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What is space weather?

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Welcome to CoreFacts, where we're always short on time and big on science. I'm Jessica Robertson. Today's question is a good one.

What is space weather?

Space weather is the state of the environment in space near the Earth, including the solar wind and the Sun's magnetic field, the outer part of the Earth's magnetic field called the magnetosphere, and the part of the Earth's atmosphere called the ionosphere. All of these different parts of the near-Earth space environment can interact with each other dynamically, giving rise to occasional rapid variation in space-weather conditions, manifest at the Earth's surface as magnetic-field variation. The analogy with atmospheric weather, or meteorology, is a very loose one, but space weather, just like the weather we experience on the Earth's surface, can change over time. There are periods of calm and there can be stormy periods as well.

Working in partnership with other Federal Government agencies, the USGS Geomagnetism Program is an integral part of the National Space Weather Program. The nation's official information source for space weather is the National Oceanic and Atmospheric Administration's Space Environment Center, an agency that is an important customer of the USGS Geomagnetism Program.

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