Patent Number: 
Section: claims

1. A spacecraft collision avoidance propulsion system for use in the presence of an ambient flux of cosmic rays, comprising:a supply of deuterium-containing particle fuel material;a store of pressurized propellant, with valves responsive to a received indication of a potential collision with a space object, for projecting the deuterium-containing particle fuel material in a specified direction outward from a spacecraft, the projected material interacting with the ambient flux of cosmic rays to generate products having kinetic energy,the spacecraft receiving at least some portion of the generated kinetic-energy-containing products to produce thrust upon the spacecraft to provide a change of trajectory of at least a dimension of the spacecraft to avoid the indicated potential collision. 2. The propulsion system as in claim 1, wherein the spacecraft is in an orbit around a planet or moon. 3. The propulsion system as in claim 1, wherein the space object is orbiting debris. 4. The propulsion system as in claim 1, wherein the space object is another spacecraft. 5. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material comprises Li6D. 6. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material comprises D2O. 7. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material comprises D2. 8. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material is in solid powder form. 9. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material is in pellet form. 10. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material is in frozen form. 11. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material is in liquid droplet form. 12. The propulsion system as in claim 1, wherein the deuterium-containing particle fuel material also contains up to 20% by weight of added non-fuel powder or dust particles. 13. A method of spacecraft propulsion for use in the presence of an ambient flux of cosmic rays for collision avoidance, comprising:projecting with pressurized propellant, through valves responsive to a received indication of a potential collision with a space object, deuterium-containing particle fuel material in a specified direction outward from a spacecraft, the projected material interacting with the ambient flux of cosmic rays to generate products having kinetic energy; andreceiving on the spacecraft at least some portion of the generated kinetic-energy-containing products to produce thrust upon the spacecraft to provide a change of trajectory of at least a dimension of the spacecraft to avoid the indicated potential collision. 14. The method as in claim 13, wherein the spacecraft is in an orbit around a planet or moon. 15. The method as in claim 13, wherein the space object is orbiting debris. 16. The method as in claim 13, wherein the space object is another spacecraft. 17. The method as in claim 13, wherein the deuterium-containing particle fuel material is Li6D. 18. The method as in claim 13, wherein the deuterium-containing particle fuel material is D2O. 19. The method as in claim 13, wherein the deuterium-containing particle fuel is D2. 20. The method as in claim 13, wherein the deuterium-containing particle fuel material is in solid powder form. 21. The method as in claim 13, wherein the deuterium-containing particle fuel material is in pellet form. 22. The method as in claim 13, wherein the deuterium-containing particle fuel material is in frozen form. 23. The method as in claim 13, wherein the deuterium-containing particle fuel material is in liquid droplet form. 24. The method as in claim 13, wherein the deuterium-containing particle fuel material also contains up to 20% by weight of added non-fuel powder or dust particles.