First ever supercomputer simulations of Mars with a fully molten core could explain the Red Planet's unusual magnetic field. Billions of years ago, Mars had an active magnetic field. Mysteriously, its ...

Like Earth, Mars once had a strong magnetic field that shielded its thick atmosphere from the solar wind. But now only the magnetic imprint remains. What's long baffled scientists, though, is why this ...

Deep beneath our feet, far beyond the reach of drills or submersibles, Earth hides a solid metal heart that behaves in ways geophysicists have struggled to explain. New experiments now suggest that a ...