https://nypost.com/2023/02/16/ufo-shot-down-by-400k-us-missile-may-have-been-a-12-hobby-balloon/
(原文相当长,翻译费事费时,大意是很可能只是一个学校用作教育的$12 气球,上面带了ham radio 可以追踪的a small GPS transmitter and an antenna)