Aerobraking and aerocapture have been shown to be mission enabling for deep space orbiters and manned missions, and yield dramatic cost and mass savings for near earth missions. However, high dynamic pressure aerocapture is high risk and requires large, complex, and heavy deflector shells. Magnetoshell Aerocapture (MAC) is a revolutionary technology that has been developed by NASA and MSNW that can enable low-cost, low-risk aerocapture for a range of Earth and deep space missions. The Magnetoshell deploys a simple dipole magnetic field containing a magnetized plasma. Interaction of neutral particles in the atmosphere with this magnetized plasma produces the desired drag for braking, acting in effect like a plasma parachute. With the aeroshell now being composed of a massless magnetic field, the scale of the shell can be as large as 100 meters with only a gram of plasma and a simple copper magnet. Drag can be dynamically controlled in response to atmospheric conditions, enabling very aggressive aerocapture maneuvers. By providing pulsed power, the thermal and power processing requirements can be kept within the scope of conventional technologies. In a Phase I NIAC program a 1.6 meter diameter Magnetoshell was demonstrated and increased the drag force of a supersonic flowing neutral jet by 1000X. A wide range of mission studies showed that MAC can enable a Neptune orbiter mission, reduce the cost of a manned Martian mission by $2B, and provide the low-cost drag system for Earth return missions. In the following proposal a three year ISS-launched CubeSat demonstration mission paves the way for full scale operation missions. In Phase I a complete system design will be completed and several of the primary technology risks will be mitigated. When demonstrated, Magnetoshell Aerocapture will dramatically reduce cost and risk for applications ranging from nanosatellites, deep space Flagship science missions, and commercial applications such as reusable tankers.