They are either military technology, unrecognized natural phenomena or just spurious reports. It seems impossibly unlikely that any alien artifact has ever been near earth.,
Quite possibly.
But it would be narrow-minded not to include the category that the DOD and many others have also included, "other."
So far, no one investigating these reports (recorded by various sensors employing the latest technology as well as sightings by pilots) has reached a conclusion.
That said, Navy pilots have said that whatever these things are (and I certainly don't know), they are solid and they are interfering daily with our training missions in ways that will possibly lead to loss of aircraft and/or loss of life.
Yep, all these supposed sightings and crashes and not so much as single verified alien nut or bolt.
But we’ve got hardware spread from one end of the solar system to the other.
They are either military technology, unrecognized natural phenomena or just spurious reports. It seems impossibly unlikely that any alien artifact has ever been near earth.
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Foreign tech going back at least to the Middle Ages and even photographed in the late 1800s over New England from a hot air balloon.
Couldn’t possibly be from a prior Earth civilization(s) for the same reason that they could not be from some distant star/galaxy/dimension: the science is settled and all history is known - just some minor details to fill in, is all.
Or a spiritual — not in a good way — phenomena to pave the way to rationalize the sudden disappearance of millions of Christians “in a twinkling of an eye” some day.