Sailing to the Ends of the EarthSail Thor The Vessel Thor is a 65 foot cutter rigged aluminum go-anywhere vessel, built to ice-going standards, able to be handled by a small crew. With her shallow draft and hydraulic retractable keel, she can maneuver in the shallowest waters. Learn More Team Thor Gerd Marggraff: Skipper40 years of engineering experience. German Offshore Yacht Master. Australian Commercial Captain’s License and Marine Engineer Driver License. Lifetime of sailing including over 100,000 sea miles. Melissa MarggraffPhysicist. Lifetime of sailing including over 50,000 sea miles.