While social media users offered every suggestion from alien invasion and missile testing to space junk and chemical trails, the Polk County Sheriff's Office began investigating the incident just before 5 p.m. Thursday as a potential plane crash, KPTV reported.
Polk County resident Richard Romano told KATU he was checking his mailbox Thursday when he heard a small plane flying overhead. He quickly took photos with his cellphone and contacted the sheriff's office thinking he had witnessed a small plane crashing into the timberline.
"I saw the airplane going the same path as the fireball was. Same exact path. In the time it took to get over there, for me walking and checking the mail, it gave him time to get right there where I saw the fireball. And I'm looking for the plane, and I don't see the plane anymore," Romano told the news station, adding, "I've seen meteors before, and they're bright white and in five seconds they're gone. That one lasted way too long."
After suspending its initial search around 9:30 p.m. Thursday, the sheriff's office resumed efforts early Friday supported by a LifeFlight Network helicopter, the Civil Air Patrol and the U.S. Forest Service, KATU reported.
Polk County Sheriff Deputy Lt. Dustin Newman told the news station the investigation turned up nothing to indicate "there's anything out there."
"We can say with confidence that it was not a plane crash. So, we think it was some type of natural event," Newman told KATU, adding, "It was obviously seen and reported in Polk County, and we've reached out to our neighboring counties and nobody has reported anything there."
Meanwhile. KPTV reported Jim Todd, director of space science education at the Oregon Museum of Science and Industry, said the occurrence could have been part of a meteor shower with the object in question starting off as big as a car but shrinking to the size of a baseball upon entering the earth's atmosphere.
"These fireballs or meteors occur almost every day, but most of them are so far up, we don't notice them. This one was large enough to survive the entry to the point that we could see it," Todd told the news station.
Of course, condensation trails, also known as contrails, became an instant favorite among online speculators, and Newsweek reported at least one scientific organization's observations support the instinct.
"The (American Meteor Society) and its international partners receive an average of 20,000 fireball reports every year. For the vast majority, these reports come from people who don't have any knowledge about meteors or general astronomy. As a result, we regularly receive reports that aren't related to fireballs or meteors but rather to the sun reflecting on contrails (short for 'condensation trails,')" Newsweek reported, citing the official AMS website.
The society’s site goes on to explain contrails are the “linear clouds etched across the skies by high-altitude airplanes” and notes both sunrise and sunset conditions often shade sunlight with “warm tones (red, orange and yellow) that some people may mistake for an astronomical event.”
In addition, the AMS contends true fireballs are fleeting, lasting only seconds, so any caught by someone with the time to pick up a camera and shoot photos is "certainly NOT a fireball," Newsweek reported.
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