Unidentified objects: What's behind the rise in aerial shootdowns?
https://www.newscientist.com/article/2359263-unidentified-objects-whats-behind-the-rise-in-aerial-shootdowns/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home
Unidentified objects: What's behind the rise in aerial shootdowns?