Speaker
Description
Future human exploration missions beyond Low Earth Orbit will expose astronauts to elevated radiation risks from Galactic Cosmic Rays (GCRs) and Solar Energetic Particle (SEP) events. Conventional passive shielding becomes increasingly mass-prohibitive for long-duration missions, motivating investigation of active shielding approaches.
The ESA's AEGIS (Active Electromagnetically Generated Inductive Shield) GSTP project is assessing the feasibility of using artificially generated mini-magnetospheres as a realistic active radiation mitigation system. Unlike traditional magnetic shielding concepts that rely solely on direct particle deflection, AEGIS exploits plasma processes generated when the solar wind interacts with a local magnetic field. These interactions can produce collisionless shocks, electrostatic barriers and plasma turbulence that may enhance the scattering of energetic particles.
âImproved understanding of these underlying physical mechanisms provides a pathway towards the deliberate engineering and optimisation of plasma structures for active radiation mitigation.
A major challenge in assessing the effectiveness of such systems is the wide range of physical scales involved. Numerical modelling requires simultaneous treatment of kinetic plasma processes and the transport of energetic particles over many orders of magnitude in energy and spatial scale. Current Particle-in-Cell (PIC) simulation studies have demonstrated both the complexity of the problem and the limitations of existing computational approaches for directly modelling operational shielding scenarios.
To address these challenges, the project is developing complementary analytical models describing the interaction of energetic ions with kinetic-scale electric fields and turbulent plasma structures. These models are being used to investigate cumulative small-angle scattering processes and to establish scaling relationships relevant to radiation mitigation performance.
Experimental studies at the University of Oxford are aimed at providing laboratory measurements of collisionless plasma structures and shock-related phenomena relevant to mini-magnetosphere formation. These experiments offer an important route for validating theoretical predictions and informing future simulation efforts.
This paper presents an update on the AEGIS project, including progress in analytical modelling, numerical simulations and laboratory experiments, and discusses the implications for active radiation shielding systems for future lunar and deep-space missions. Particular attention is given to SEP energies most relevant to crew exposure during extreme solar particle events.