Drilling to center of the earth

Traveling to the center of the Earth is a fanciful concept, but consider the reality: We have so far drilled just 7.5 miles into the Earth's rocky crust, leaving roughly 3,962 more miles to go. The new Japanese research vessel Chikyu won't exactly breach Earth's core, but it will drill to an unprecedented depth, beginning in late 2007 when it embarks on its first scientific mission off the southwestern coast of Japan.

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