2002 · Japan Aerospace Exploration Agency
USERS (Unmanned Space Experiment Recovery System) was a Japanese microgravity experimental satellite. After 8.5 months in orbit, a reentry vehicle was to be returned to earth with the materials manufacturered in space. DRTS (Data Relay & Tracking Satellite) is an inter-satellite communications experiment satellite to relay data between the target spacecraft (low earth orbit satellites, space stations, etc.) and ground stations.