sq m) as well as the high resolution previously attainable only with electronic detectors