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"Space weather refers to conditions on the Sun and in the space environment that can influence the performance and reliability of space-borne and ground-based technological systems..."-National Space Weather Prediction Center (1995)

      Strangely, it is not a well know fact that the earth is being constantly subjected to an incredible amount of electromagnetic radiation at any given point in time. This is due to the phenomenon known as the solar wind. The Sun constantly radiates matter and magnetic fields into space, bombarding planets in the solar system, and while the most apparent effect of this is visible light which can penetrate the atmosphere much of the other waves, especially extreme-ultraviolet and x-rays, are dissipated into energy in the upper atmosphere or are repulsed by the magnetosphere, the magnetic field which surrounds the Earth . Evidence of this can be seen on Earth, Saturn, Jupiter, and several other astronomical bodies in the form of auroras which form around the magnetic poles. Planets without magnetic poles, such as Mars, also exhibit evidence of the solar wind. In the case of Mars, this is seen in the stripping away of the outer atmosphere, demonstrating the importance of magnetic fields.
      The magnetic aspects of this constant stream of energy are particularly interesting when considering electronics and communications, which, when exposed to them, can suffer signal degradation and reduced functionality. The Earth's surface has a normal magnetic field strength, (in Teslas), of about 50uT,  the average solar wind about 6nT, and the average solar magnetic field is about 100uT. Additionally, solar wind can cause geomagnetic storms which form fields around 1uT in strength. These magnetic fields have been shown to limit transistor operation and cause unexpected induction in electrical systems, albeit seeming small in relation to physical magnets, (e.g. refrigerator magnets have a field of about 7.5mT). The most important difference between the two is that the effects of the solar wind, the solar field, the geomagnetic field, and geomagnetic storms are global, and thus able to effect very large systems such as power grids, and communications networks. After all, a performance drop of 1% globally will still be an enormous reduction in efficiency.