Mars Update: Barren planet once hummed with magnetism, leaving "tattoos"
University of DelawareThe cold, barren crust of Mars conceals ancient remnants of its fiery youth 4 billion years ago, when an "active dynamo" in the red planet's interior hummed with magnetism, much like Earth, researchers report April 30 in Science. Like faded tattoos on an aging space sailor, magnetic stripes now adorn the Martian crust, perhaps where sea floors spread apart.