No one really knows the answer, and Lowenstern cautions that it may be if rather than when.
The Yellowstone volcano's first major eruption occurred 2.06 million years ago. A second eruption followed 1.3 million years ago and a third 640,000 years ago.
The series has led many to wonder whether it explodes about every 700,000 years, leaving the caldera primed for another blast.
Lowenstern, along with nearly all other scientists actively studying the volcano, says no. Three instances occurring at two intervals do not, statistically, mean anything.
The last eruption of any size was 70,000 years ago and was not nearly the magnitude of the three large eruptions, Lowenstern said.
Dozens of scientists around the United States will continue to monitor the volcano's behavior. They track the number and strength of earthquakes and record when the ground lifts even as little as a centimeter.
In mid-February, the Yellowstone Volcano Observatory said the ground near Norris Junction rose 3.5 centimeters during five months, an amount significant enough to report but not signaling potential catastrophe, Lowenstern said.
The observatory had to write a clarification soon after explaining that the movement was simply another change in a continually active system.
"When we work in a place that hasn't erupted in 70,000 years, you need to watch and wait and pay attention to what the Earth is saying," Lowenstern said.
While the Earth may still sputter and gurgle and spew, it might not ever erupt the way it has so many years ago.
"Yellowstone is the most recent system along the hot spot. There are older volcanic systems that march their way up the plains, and as they got older and older, all of those systems eventually cooled," Lowenstern said. "The ground subsided, and Hawaiian-type lava covered them up. Yellowstone will likely be a good place to grow potatoes one day."
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