The Earth is always vulnerable to impacts by comets and asteroids, but giant impacts are rare, with the last major collision taking place 65 million years ago, ending the Age of Dinosaurs.
Still, astronomers do monitor the sky for near-Earth objects.
"There are no known near-Earth objects in 2012 that present a credible risk to Earth," Yeomans said. "None, zero, zip, nada."
But despite evidence to the contrary, doomsdays theorists have garnered attention, and similar prophecies will continue to proliferate unless scientists become more involved in bringing truth to these outlandish claims, Yeomans said.
Mounting hysteria regarding these unfounded doomsday predictions "will improve only if scientists get more engaged in debunking pseudoscience," he said.
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