A Possible Cause of Magnetic Anomalies on the Southern Martian Hemisphere

From the topology of a synthetic aurora map, we propose a mechanism for the magnetic anomalies on the southern martian hemisphere, i.e., impacts by asteroids when the dynamo is active. The quasi concentric circles of aurora suggest that there are two-to-three convectional cells for each impact. The whole synthetic aurora is induced by three major impacts of asteroids. The east–west lineation features of crust magnetizations are due to the east–west trending locations of three impacts. The alternatively changed sign of crust magnetization originates from the alternatively changed flow direction on the tops of adjacent convectional cells.