hey use a radioisotope as a source of positrons. They react the gamma particles to get a charged ion which they direct with magnetic fields for propulsion.

Rocket engines based on this would have exhaust at 10% of the speed of light.

They are initially targeting hyperefficient propulsion for cubesats and other orbital satellites.

The moderator device?—?which measures a tiny 3×3 millimeters?—?uses several layers of silicon carbide film to extract individual positrons and an electric field to cause the particles to drift to the surface of each layer, where they can cool.

* fusion reactions will be used to transfer the kinetic energy of the gamma-ray producing positron beam into charged particles.

* Positron Dynamics should be reporting on laboratory demonstration of "scalable" thrust using positrons in tests that already were tried this year.

* Positron-powered launch of small "cubesat" satellite into low-Earth orbit, demonstrating orbital change from positron propulsion. mid-2018 to mid-2019.