What is known about the mysterious objects that were shot down over North America?

(CNN) ⸻ An unidentified object was shot down over northern Canada on Saturday, marking the third time in a week that US fighter jets have taken down objects in North American airspace. The object was detected by North American Aerospace Defense Command (NORAD) and two F-22 fighter jets from Joint Base Elemendorf-Richardson, Alaska, were sent up to monitor the object with the help of the Alaska Air National Guard. The object appears to be a "cylindrical object" smaller than the Chinese surveillance balloon that was shot down previously, and was shot down with a AIM-9X missile from a US F-22. The FBI and Royal Canadian Mounted Police are working together to recover an unidentified object shot down by a US F-22 over Alaskan airspace on Saturday. The object was flying at 40,000 feet, making it a risk to civilian traffic. This is the third such incident in one week, following the Chinese surveillance balloon shot down off the coast of South Carolina last Saturday. The US military is still working to recover debris from the balloon on the ocean floor.