The Heavenly Vortex is a completely different phenomenon from a flying saucer or any other kind of sky chariot. It is a
funnel going back into the (presumably hemispherical) surface of the sky, connecting our realm to somewhere else. If it sometimes appears tilted, that is because the artist is trying to convey a hole in a hemispherical surface, so it would naturally appear tilted from the side.
If people use ancient iconography to back up the ET hypothesis, they need to understand what the original images depicted. The Heavenly Vortex is a fascinating attempt to depict multiply-connected space, on a par with Deep Space Nine for instance. Medieval SFX.
It is not a flying saucer.
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