Simulating the outer radiation belt during space weather events (SORBS)

Start date
1 September, 2020
End date
30 April, 2024

Violent eruptions on the Sun can trigger large magnetic storms at the Earth lasting for days.  These storms can increase the number of high-energy charged particles trapped in the radiation belts and cause satellite charging, service outage and in unusual cases satellite loss.

In the SORBS project we are studying how changes in the outer boundary of the geomagnetic field lead to rapid changes in the radiation belts closer to Earth.  By studying these basic physical processes and including them into global models the project will help develop better forecasting capabilities for satellite operators.

SORBS is a collaborative project between British Antarctic Survey, the University of Cambridge and the Air Force Research Laboratory, Albuquerque, NM, USA.

The project is funded by the US Air Force Office of Scientific Research (AFOSR).  The funding is used primarily to support a PhD student based at the BAS and registered for a degree at the University of Cambridge.


Daggitt, T. A., Horne, R. B., Glauert, S. A., Del Zanna, G., & Freeman, M. P. (2022). Variations in observations of geosynchronous magnetopause and last closed drift shell crossings with magnetic local time. Space Weather, 20, e2022SW003105.

The goal of the SORBS project is to study electron acceleration and loss in the outer radiation belt and calculate the amount of satellite charging for different space weather events

To achieve this goal, we have set three objectives:

  1. To study the conditions under which electrons can be accelerated to the highest energies in the radiation belts;
  2. To determine the importance of electron losses to the outer boundary of the geomagnetic field;
  3. To calculate the amount of satellite internal charging during space weather events.

The work includes analysis of satellite and ground-based data, and running of the BAS radiation belt model (BAS-RBM) to simulate events on a global scale.

External collaborators

Dr Giulio del Zanna – Astrophysics group | Astrophysics – University of Cambridge

Dr Jay Albert – Air Force Research Laboratory