While scientists have long studied currents of large eddies, the smaller ones — called submesoscale eddies — are notoriously difficult to detect. These currents, which range from several kilometers to 100 kilometers wide, have been the ‘missing pieces’ of the ocean’s puzzle — until now. Using data from the new Surface Water and Ocean Topography (SWOT) satellite, scientists finally got a clear view of these hard-to-see currents, and they are a lot stronger than anyone thought.