Even though the center of the earth is closer to New York City than New York is to Honolulu, it is as inaccessible to scientists as the stars. Until recently, the earth's core, hidden under thousands of miles of rock, was a mystery. Now all that is changing. In the past two years, thanks to a technological revolution in methods of observation, scientists have begun to paint a theoretical portrait of the planet's interior in startling detail. Says Harvard University Geophysicist Adam Dziewonski: "For the first time we can actually see the inside of the machine."
What they "see" is astounding....