A loud explosion and bright flash that lit up the sky Monday evening in Beltrami County was likely not a meteor. But after conferring with NASA and other agencies, officials remain baffled about what it was.
"Honestly I do not know, and the scientists and astronomers that I was talking to were kind of puzzled as well," said Christopher Muller, director of Beltrami County Emergency Management and its public information officer.
The determination is a reversal after the county initially reported it was "likely" a meteor caused the flash in the north-central Minnesota county. Agencies began investigating after videos captured the unusual occurrence and reports of an explosion came in around 6:40 p.m. Monday.
"This boom rattled windows, shook houses and was heard across much of southern Beltrami County," according to Beltrami County Emergency Management.
County officials shared a video on their emergency management Facebook page that was captured by the home surveillance camera of a resident in Bemidji's Nymore neighborhood.
The video showed a bright white flash, followed by an explosion three seconds later. An analysis of the video found the source of the explosion was less than a mile away, and was seen only in a 50-mile area.
In consulting with experts, Muller said it was likely not a meteor because it would have been observed much farther away — and would be heard as far away as Duluth, 150 miles from where the video was taken.
"We've gotten absolutely no indication that it was [heard] anywhere near there," he said.
A meteor also would have produced a much longer pause between the light flash and the loud explosion because it comes from high in the atmosphere and sound travels much more slowly than light, said Dr. Jennifer Mitchell, a planetary geologist at the University of Minnesota who researches meteorites.
While she agrees with the reasoning, Mitchell said it does have the hallmarks of a fireball created by a meteor entering Earth's atmosphere.
Nine known meteorites have fallen in Minnesota, she said.
She urged Minnesotans to submit photos of any possible meteorites they come across for research purposes.
"If they are walking around and they see a weird dark rock on the floor that wasn't there the day before, take a photo of it send it in," Mitchell said.
The footage was exciting for the tight-knit community of meteorite researchers in Minnesota, Mitchell added, noting that her colleagues on Tuesday were analyzing the footage and checking the math.
After NASA and other groups looked at another video captured by the Bemidji Regional Airport security camera Monday evening, it was determined the object streaking from the center and right side of the camera frame was too horizontal for them to be confident it was a meteor. He said the team investigating is "leaning towards" finding it has no relevance to the first video's explosion.
County emergency officials looked into whether the event was an explosion on the ground but found nothing and no power outages.
Staff writer Faiza Mahamud contributed to this story.
