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How can a satellite detect a seamount that lies beneath the ocean surface?
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undersea exploration
Learn about the pioneering life and work of American oceanographer and explorer Sylvia Earle.
Satellites detect underwater features like seamounts by using a radar altimeter to measure the precise distance between the satellite and the ocean surface.1
Because a seamount has significant mass, it exerts a gravitational pull that attracts the surrounding water, causing the sea surface to bulge slightly upward directly above the feature. Conversely, deep-sea trenches cause the surface to downwarp. By mapping these subtle variations in the shape of the ocean surface, scientists can calculate the gravity field and identify the presence of uncharted seafloor topography. This method allows for comprehensive mapping of the ocean basins that would be difficult to achieve through ship-based sonar soundings alone.1