YELLOWSTONE NATIONAL PARK, Wyo. (AP) -- Scientists say the odds of another catastrophic volcanic eruption in Yellowstone within anyone's lifetime are extraordinarily remote, but that's exactly what happens in a made-for-television movie that will air this Sunday.

The docudrama, "Supervolcano," will be shown on the Discovery Channel.

The middle of Yellowstone is a huge caldera that last erupted 640,000 years ago. Other huge eruptions occurred 1.3 million and 2.1 million years ago.

Theoretically, the volcano could blow again.

"It's actually quite a well-done movie," said Bob Christiansen, former U.S. Geological Survey scientist-in-charge for the Yellowstone Volcano Observatory.

The producers consulted with Christiansen, and he said they worked hard to get the science behind the eruption right.

"It depicts the worst possible scenario that could conceivably happen," he said, "and it should be viewed in that light."

Hank Heasler, park geologist and the park's coordinating scientist for the volcano observatory, said any claim that Yellowstone is overdue for an eruption is based on simplistic reasoning, drawn only from when the three previous known eruptions occurred.

He compared that to predicting the temperature on a certain day in the future based only on the knowledge of temperatures on that day over the past three years.

"It is absolutely absurd to try to predict an interval of eruption," he said. "Such a method using just three data points is full of problems. It's the simple way to look at things, but this is not simple."

Heasler oversees a number of monitoring stations in the park and a range of scientific equipment measuring everything from ground tremors, ground shape, chemical changes in gasses, and water temperatures.

"There will be precursors," he said.

Christiansen suspects that the buildup to an eruption would be extended.

"In the movie, the eruptions occur within a few hours," he said. "I'd expect the signs and the blast to be longer-term."

"Supervolcano" has already aired in the United Kingdom and Christiansen and Heasler have viewed it. Most of the film was shot in Canada.

Information from: The Powell Tribune, http://www.powelltribune.com