Japanese Supercomputer Model (IMAGE) Kyoto University Caption On the left is and aurora oval before the auroral breakup occurs On the right is a supercomputer simulation reveals how auroral breakups develop Hot charged particles, or plasmas, gather in near-Earth space -- just above the upper atmosphere of the polar region -- when magnetic field lines reconnect in space. This makes the plasma rotate, creating a sudden electrical current above the polar regions. Furthermore, an electric current overflows near the bright aurora in the upper atmosphere, making the plasma rotate and discharge the extra electricity. This gives rise to the 'surge', the very bright sparks of light that characterize substorms. Credit Kyoto University Usage Restrictions Please credit Kyoto University. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.