Roy; every nation on Earth is aware of the presence of unexplained stuff going on up there. Publicly, they pretend to disbelieve, but privately they only pretend to disbelieve. (No typos in the last sentence).
I did make a mistake in my 22.36. It should have read
"Publicly, they pretend to disbelieve, but privately they only pretend to pretend to disbelieve."
I think it's aliens. They've clearly crossed the galaxy using technology beyond our understanding to float an object about the size of a small car over Canada at 40mph.
..and then let it be shot down.
The aliens don't need to cross the galaxy, they live on Mars. But after the widespread US panic caused by H G Wells radio broadcast War of the Worlds in October 1938, the powers-that-be daren't reveal it, so they perpetuate the scientific myth that Mars cannot support life.
Lots of nations launch weather balloons that go on to drift beyond their territory.
That the US are shooting some down now is more about sending a signal to China that the US will defend itself and its allies if China attacks.
The balloons are harmless and pose no threat, but they are in theory violating US airspace, so the yanks can use them for target practice.
// Heidi Taylor from the Tangaroa Blue Foundation, which cleans up marine debris across the country [Ausralia], recently came across partially degraded weather balloons on the Cocos (Keeling) Islands, more than 2,100 kilometres off the WA coast.
The BOM releases about 56 balloons each day from dozens of locations around Australia and its offshore territories, including Antarctica. //