http://spaceweather.com/
Dec. 3, 2003:Â Earth is surrounded by a magnetic force field--a bubble in space called "the magnetosphere" tens of thousands of miles wide. Although many people don't know it exists, the magnetosphere is familiar. It's a far flung part of the same planetary magnetic field that deflects compass needles here on Earth's surface. And it's important. The magnetosphere acts as a shield that protects us from solar storms.
According to new observations, however, from NASA's IMAGE spacecraft and the joint NASA/European Space Agency Cluster satellites, immense cracks sometimes develop in Earth's magnetosphere and remain open for hours. This allows the solar wind to gush through and power stormy space weather... http://science.nasa.gov/science-news/science-at-nasa/2003/03dec_magneticcracks/
About Real-Time Magnetosphere Simulation
http://www2.nict.go.jp/y/y223/simulation/realtime/index.html
