There are ancient maps showing Antarctica without ice. There are many of these maps from different sources.
There has been plenty of time in Earth's history for intelligent species to develop ,disappear, and develop again. We may not be the first, even though our ego insists that we are.
The library of Alexandria held information from all over the world, and we do not know what was lost in the fire that destroyed it.
A ship was not allowed to port in Alexandria unless they had a book or a map to give to the library, and ships came from all over the world.
Was this a deliberate arson to set back technology for thousands of years, or just a random event?
Some societies resist progress for fear of losing power.
People were executed for challenging the current beliefs.
Perhaps there was a technology that advanced far beyond our current capabilities,
or a technology that enabled them to leave the Earth and travel the galaxies; Perhaps even travel through time.
Maybe the UFO's we see are from ancient(future) technologies checking up on our progress. Or perhaps tourist on a site seeing trip, like us visiting a zoo.
IF time travel will ever be possible, then it is possible that we may have visitors from any time period. "SPOOKY?"
Let go of ego, and think outside of the galaxy, outside of today's societal limits of possibilities and wander the infinite possibilities of imagination.
Imagination can travel faster than C, to the far reaches of another dimension without delay.
Paranoid? Sure, maybe. But a little paranoia opens the mind to new possibilities so a little is healthy.
As the old saying goes" A Little poison is physic."(Not physics--it is an old term for medicine
)I am an "Old Phart" after all.
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