The Canadian SuperDARN/PolarDARN facility

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The Sun provides the Earth with two types of energy. The first is the radiant heat and light energy needed to sustain plant (photosynthesis) and human life and to drive weather systems in the atmosphere near Earth's surface. The second type is the particle and magnetic energy carried from the Sun by the solar wind to Earth and deposited into the Earth's space environment, in the region called the magnetosphere where the particles are electrically charged and where are located hundreds of telecommunications satellites and an increasing number of astronauts for the Space Station and the Shuttle missions and future planetary missions. Through the telecommunication satellites, business transactions involving hundreds of millions of dollars are facilitated each day. The magnetosphere of Earth is its "space environment", in which the "space weather" can be nasty for both humans and satellites. During "magnetic storms", space weather conditions are very dangerous, so space walks are not performed and airline passengers are subjected to extra X-radiation in flights over the polar regions of the Earth. The study of the magnetosphere and space weather is greatly facilitated by the SuperDARN (Super Dual Auroral Radar Network) which, as of Nov. 2007, will consist of 21 radars, 14 in the northern and 7 in the southern hemisphere. These radars measure the convection pattern (the "wind" systems) in the space weather region. The newest pair of radars is the Canadian PolarDARN pair at Rankin Inlet (operating since May 11, 2006) and Inuvik (November, 2007). This SuperDARN pair is unique because it is designed to study the motion of the high latitude charged particles. These motions are driven mainly by "reconnection" between the solar wind magnetic field and Earth's magnetic field, in which some magnetic energy is converted to energy of motion of the charged particles in the magnetosphere. For the first time ever, ground-based radars (PolarDARN) will measure the reconnection-driven convection, which should lead to a much better understanding of space weather.