Artist's impression of the European Remote-sensing Satellite (ERS-1) in orbit over the north pole. Due for launch in April 1991, ERS-1 is equipped with all-weather microwave and radar instruments which will be used primarily to study coastal, ocean and polar ice processes. The picture shows ERS-1's solar panels at top & its long Synthetic Aperture Radar antenna facing Earth. ERS-1 will play a major role in international satellite investigations into climate change, the so-called Mission to Planet Earth". It will map ocean waves, currents and tides; global sea-surface temperatures and winds; ocean floor topography and sea ice distribution."