An electromagnetic accelerator designed to accelerate payloads or objects without rockets. Its projected design will allow it to operate on the surface of the Moon and other celestial bodies. In weak gravity, objects could be accelerated to escape velocity. The mass driver is essentially a catapult tube comprising a magnetic object that runs along the tunnel, which is lined with electromagnets, but there is no standard design.

Potentially, it would be capable of transporting lunar material to construct a settlement on the Moon. Its design would also allow the machine to land on an asteroid heading dangerously towards the Earth; it would then break off pieces of the asteroid and hurl them into space. The idea was developed at the Massachusetts Institute of Technology.