Searching for substorm onset using Earth's aurora

One of the biggest unknowns in near-Earth space is termed the Magnetospheric substorm, a sudden and rapid reconfiguration of Earth's magnetosphere leading to a substantial amount of energy transfer into the ionosphere and the creation of dynamic auroral displays in the Northern and Southern hemispheres. The major open question is what physical processes trigger substorms, generally thought to be a plasma instability in the magnetotail driven unstable via energy accumulation in the stretched magnetic fields and energised plasma. However, the substorm is thought to be initiated in a very small volume of 3D space, and our measurements are sparse.

High-resolution auroral observations of the evolution of the substorm onset arc are key to understanding this onset instability. "Auroral beads", a travelling wave phenomenon along the substorm onset arc, are thought to be a projection of the magnetotail instability into the ionosphere, allowing the instability characteristics to be remotely sensed by using the ionosphere as a TV screen.

As part of a large, national consortium, Northumbria University have recently purchased 4 state-of-the-art auroral cameras due to deploy in Scandinavia in 2023. These auroral cameras will be used in conjunction with new radar capabilities from EISCAT_3D, modelling and in-situ spacecraft to pinpoint the onset region. You will use new and current missions such as the NASA THEMIS, Van Allen Probes missions and the new capabilities of imaging the Earth's magnetosphere from the upcoming ESA SMILE mission to determine where substorm onset occurs and, critically, why.