Satellite & Space Missions

Biography

Biography: Ruth Bamford

Abstract

Spacecraft in interplanetary space and the radiation belts are vulnerable to `cosmic rays’. Solar storms produce large numbers of energetic ions and electrons that can penetrate and disrupt solar panels, electronics and human tissue. Due to their larger mass, the energetic ions are the greater hazard as they are not easily stopped. Thick material cladding around vulnerable parts of the vessel provides diminishing effectiveness at the higher energies.

Ideas of electromagnetically deflecting the energetic charged particles fall down due to unrealistically high power requirements needed to create the size of electromagnetic field thought to be needed. Proponents over the years have focused on optimising the engineering on board the spacecraft. Until recently nobody has reexamined how the particles interact with the magnetic or electric field. It is assumed to be straightforward. However, laboratory experiments and theory have shown that this is not simple. The presence of the diffuse solar wind makes for a far more efficient shield than single particles dynamics would predict.

The question then becomes: how does this change the potential for effective active shielding for manned interplanetary spacecraft and/or satellites in the radiation belt?

What we find is for a manned mission to Mars of ~20kW of on-board power being redirected to superconducting magnetic coils system weighing approximately 3000 kg including cooling. This would reduce the energetic (> 50MeV) particle flux by about 20% during a major solar storm (assuming a severe solar storm flux of ~10¹⁰ protons/cm²sec). Additional augmentations, such as adding extra plasma into the bubble, can greatly enhance its effectiveness up to 80 to 90% exclusion overall and the extend the range of energies capable of being deflected.

Evidence that these principles will be presented from laboratory and space from the natural magnetic shielding occurring on the Moon.