Introductory description

Our knowledge of what is happening in the Sun is increasing rapidly, largely as a result of space-based instrumentation. The challenge is to understand it. The basic process is simple: Heat moves outwards from its source at the centre (nuclear fusion). However, on its way out, this energy drives processes on many different length scales many of which are not well understood. For example, there is still no convincing theory of how the Sun's magnetic field is generated and how the atmosphere is heated.

The module starts by stating the basic properties of the Sun as deduced from observation and general physical principles, and introduces a hydrodynamic model of the Sun. This treats the solar matter as a fluid. There are the usual gravitational and pressure gradient forces governing the fluid motion but, because the constituent particles of the fluid are charged, there are also electromagnetic forces. As a result, we need to worry about Maxwell's equations as well as Newton's laws. The module then discusses applications of this theory, called magnetohydrodynamics, to model and understand phenomena like sunspots, coronal loops, prominences, solar flares, coronal mass ejections and space weather.

Module web page

Module aims

Outline syllabus

This is an indicative module outline only to give an indication of the sort of topics that may be covered. Actual sessions held may differ.

1. An outline of observational properties ranging from the solar interior ot the Sun's outer atmosphere
2. Theoretical aspects of solar magnetohydrodynamics (MHD)
3. Magnetic equilibria. Stratification. Force-free magnetic fields. Magnetic arcades, prominences, suspots, intense flux tubes.
4. MHD Waves. Helioseismology.
5. Solar flares. Heating of the solar corona. Coronal mass ejections and space weather.

Learning outcomes

By the end of the module, students should be able to:

• Describe the structure of the Sun and the main features and phenomena observed on the solar surface and in the solar atmosphere
• Describe the physical processes at work in the sun
• Demonstrate understanding of the dynamic processes operating in the Sun, in terms of MHD

Indicative reading list

Priest E.R., Solar Magnetohydrodynamics; Reidel; 1982.
Golub L., and Pasachoff J.M., Nearest Star: the Surprising Science of our Sun; Harvard Uni. Press; 2001.

View reading list on Talis Aspire

Subject specific skills

Knowledge of mathematics and physics. Skills in modelling, reasoning, thinking.

Transferable skills

Analytical, communication, problem-solving, self-study