[SimbaOnSteroids]

My favorite type of mass hallucination is the type that gets painted by radar.

[jjoonathan]

A third of all radar jammers operate on the principle of generating fake returns that "fly away" (often in unphysical ways because that was good enough).

It's funny how this 101-level fact that every radar technician, operator, and designer is keenly aware of somehow never seems to make it into the UFOlogist monologues about how infallible radar evidence is.

[SimbaOnSteroids]

Yes, and OP said they represented a mass hallucination. Which they're clearly not entirely.

I find it odd that every time this subject comes up people just bend over backwards to behave in the most smug ways possible.

[simonh]

Except that many of them are purely optical phenomena that don’t show up on radar at all. Which of course is even more mysterious and meaningful!