* Astronomy

A magnitude 4.5 earthquake struck just before 8 p.m. about 7 miles east of Mount Rainier on Saturday night, but no injuries or damage were reported.

Scientists know Mount Rainier will eventually awaken as Mount St. Helens did in 1980. It could gradually build up and explode, or part of it may collapse. It could happen in 200 years, or it could happen tonight.

"People get burned by these kind of events because they think it can't happen in their lifetime" - Willie Scott of the U.S. Geological Survey.

The agency ranks Mount Rainier as the third most dangerous volcano in the nation, after Kilauea on Hawaii's Big Island and Mount St. Helens. Both are currently active.
Other studies call Rainier the most dangerous volcano in the world — not just for its explosive potential, but because of the 3 million people who live in the Seattle-Tacoma-Bellevue metropolitan area. At least 100,000 people live on top of Rainier mudflows that have solidified.
Mudflow poses a serious threat for Orting. Two rivers drain off the mountain, hug the town and converge just beyond it, putting Orting squarely in the mountain's strike zone. The town, in fact, was built atop a 500-year-old mudflow that buried the valley 9 metres deep.
Construction crews working on new housing developments for Orting's growing population have dug up massive tree stumps — remnants of a forest buried there the last time Mount Rainier rumbled.

The risk of catastrophe every couple thousand years has not stopped brisk development. But as scientists identified Rainier as a threat in the decades after Mount St. Helens' eruption, government officials and citizens have begun preparing.
Most of the mudflows — also called lahars — from Mount Rainier were triggered by an eruption. But the most recent, the Electron mudflow that buried Orting 500 years ago, did not seem to follow that pattern.