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What is Space Weather? It can make even the most destructive tornado here on Earth look like a gentle breeze. Eruptions from the Sun, the disturbances in the solar wind, and the twisting and stretching of Earth's magnetic field: collectively, we call it space weather. And, just like weather here on Earth, it can be both mild-and wild.  
  A view of the Aurora Australis -- the Southern Lights -- taken from the Space Shuttle Discovery in 1991. The tail of the shuttle can be seen to the left. Photo courtesy of NASA.

Everyone is familiar with changes in the weather on Earth such as rain, snow or a powerful hurricane. But faraway changes on the Sun and in Earth's magnetosphere can cause another sort of weather that can effect life on Earth: Space Weather.

There are four realms in our Sun-Earth Environment:

A powerhouse of energy and the source of the solar wind roaring through space Full of charged particles and plasma spread by solar wind, marked by invisible magnetic fields.
A giant magnetic field surrounds Earth, pushed out of shape by the powerful solar wind. Layers of air shield us from killer rays and solar wind, but magnetic storms and the aurora prove there's contact

Stormy Weather: The Sun-Earth Connection

Just as it effects weather on Earth, the Sun is responsible for disturbances in our space environment as well.

Besides emitting a continuous stream of plasma called the solar wind, the Sun periodically releases billions of tons of matter in what are called coronal mass ejections . These immense clouds of material, when directed towards Earth, can cause large magnetic storms in the magnetosphere and the upper atmosphere.

Magnetic storms produce huge amounts of power - several million megawatts - more than enough to power the United States. Magnetic storms are a series of geospace disturbances -- namely, auroral activity, increase in the radiation levels in the inner magnetosphere, and rapid changes in Earth's magnetic field -- caused by increased energy input from the solar wind.

Magnetic Storm Effects:

  • Aurora borealis, the northern lights, and aurora australis, the southern lights.
  • Radio and television interference and blackouts
  • Hazards to orbiting astronauts and spacecraft
  • Power Grid Failures

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  The Space Weather Center is brought to you by the Space Science Institute as part of the National Space Weather Program. Funding is provided by NASA and the National Science Foundation.  

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