An impact site, he noted, may resemble a divot on a golf course. The rocks could penetrate several inches in wet ground.
Over the next few weeks, Pugh and his colleagues will analyze all the reports they receive and plot out an area of potential impact.
They'll then hold public meetings in the region to tell people what to look for on the ground.
Any eyewitnesses of the fireball are encouraged to call the Cascadia Meteorite Laboratory at (503) 287-6733.
According to Mike Fergus, a spokesperson with the Federal Aviation Administration in Seattle, Washington, a private single-engine jet called in a sighting of the fireball Tuesday morning.
Several other pilots also reported seeing a bright flash.
"But nobody had seen the meteor body itself, nor the impact," he said.
According to the Adams County sheriff's office in Ritzville, Washington, early reports of an impact site in southeastern Washington are false.
Pugh noted that fireball sightings are relatively common in the Pacific Northwest, usually several times a year. Tuesday's, however, was bigger than most.
"This one was just exceedingly bright and produced an awful lot of noise," he said.
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