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In 1953, CalTech geochemist Clair Patterson came up with an estimate for Earth's age that still holds today.
Author's Note: 10 Ways to Stop a Killer Asteroid
A few years back, I saw a TV program about the increased contact occurring between humans and sharks. There was one amazing shot that stuck with me: It showed an aerial view of swimmers just off the coast of Nags Head, and, unbeknownst to them, hundreds of sharks swam nearby. You could see their shadows among the bathers, dark and sinister. Had the people in the water known what was lurking nearby, they would have been on the beach in seconds. I feel the same way about NASA's NEO detection program. Are we better off knowing all those rocks are out there, circling us like sharks? Sometimes it seems better to be the oblivious bodysurfer who swims in ignorant bliss.
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