A clay tablet that has baffled scientists for 150 years has been identified as a witness's account of the asteroid suspected of being behind the destruction of Sodom and Gomorrah. Researchers who cracked the cuneiform symbols on the Planisphere tablet believe that recorded an asteroid thought to have been more than half a mile across. The tablet, found by Henry Layard in the remains of the library in the royal place at Nineveh in the mid-19th century, is thought to be a 700 B.C. copy of notes made by a Sumerian astronomer watching the night sky. He referred to the...