POLK COUNTY — A “fireball” reported over Polk County on Thursday was most likely a “contrail that got a lot of attention,” said Jim Todd, director of Space Science Education at OMSI.
“I know people will be kind of disappointed, but it’s something we learn from,” Todd said. “We can’t take one data alone; it takes multiple data to come to a conclusion. The more data you have, the better results you can come out with. It’s nice that people are looking.”
The initial report came through as a 911 call, Sheriff Mark Garton said.
“A guy was outside and had heard an airplane — what he thought was an airplane,” he said. “And then heard a boom. He looked up and saw this fireball right where the plane was.”
He managed to grab a couple of photos of the “fireball.” Garton said because they thought it might be a plane, deputies coordinated a search for wreckage.
“We called LifeFlight, because they’d offered to help us in the past, just to see if there was wreckage,” Garton said. LifeFlight has an infrared type of device, and didn’t see anything register on that either, Garton said.
Someone commented on the sheriff’s Facebook page suggesting it was debris from the international space station. Todd said that was unlikely.
“It would have been national news,” Todd said. “Anytime there’s just debris from a man-made satellite, it would have left a trail that would have lasted probably 10 seconds across the sky, and it would have been reported, meaning NASA or China or European space agencies would have reported that such-and-such has entered the atmosphere and burned up.”
Todd said it had an illusion of being a fireball, because it was at sunset.
“Two things were in play,” he said. “We just passed leonids meteor shower, a major meteor shower, but that object isn’t until sunrise.”
The so-called unicorn meteor shower was happening in Europe, so that was ruled out also, Todd said.
One reason Todd said the sight was likely a contrail is that no other pictures or video exist.
A fireball is an object that is very likely an asteroid entering the Earth’s atmosphere, Todd said. It can be the size of a basketball or a grain of sand. When it enters the atmosphere at a great speed — about 15,000 mph — it creates friction and pressure, which creates the light show.
However, this happens at 50 or 60 miles up.
“At that distance, you can see most of Oregon,” Todd said. “Everybody would have noticed it.”
From the Coast to Portland and Eugene, people would have seen it.
Another thing that ruled out a fireball: It didn’t register on Doplar radar.
“Doplar is a very good source, because it will show up,” Todd said.
Todd noted that the Earth is bombarded by debris every day, but most of it burns up before it gets through the atmosphere. When it does reach the surface, often it falls into the water unseen.
Todd said that he did not see this incident himself, just the one photo.
“If somebody has a video, please send it!” he said.