Journal Highlights

New insight into solar wind-magnetosphere-ionosphere interactions

Editor’s Highlight—

 

A Sudden Commencement of a geomagnetic storm (SC) is the result of the impact on the geomagnetic field of an abrupt solar-plasma front impacting the magnetosphere. The characteristics of the SC have been described for a long time. Using a combination of data from many satellites and ground-based instruments, this paper demonstrates for the first time that the relative importance of two wave modes, the fast and shear Alfvén modes changes as the disturbance moves earthwards. The latter is more relatively important closer to the Earth. This gives new insight into solar wind-magnetosphere-ionosphere interactions.