Yellowstone National Park, whose 3,500 square miles are mostly situated in Wyoming, is one of the most popular spots in the nation for nature lovers. But it also happens to sit atop a slumbering volcano with a history of massive eruptions, the most recent of which was at least 70,000 years ago.
Lately, the Internet has been rife with rumors that it's about to blow again, due to what some amateur prognosticators see as disturbing omens -- a March earthquake, an unusual release of helium from the park's hot springs and fumaroles, and bison that have been observed pushing outside the park's boundaries.
The scientists at the U.S. Geological Survey's Yellowstone Volcano Observatory reassure that there isn't anything unusual going on under the park, and that the odds are that it won't erupt for centuries. But when the volcano eventually does blow, they say, it's going to be a gigantic event that will spew enough ash to blanket the Rocky Mountains with a layer that could be several feet thick, and send particles across the entire country, with some even reaching far-away cities such as New York and Washington, D.C.