MOS (Marine Observation Satellite) were Japan's first Earth resources satellites, also known by the national name Momo ('peach blossom'). MOS-1A and -1B, launched by NASDA (National Space Development Agency), monitored ocean currents and chlorophyll levels, sea surface temperature, atmospheric water vapor, precipitation, and land vegetation, and also acted as data relays for remote surface sensor platforms. Both measured 2.4 × 1.5 meters and were launched from Tanegashima.