The object was first reported to the center about 10:15 p.m., and calls continued for more than an hour after that. Calls came from residents in at least five Midwestern states as the object tracked from west to east.
The object gradually got brighter until it lit up the whole night sky, going out in a blaze of glory as a fireball before dying out.
There was no evidence of any "touch down" of debris or remains hitting the ground anywhere in the Midwest, but in some sections of the region where the object was sighted, homes and trees shook and sonic booms were heard.
UW-Madison Assistant Professor Ankur Desai from the Department of Atmospheric and Oceanic Services said on Thursday morning he couldn't say for sure what the object was but it probably was a small meteor.
"These are relatively common events," Desai said. "This one put on a spectacular light show."
Mark Weller, an amateur astronomer from Waunakee, was standing in his kitchen shortly after 10 p.m. when he thought a bolt of lightning hit.
“My first reaction was gee, when do the clouds roll in,” he said. “(I) glanced out the kitchen window to see what ever it was disintegrate into half dozen or a dozen parts all screaming across the sky.”
Meteors are common, according to University of Wisconsin Space Place Director James Lattis, who did not see Wednesday’s event. But most are not as dramatic as the one reported Wednesday, he said.
“Even something relatively small, like the size of a golf ball, will light up the sky when it comes through,” he said. “They tend to disintegrate completely while they’re still many miles above the earth.”
The Weather Service said late Wednesday night that no official determination had been made as to what the object was, but there is a meteor shower currently happening.
"Gamma Virginids (the meteor shower) began on April 4 and is expected to last through April 21," the Weather Service said in a statement regarding the fireball.
"The peak activity for the meteor shower is April 14 and 15, and a large meteorite could have caused the brilliant fireball," the Weather Service said.
The Quad Cities National Weather Service in Iowa also caught a portion of a smoke trail from the fireball on its Doppler radar at 10:02 p.m. Wednesday, with the thin smoke trail extending across portions of Grant and Iowa Counties in Wisconsin.
"Several reports of a prolonged sonic boom were received from areas north of U.S. 20 (in Iowa), along with shaking of homes, trees and various other objects, including wind chimes," the Weather Service said.
Sources said the sonic boom was heard a good 15 minutes after the fireball blazed in the sky.
The fireball reportedly broke up into smaller pieces and was lost from sight.
Dane County Sgt. Tim Elve said deputies were dispatched to at least one location, in the town of Verona, where a resident suspected a meteorite might have landed, but as of late Wednesday, authorities hadn’t found any evidence of a landing.
The Air Force’s NORAD facility in Colorado tracks space junk — old satellites and such — that enter the Earth’s atmosphere, Lattis said, but no agency regularly tracks all meteors.
“Astronomers track big things, and you don’t even want to think about one of those coming close to the Earth,” he said.