Volcano Chasers at Mt. Etna

July 28 -- Europe's most active volcano, Mount Etna, has been gushing lava for two weeks and today forced the airport in Sicily to close. But for volcano trackers it was a perfect time for a trek up the mountain.

In the past 24 hours, Mount Etna has been at its best. Scientists say it is as active as it was when it first erupted. The Italian military continued its fight to keep the lava away from Etna's ski resort. It is an amazing volcano and scientists say it could be a gold mine.

Borris Behnke is a German scientist, an expert on volcanoes. But out herehe is like a child.

Today, Behnke led this team of amateur volcano watchers to Mt. Etna's mostexplosive craters.

Just how big are the boulders coming out of the mountain?

"Well surely some of them are bigger than cars, and some might be as bigas trucks," said Behnke.

As spectacular as this crater looks during the day, at night it is almostbeyond description. For those who study volcanoes, walking up the mountain is an essential trip. Dozens of volcanologists from all parts of the world climb this mountain everyday. This eruption, Behnke says, will be the most studied of all time.

"It will probably make us learn more about the dynamics of Etna andabout the storage and transport of magma in the volcano than we've hadbefore," said Behnke. "We will probably learn more about this volcano during thiseruption than had been learned in 3,000 years."

One reason — hundreds of monitoring devices planted around the volcano send a constant stream of data to scientists a few miles away. They analyzethe gases coming from the craters. They track the flow of lava and measureseismic activity. In the days leading up to this eruption there were morethan 2,600 small earthquakes centered on the volcano. Even for Etna, thatis remarkable.

Behnke said this is a complicated eruption becuase the lava is shootingout from so many places on all sides of the volcano. For scientists acomplex eruption is a gold mine.