“These sources could be energetic impacts or core motion generated by gravitational interactions with ancient satellites which have since then disappeared.”

So are we saying that Earths magnetic field could be a result of having the moon?

“These layers, if widespread, can have pretty big consequences for the rest of the planet,” Lekic said. “Their existence can help tell us whether magnetic fields can be generated and maintained, how planets cool over time, and also how the dynamics of their interiors change over time.”

They think its possible to bring back Mars magnetic field?