Magnetic field of Mars – Københavns Universitet

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Magnetic field of Mars

Today Mars has no internal magnetic field of global extent, but regions of the crust are strongly magnetized. These magnetic anomalies in the crust are believed to have formed when iron bearing minerals acquired magnetic remanence while a core dynamo was active on Mars.

From measurements of the magnetic anomalies in areas, impact craters and volcanic structures of different age, the internal dynamo is believed to have ceased sometime between 3 and 4 billion years ago.