The spatial resolution of a satellite instrument is the smallest area on Earth that the instrument can observe. It is typically given as a distance and corresponds to the pixel size at nadir. For example, if an instrument has a spatial resolution of 50 m, and an image from that instrument is displayed at full resolution, a pixel at nadir represents an area of
50 m × 50 m on the ground. In general, spatial resolution is highest at nadir and degrades at the swath edge. In images with fine or high spatial resolution (e.g., 10 m), detailed features are discernible, such as individual buildings, roads, and trees. In images with coarse or low spatial resolution (e.g., 10 km), only large regional features are discernible, such as cities, forests, and lakes.