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My research will study the aurora, a beautiful display caused by energetic particles from space hitting the Earth's atmosphere at about 40 million mph. The aurora typically deposits 50 GW of power into the atmosphere, comparable to the electricity consumption of the UK. This huge energy source has considerable influence on the temperature and composition of the upper atmosphere, particularly in polar regions. The aurora is therefore one of many ingredients needed for computer simulations of the whole atmosphere, which predict changes to Earth's climate and to concentrations of gases such as ozone. Intense currents flow within and around aurora, heating the atmosphere just as an electric current heats a resistor. This heating has dramatic effects on the upper atmosphere, but several fundamental aspects remain undetermined. Previously it has been very difficult to measure the temperature of the atmosphere at auroral heights; it is too high for weather balloons, but too low for spacecraft. However, I recently made the exciting discovery, through experiment and theory, that the ratio of brightnesses of two specific auroral colours depends on the temperature of the atmosphere; therefore by observing these wavelengths in the aurora we can calculate the temperature. My idea is to use extremely sensitive cameras equipped with colour filters to make maps of atmospheric temperature, just like a thermal imaging camera. These temperature maps can be combined with radar measurements of the upper atmosphere to estimate the electrical conductivity, which is an important property influencing the flow of electric current through near-Earth space and the atmosphere. A computer simulation will help me to understand how different types of aurora are produced, what electric currents they generate, and how the aurora affects the temperature and chemistry of the upper atmosphere.