United States officials have admitted the three mysterious objects shot down in the last week were likely "benign" — and that the first missile fired at one of them missed its target.
The US military's first shot at the unknown object over Lake Huron "landed harmlessly" over the Canadian border.
White House national security spokesperson John Kirby said: "The intelligence community is considering as a leading explanation that these could just be balloons tied to some commercial or benign purpose."
Here's what we know so far.
What does 'benign' balloon mean?
It's not entirely clear whether "benign" means civilian drones, commercial or advertising balloons, or something else — but Mr Kirby did elaborate a little.
He said a "range of entities", including countries, companies and research organisations, send objects up to that height for "purposes that are not nefarious at all".
Canada's defence minister described the one shot down on Prime Minister Justin Trudeau's orders as a "small, cylindrical object".
Mr Kirby also hinted the objects were substantially different from the spy balloon, specifically in size.
Beyond that, there have been very few details about the objects or what they might be.
What we do know is there's no indication the objects were part of any bigger surveillance operation.
"We don't see anything that points right now to being part of the [People's Republic of China] spy balloon program," Mr Kirby said.
Conspiracy theories are also running rampant that the devices are a ploy to distract Americans from everything from immigration to the war in Ukraine to the chemical spill in Ohio.
Online posts about aliens have also increased by almost 300 per cent since the spy balloon was identified, according to Zignal Labs, a San Francisco-based media intelligence firm.
Have they recovered the objects shot down?
Officials are still in the process of recovering debris from the spy balloon, but haven't got to the other objects shot down after that.
Recovery efforts have been hampered by weather conditions and remote locations they've landed in.
It's tipped to be quite a while before they're found.
"The one off the coast of Alaska, that's in some really, really difficult terrain," General Milley said.
"[It's in] the Arctic circle, with very, very low temperatures in the minus 40s."
One of the objects is in the Rocky Mountains in Canada's Yukon, and the latest is in Lake Huron, which has an area of almost 60,000 square kilometres.
First missile missed object flying over Lake Huron
The F-16 jet ordered by President Joe Biden to shoot down the object flying over the US-Canada border missed its first of two attempts.
General Mark Milley, chairman of the Joint Chiefs of Staff, said despite the misfire they had been "very, very careful" to make sure the shots "are in fact safe".
"And that's the guidance from the president," he said.
"Shoot it down, but make sure we minimise collateral damage and we preserve the safety of the American people."
The missile landed in the water of Lake Huron.
"We certainly tracked it all the way down," General Milley said.
The government is now facing scrutiny over whether it's causing unnecessary risk by shooting down objects that aren't a security threat.
This was despite letting what officials described as a Chinese spy balloon traverse across much of the country before taking it down.
More mystery balloons sighted over Europe
More unidentified objects with "characteristics similar to a weather balloon" have been reported in the skies over Romania and neighbouring Moldova.
Romania scrambled military jets and Moldova shut down its airspace temporarily on Tuesday local time. Both countries border Ukraine.
Romania's defence ministry deployed two jets to the country's south-east to hunt down the object, detected 11,000 metres overhead.
"The crews of the two aircraft did not confirm the presence of the aerial target, neither visually nor on the onboard radars," a ministry statement said.
The jets, both under NATO command, stayed in the area for 30 minutes but couldn't find the object.
