The U.S. has shot several objects out of the sky over the past two weeks. U.S. officials have said they know the most about the first one, which they have described as a Chinese spy balloon outfitted with equipment to collect intelligence and communications.

U.S. officials said these most recent objects did not pose a military threat, but their proximity to sensitive defense sites and the altitude at which they were flying raised concerns and posed a risk to civilian aviation.

U.S. officials said they don’t know who owns the objects, where they came from or what their purpose is. 

Here’s what we do know about the objects.

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