Little Mercury May Be Shrinking Faster Than Scientists Expected

A new study suggests Mercury may have shrunk about 30% more than scientists previously thought, losing as much as 14 miles in diameter as its interior cooled and contracted over billions of years. “That’s significant for a planet barely 3,000 miles (4,900 kilometers) across,” reports the Associated Press. From the report: Mercury’s rough surface, continually reshaped by debris hurled from impact craters, may have hidden the true extent of the loss, according to the researchers whose findings appear in the journal Geophysical Research Letters.