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- Coronal mass ejections occur at a rate of a few times a week to several times
- per day. If a CME erupts on the side of the Sun facing Earth, and if our orbit
- intersects the path of that cloud, the results can be spectacular and sometimes
- hazardous. CMEs cause disturbances in the magnetosphere, which trigger auroras,
- make magnetic navigation at high latitudes difficult, and sometimes cause
- current peaks in high-voltage power lines, resulting in power outages and
- occasionally in the destruction of power equipment. They can also damage or
- destroy Earth-orbiting satellites.
-
- Fortunately, our planet is protected from the harmful effects of the radiation
- and hot plasma by our atmosphere and by an invisible magnetic shell known as the
- magnetosphere. However, some energetic particles do enter the magnetosphere from
- time to time, funneling in near the North and South Poles, where the magnetic
- field is weakest and the magnetosphere is partially open to space. The rain of
- plasma into our magnetosphere can induce magnetic storms and produce the
- phenomena known as auroras.
-