Abstract: The invention is an automatically controlled magnetic marine mine sweeping ystem that does not constitute a safety hazard to the ship deploying it. It includes a ship that trails a pair of electrodes within the water which are, in turn, electrically energized by a variable current generator to induce a magnetic field therein. The intensity of said magnetic field is sensed by a magnetometer; and by means of a closed-loop, negative-feedback circuit incorporating said magnetometer, said current generator, and said sea water, the intensity of said magnetic field is limited to the extent that it does not extend under the ship and detonate marine mines that are close enough to be destructive thereto.