Space and planetary physics 2022-2025

We will undertake a broad programme of work studying the Sun, interplanetary space and several of the planets and moons in our Solar System. We choose projects that address some of the most fundamental processes that exist in space: as a result, many aspects of our work can be applied to other solar systems, or other space environments throughout the Universe. We also study aspects of interplanetary space that will ultimately help us better predict conditions there, and especially those near the Earth, where they can harm astronauts and damage satellites and even electrical systems on the ground. In this way, we help to predict such "space weather" and improve society at large.

Space is filled with small amounts of charged particles, called a plasma, along with magnetic and electric fields. One fundamental process that occurs in space plasmas is magnetic reconnection, which occurs on very small scales but releases magnetic energy and accelerates particles on large scales. We will study spacecraft measurements of reconnection and determine how energy is converted and transported around reconnection sites.

At the very large scale, coronal mass ejections are released from the Sun and can cause space weather effects when they arrive near the Earth. We will use measurements from many spacecraft to study how these structures evolve as they travel through the solar system to better understand the space weather risk.

We will use the same set of spacecraft, some of which travel very close to the Sun, to study small scale structures in the solar wind plasma that flows away from it. These "switchbacks" carry energy into space, but their source on the Sun is unknown.

We will also analyse some of the very smallest scales in the solar wind, over which protons gyrate around the magnetic field, and simulate their behaviour in order to understand how the distribution of particles evolves as the they travel away from the Sun.

We are also interested in the environment around planets and moons in the solar system. Ganymede is a moon of Jupiter, the largest planet in the solar system. Ganymede is a high priority science target because it is the only moon known to have a magnetic field and one of very few to probably have a subsurface ocean. It interacts with Jupiter's plasma and magnetic field and we will develop an advanced model to simulate this interaction.

The closest planet to the Sun, Mercury, also has a magnetic field and as it interacts with the solar wind flowing past, many waves are generated. We will study how these waves can accelerate particles around the planet.

We have a long history of studying the gas giant planets of the outer solar system. At Saturn, we will study waves high in its atmosphere; such waves also exist at the Earth and by studying those at Saturn, we will learn about the global circulation of Saturn's atmosphere and how it couples into space around the planet.

Finally, we will improve the way that we can run computer simulations of space around the outer planets. Working with modellers we will use our theoretical knowledge to include several key physical effects into the models so that we can improve their quality and predictive power.