WASHINGTON, Feb 15 (Reuters) – Weather balloons, civilian drones and other non-military aerial vehicles are all possible explanations for the mysterious objects the US military has shot out of the sky over the past week, scientists and atmosphere experts say.
US and Canadian officials have offered scant details of exactly what warplanes shot down over Alaska, northwestern Canada and Lake Huron three days after an earlier downing of a suspected Chinese spy balloon off the coast of South Carolina.
However, one thing is clear: there are many non-military objects floating high in the atmosphere.
“Every day around the world, hundreds, probably nearly 1,000 balloons are launched to make meteorological observations for countries around the world,” said Raymond Shaw, an atmospheric physicist and professor at Michigan Technological University. “They’re a good way to take atmospheric measurements without spending a lot of money.”
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The US military and the Biden administration have admitted they don’t know much about the latest unmanned objects, including how they stay aloft, who built them and whether they may have gathered intelligence.
Military officials say it’s unlikely they’ll know for sure what the objects were until they’re able to recover the debris.
On Tuesday, White House national security spokesman John Kirby said US intelligence agencies are considering the possibility that the aircraft could be “connected to a commercial or benign purpose.”
Balloons are one possible explanation.
Scientists use balloons to study wind patterns, air quality, and other aspects of Earth’s atmosphere. They come in many sizes, from a few meters in diameter to the width of a tennis court. Some climb up to 100,000 feet on vertical missions before bursting, and many can travel hundreds of kilometers, typically dangling sensor payloads on cables or cords below.
Some high-altitude balloons used to study stratospheric wind speed and direction only carry a GPS tracker, said Alemu Gonsamo, an assistant professor at Canada’s McMaster University, who uses camera-equipped balloons to survey vegetation on the ground investigate.
The object shot down over Canada on Saturday was described by Canada’s defense minister as resembling a balloon. But the other two objects could have been something else entirely.
For example, a US official described the object shot Sunday over Lake Huron as octagonal with dangling strings.
“The Pentagon shooting at an octagon? It couldn’t be a balloon because, by definition, a balloon has a soft boundary, so it must be smooth,” said Alex Kostinski, a physicist at Michigan Tech University.
In Alaska, where one of the objects was shot down, scientists are conducting field programs to deploy large balloons and rockets from warehouses and launch pads at the Poker Flat Research Range, said John Walsh, an arctic climate scientist at the University of Alaska Fairbanks.
“But I don’t think any of those field programs are running right now, so that wouldn’t explain what’s been launched in the last week or so,” Walsh said.
Little is known about the object shot down over Alaska on Friday, which a Pentagon spokesman described as the size of a small car, and which was struck by a missile about 40,000 feet above the ground.
Some large consumer or commercial drones with propellers can be as big as a small car and on rare occasions reach an altitude of 40,000 feet, although the US Federal Aviation Administration discourages consumer drones from flying higher than 400 feet.
Research drones deployed in Arctic regions are sometimes preferred over satellites to get a more accurate, longer-term view of the effects of melting ice and sea-level rise, NASA says, but these aircraft are limited to just a few hours in the air.
Drones were among the objects studied by a NASA study team formed last year to help the Pentagon understand unidentified aerial phenomena, said Thomas Zurbuchen, NASA’s former chief of science, who oversaw the group before joining the retired in December.
After the Chinese balloon incident, the US military adjusted the filters it uses to examine the radar data, allowing it to detect smaller, slower-moving objects. That will inevitably mean more sightings and possibly more kills.
US Senator Marco Rubio, who left a secret briefing on the objects on Tuesday, told reporters they are no different from the hundreds of benign objects cited in previous intelligence reports.
“We’ve never shot down anything in NORAD for over 65 years, and in one week they shot down three things,” he said.
Reporting by Joey Roulette Edited by Don Durfee and Alistair Bell
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