Co-Rotating Magnetic Reconnection Site in Saturn's Magnetosphere

Using measurements from the Cassini spacecraft in Saturn’s magnetosphere, we propose a 3D physical picture of co-rotating reconnection site, which can only be driven by an internally generated source. Our results demonstrate that the co-rotating magnetic reconnection can drive an expansion of the current sheet in Saturn’s magnetosphere, and consequently produce Fermi acceleration of electrons. This reconnection site lasted for longer than one Saturn’s rotation period. The long-lasting and co-rotating natures of magnetic reconnection site at Saturn suggest fundamentally different roles of magnetic reconnection in driving magnetospheric dynamics (e.g., the auroral precipitation) from the Earth. Our co-rotating reconnection picture could also potentially shed light on the fast rotating magnetized plasma environments in the solar system and beyond.