If airplanes existed millenia, their wreckage long be gone because metals often break down over time. That is likely why we rarely find anything that is +10,000 years ago. The Bible is written in a very poetic nature. It is vague because of the authors of the Bible wrote it that way. They are writing in codes.
Just found this Ptar, but who is to say that aliens used physical craft to travel the universe.
Only way I can see for us to go into space is for us humans to never leave home and just send out our unmanned craft to to explore and send information back to us.
Our physical bodies were never designed to go off planet and the oceans on this planet are designed to not allow us to their greatest depths.
So here is Stephen Hawking's now worried about an Aliens encounter.
He cannot believe that aliens have human body's, brains or in any way our physical attributes.
He must be speaking of spores or germs that can harm us.
At one time man had to write in code else the church would burn them at the stake. Before them were the men that simply wrote about what they saw and put their own interruption on it.
Where did men like Pythagoras come from, Socrates, Plato and others of their time that knew about the Atoms that make up our world thousands of years before we ever thought of them.?
The one in a million men that were mathematicians in a world of people that counted on their fingers ?
Why were these men able to see things others did not, how did they come to their conclusions yet later on in history men had to hid the knowledge or perish.?