sentences:  GCOM-C was launched on December 23, 2017 via a H-IIA rocket.AMSR2 (Advanced Microwave Scanning Radiometer 2) is an improved version of AMSR (aperture 2.0 m) on ADEOS II and AMSR-E (aperture 1.6 m) on NASA's Aqua satellite.By rotating a disc antenna (diameter 2.0 m) in 1.5 s period, it scans the Earth surface along an arc of 1450 km length.