"The interior of the Earth is a problem at once fascinating and baffling, as one may easily judge by the vast literature and the few established facts concerning it." -- A. Francis Birch, geophysicist, 1952
National Geographic: Scientists to Drill Earth's Mantle, Retrieve First Sample?
It may not be a journey to the center of the Earth, but it could be the closest thing yet.
Scientists are planning to drill all the way through the planet's miles-thick crust to Earth's deep, hot mantle and retrieve samples for the first time. The samples, they say, would rival moon rocks for sheer scientific import—and be nearly as hard to get.
"That has been a long-term ambition of earth scientists," geologist Damon Teagle told National Geographic News.
But a lack of suitable technology and insufficient understanding of the crust have long tempered that ambition. (Get an overview of Earth's magma and other layers).
Now, better knowledge of the Earth's shell and technological advances—for example, a Japanese drill ship equipped with six miles (ten kilometers) of drilling pipe—have put the goal within reach, according to a commentary in this week's issue of the journal Nature, co-written by Teagle, a geologist at the U.K.'s University of Southampton.
Even so, drilling into the mantle would be "very expensive" and would require new drillbit and lubricant designs, among other things, according to the paper.
But if all goes as planned, drilling could begin by 2020, Teagle said. As soon as next month, the team will begin exploratory missions in the Pacific, where crews will "bore further into the oceanic crust than ever before," the paper says.