Гусев Анатолий Александрович   (ИКИ РАН)

Antiprotons Stored in the Planetary Magnetospheres as a Fuel for Future Space Missions

We show that the Earth and other planets having the magnetospheres possess the antiproton radiation belts created due to the galactic cosmic ray nuclear interactions with the residual atmosphere. The Earth magnetosphere contains even two antiproton radiation belts: inner and outer, the last one is originated by albedo antineutron decay. We estimated the total antiparticle mass contained within the Earth magnetospheres and find magnetically confined and accumulated fluxes significantly exceed the fluxes observable in interplanetary space by up to two orders of magnitude at some energies. Based on preliminary calculations, antiproton planetary content is Earth  g (inner belt)  g (outer belt) Jupiter  g Saturn  g Uranus  g Neptune  g. It is anticipated that stored antiparticle energy can be adapted for use as a fuel for propelling spacecraft to high velocities for remote solar system missions. Our estimations show that for practical space exploration it is necessary 10 mgrams antimatter for 100 ton 1 year round trip mission to Jupiter; 30 nanograms for 45 day flight to Mars. Draper Laboratory and its collaborators (J.Bickford, W. Spjeldvik et al) proposed to use a magnetic scoop to extract large quantities of these trapped antiparticles. Preliminary thruster experiments already underway in Draper Laboratory.