It’s intriguing. Reports of unidentified flying objects being shot down over Alaska, Canada, and Michigan prompts a lot of questions.
The Earth’s atmosphere eventually becomes space at 100 km up. The Kármán line is one way to define the boundary. All aeronautic activities are deemed to take place below that imaginary line. Theodore Karman did his best to determine a height at which the Earth’s atmosphere is too thin to support flight. Now, there’s an international discussion about bringing that boundary down to 80 km. That is the hight above which a person in a space vehicle is said to become an astronaut.
I guess my point is that there’s a lot of the Earth’s atmosphere to continuously monitor, if the task is to know about everything that is flying everywhere. So, it’s perfectly reasonable that reports of unidentified flying objects will crop up, now and then.
It doesn’t mean that there are alien probes popping in to keep an eye on us earthlings. No, in so far as is commonly known there’s no evidence that stands up to scrutiny to definitively prove the existence of sustained airborne craft that are not of this Earth. However, extra-terrestrial objects fall to Earth all the time. Mostly ice and rocks. I wrote about objects falling from the sky in an earlier article.
It’s worth recalling the first article of the Chicago Convention on Sovereignty:
The contracting States recognize that every State has complete and exclusive sovereignty over the airspace above its territory.
For those monitoring what’s in the air, the primary concern remains about flights over land and populated areas. This is the case where hazards can exist to those below.
All said and done, it’s no time to become alarmed. It may well be the case that these unidentified flying objects were previously ignored. Only now has the militaries in North America been galvanised into action and being more vigilant. The more people look, the more people see.
What do I know? Spy balloon, craft and drones may be much more common than has been generally reported.
Claims and counter claims that everyone is doing it shouldn’t be dismissed out of hand. The technology involved in flying above normal air traffic has a multitude of potential applications. A framework for higher altitude operations is now being written.
POST: Diplomatic tensions between the US and China continue to escalate as the US explains its shooting down of high altitude flying objects over North America. Much is still to be uncovered.
 A Hungarian American physicist and engineer who was born 11 May 1881.