Plasmasphere and radiation belts
The plasmasphere and the radiation belts make up the innermost regions of the magnetosphere.
Radiation belts, energetic particles encircling the Earth
The radiation belts (also known as the van Allen belts) are toroidal regions encircling the Earth, in which very energetic (that is, very fast) particles are found. These particles are essentially trapped in the geomagnetic field. One can consider these particles to be a form of ionising radiation. As such, these particles constitute a real danger for humans and for spacecraft in orbit around the Earth.
The BIRA-IASB is very active in its study of the mechanisms by which these radiation belts are replenished during magnetic storms, as well as of the different pathways along which the particles leak away, thereby slowly emptying the belts.
Together with the CSR (Centre for Space Radiations) of the UCL, the BIRA-IASB prepares a new instrument that is able to measure this kind of radiation, the “Energetic Particle Telescope”.
The plasmasphere, a plasma cloud around the Earth
The plasmasphere is the upward extension of the Earth’s atmosphere at equatorial and mid-latitudes. It forms a plasma cloud that enshrouds the Earth.
At the BIRA-IASB, we have built a 3D-model to determine the size of the plasmasphere and its particle content.
The size of the plasmasphere changes, depending on the solar wind – magnetosphere interaction. The results of the model are compared to measurements by spacecraft, such as Cluster and IMAGE. ( )