Mercury has a soft spot at its center
From Times Staff and Wire Reports
Researchers have cracked a mystery at the core of Mercury -- and say there’s molten fluid inside the tiny planet.
The finding, reported Friday in the journal Science, helps explain the discovery decades ago that Mercury has a small magnetic field. The discovery by the Mariner 10 spacecraft puzzled scientists, who believed that because of its small size the planet’s core had long ago solidified. But by carefully measuring variations in the planet’s spin, called librations, Cornell University researchers have concluded it must have a molten core.
