Sentinel-3A, the European Space Agency (ESA) – developed Earth observing satellite successfully launched on February 16, 2016. Sentinel-3A is part of Europe’s Copernicus environment program and carries four sensors: The Sea and Land Surface Temperature Radiometer (SLSTR), the Ocean Land Colour Instrument (OLCI), the Synthetic Aperture Radar (SAR) Altimeter, and the microwave radiometer.
Researchers who use Terra MODIS data are particularly interested in OLCI. OLCI images the earth similarly to MODIS on NASA’s Terra and Aqua satellites. It measures specific ocean color, vegetation and atmospheric measurements at 300m spatial resolution and at 1270 km swath width. Sentinel 3A has a morning crossing time like Terra, making Sentinel-3A the most similar to Terra satellite currently flying. Like MODIS data, Sentinel data will be free of charge and provided worldwide.