Number 12 (Story #2), December 10, 1990 by Phillip F. Schewe and Ben Stein ASTEROID IMPACTS KILLED THE DINOSAURS : Although some scientists consider volcanoes and other phenomena to have contributed to the mass extinctions at the KT boundary, the impact explanation was shared by all the panelists at an AGU session devoted to the subject. "A few years ago, our problem was that we didn't have any craters to point our fingers at, whereas now we've got several," said Walter Alverez of UC Berkeley. "So now, maybe instead of a smoking gun we've got a smoking firing squad." At the session several scientists offered differing impact-related extinction scenarios featuring broiling-hot particles, acid rain, and tidal waves. (Los Angeles Times, December 5, 1990.)