Module description
Examines in detail the physics of our nearest star and of its interaction with the Solar System. Topics covered include the Sun's structure, energy production and transport processes, solar activity, the solar wind and its interaction with planets and comets.

Learning outcomes
After taking this module students should be able to:

• understand the source of the Sun's energy;
• follow the flow of energy through the different zones of the Sun's interior;
• explain how helioseismology and neutrino counts give information on the Sun's interior;
• recognise different features on the surface of the Sun under quiet and active conditions;
• appreciate the problem posed by coronal heating;
• describe how to measure the electron density and velocity of interplanetary space;
• derive Parker's simple theory of the solar wind and list its limitations;
• summarise the structure of a comet, and demonstrate the relationship between comets and meteor showers.

Additional learning activities
Use of solar telescope to observe sunspots.

Outline syllabus
Sun (5) :
Structure of the Sun. Nuclear processes in the core. Solar neutrinos. Radiative and Convective zones. Solar seismology. Photosphere and Chromosphere.

Solar Activity (5) :
Sunspots, faculae, plages, prominences, filaments. Babcock-Leighton theory. Flares. Solar radio emission. Bursts. X-rays. Particle emission.

Interplanetary Medium (5) :
Corona. Coronal Heating.
Plasma density in corona and interplanetary space :
Scattering of light in the solar corona. Space-craft measurements.
Irregularities in corona and interplanetary space : Coronal features, interplanetary scintillations.
Dynamics of corona and solar wind: Movement of visible features in the corona. Doppler shift of radar echoes.
Comet tails. Interplanetary scintillation.

Solar wind (4) :
Parker's theory. Solar breeze and solar wind. Effect of conductivity and viscosity. Spiral structure of Interplanetary magnetic field. Acceleration of solar wind near sun. Non-uniform flow and shock fronts. Terminator Shock.

Comets and Meteoroids (1) :
Structure of Comets : Core, Coma, Cloud, Dust Tail, Plasma Tail and Ion Loading. Comets and Meteor Showers.