Mullard Space Science Laboratory

Solar wind, space weather and space plasmas Earth’s magnetic field gives some protection from solar and galactic cosmic rays and from the solar wind. Reconnection can allow particles into the magnetosphere, both upstream of the Earth and in the magnetic tail. Tail reconnection can shoot particles towards and away from Earth, in violent ‘substorms’. The Earth-directed particles follow the magnetic field and, in the polar region, collide with atmospheric particles to excite atoms and molecules, producing the aurora. The auroral regions couple the magnetosphere to Earth’s ionosphere. Some of the particles become accelerated and trapped, adding to the Earth’s radiation belts. We make in-situ measurements in the Earth’s magnetosphere to study key physical processes, including reconnection, acceleration, shocks and turbulence. We study particle acceleration in the aurora, initiation of substorms and radiation belt particle acceleration, using Cluster, THEMIS (Time History of Events and Macroscale Interactions during Substorms) and MMS (Magnetospheric MultiScale). We also study the link between events on the Sun and in the solar wind and we will explore the link more through Solar Orbiter . We play lead roles in the Extreme UV imager and the Solar Wind Analyser on the mission. We are also very active in applied research, working with water companies, airlines and insurance companies to examine how space weather affects our daily lives. Coronal mass ejections sometimes reach out in the direction of Earth / ESA/NASA - SOHO/LASCO/EIT

What are the mechanisms for particle acceleration in the aurora and the role of wave acceleration in the radiation belts? What is the nature and origin of solar wind strahl, and the effect of solar wind discontinuities on the heliosphere?

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