Want more? Subscribe to NASA on iTunes! http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=283424434 NASA’s THEMIS mission has overturned a longstanding belief about the interaction between solar particles and Earth’s protective magnetic field. This new discovery could help scientists predict when the solar storms that can disrupt power grids, satellites and even GPS signals, could be especially severe. For more information: www.nasa.gov/themis Less