Two NASA satellites rocketed into orbit from California aboard a SpaceX Falcon 9 rocket Wednesday, commencing a $170 million mission to study a phenomenon of space physics that has eluded researchers since the dawn of the Space Age.
The twin spacecraft are part of the NASA-funded TRACERS mission, which will spend at least a year measuring plasma conditions in narrow regions of Earth's magnetic field known as polar cusps. As the name suggests, these regions are located over the poles. They play an important but poorly understood role in creating colorful auroras as plasma streaming out from the Sun interacts with the magnetic field surrounding Earth.
The same process drives geomagnetic storms capable of disrupting GPS navigation, radio communications, electrical grids, and satellite operations. These outbursts are usually triggered by solar flares or coronal mass ejections that send blobs of plasma out into the Solar System. If one of these flows happens to be aimed at Earth, we are treated with auroras but vulnerable to the storm's harmful effects.