Heliospheric and Planetary Research 2023-2026

We will conduct a programme of research concerning the behaviour of fundamental plasma processes in the heliosphere and the role they play in shaping the space environment. The heliosphere is the region of space dominated by the Sun and the solar wind which flows out from it. We will use state-of-the-art plasma simulations, along with supporting spacecraft data, to reveal the role that turbulence plays in a variety of plasma processes throughout the solar system, such as particle energization, shock dynamics, and turbulence-driven magnetic reconnection. This combined programme of research will help answer some of the most important questions in space physics today such as: how energy flows through space to enable particle acceleration, how magnetic reconnection releases energy and generates structures at the smallest scales in the plasma, and how shock waves in a turbulent plasma are modified and accelerate particles. A key aspect is understanding the processes producing energetic particles in the heliosphere from flares to interplanetary shocks and planetary bow shocks. The research will enable us to link the variety of complex plasma structures we see to the roles they play in shaping the plasma environment throughout the heliosphere.

Our research will make use of data from the Magnetospheric Multiscale spacecraft, launched in 2015, which are making some of the highest resolution plasma measurements of near-Earth space, the Parker Solar Probe spacecraft, launched in 2018, which is spending 7 years sampling the Sun's plasma, the solar wind, from closer then ever before - down to 10 solar radii from the Sun, and Solar Orbiter, launched in 2020, which has comprehensive in situ and imaging instruments linking the Sun to the heliosphere and allowing solar wind evolution studies. As well as being of fundamental interest, the solar wind is also the link between the Sun and the Earth, driving the Space Weather that controls the Earth's magnetosphere, and which can have profound effects on technological systems such as satellites and communication networks. We will use data from Magnetospheric Multiscale to characterize the variety of kinetic plasma processes operating in the Earth's magnetosheath, such as waves, reconnection, and instabilities, and how these processes interact to generate the near-Earth space environment that we see.

Furthermore we will perform research which will help us understand the fundamental role that giant impacts play in planet formation. This work will use explicit simulations of giant impacts between bodies in the tidal environment of a massive primary to understand the formation and collisional evolution of planetary satellites. The results will be used to test collisional origin theories for the Uranian satellites, Cressida and Desdemona, and the Saturnian satellite Iapetus. Further, these results will be used to develop collision scaling relations in the tidal regime that are applicable in many contexts (e.g., satellite systems, short-period exoplanets and the accretion environment near white dwarfs).