About the project
Plasma is continuously ejected into interplanetary space by the sun, forming the ‘solar wind’. The solar wind is a highly dynamic environment, driven by activity on the Sun’s surface and in the corona. Explosive releases of plasma from the Sun called coronal mass ejections (CMEs) expand into interplanetary space at supersonic speeds, generating a shockwave at their boundaries with the rest of the solar wind. Shockwaves in space are ‘collisionless’ – the energy in the flow cannot be dissipated by particle collisions (viscosity) since the density is far too low. Instead, electromagnetic effects at the smallest plasma scales must be responsible. At the boundaries of Earth’s magnetosphere, we have observed that ‘magnetic reconnection’ can contribute to this transfer of energy in the shock layer. Magnetic reconnection is a localised change in the magnetic topology which releases energy from the fields to the particles, leading to heating and particle acceleration. With the launch of NASA’s Parker Solar Probe and ESA’s Solar Orbiter spacecraft, we have a new and growing database of observations of interplanetary shockwaves as they propagate through the inner heliosphere.
The aim of this project is to identify whether (and where) structures associated with magnetic reconnection can be found within interplanetary CMEs, and quantify their impact on the energetics of the shock (including cosmic ray acceleration). This will be achieved using a combination of spacecraft observations and high-performance simulations.
The student will:
- adapt methods for identification and classification of kinetic-scale shock structures to spacecraft in the inner heliosphere
- perform a survey of interplanetary shock waves driven by coronal mass ejections and other interplanetary shocks observed by Parker Solar Probe and Solar Orbiter
- directly compare the observed structures and statistical trends to those seen at Earth and in high performance plasma simulations run by the student in Southampton.
We expect these outcomes to aid in preparation for future science with missions such as NASA’s Helioswarm, and proposed missions such as Plasma Observatory and MAKOS.