Simulating Plasma Bubbles in Earth's Ionosphere

Satellites provide data and services that are essential to modern society. Our civilian, commercial, and defence capability rely on continued and assured access to space-based infrastructure. The space environment, however, is harsh and represents a significant threat to the operation of such satellites. Collision with space debris, damage to spacecraft components through electrostatic discharge, and communication disruption from atmospheric anomalies are daily threats facing satellite systems and their operators. Improving our ability to predict when the space environment will impact satellite systems is therefore crucial if we are to protect the essential services that rely on precise timing, positioning, navigation, and communication services.

A phenomenon in the upper atmosphere known as equatorial spread F can result in the unpredictable degradation or loss of satellite-based navigation and communication. The source of equatorial spread F is the formation of Rayleigh-Taylor plasma instabilities in the post-sunset equatorial F-region of the ionosphere, which generate these mesoscale plasma inhomogeneities (plasma bubbles) that interfere with the propagation of RF waves to and from satellites. The length and time scale of these plasma instabilities are small, grow non-linearly, are difficult to physically observe, and computationally challenging to simulate.

This project will incorporate a self-consistent ionospheric electrodynamics model and develop an improved method to treat the computational domain into an existing global circulation simulation model. The new simulation capability will resolve the critical physical processes governing the formation of Rayleigh-Taylor instabilities within the ionosphere and permit the study of ionospheric Rayleigh-Taylor instabilities as they evolve under a range of atmospheric conditions.

Contact:

Dr George Bowden g.bowden@adfa.edu.au

Dr Melrose Brown melrose.brown@adfa.edu.au

Supervisor(s)

Dr George Bowden g.bowden@adfa.edu.au

Supervisor