Well yes they discared aliens in the past , but now that we have airplanes , and technology , now when you read the events of moses and the like , we can see that he could have been experiencing another technologically advanced civilization , take the passage where the 10 commandments are "handed" to him. Of course , before we had technology , all of this was interpreted divinely , we had no electricity , we didnt have lightbulbs , no cars , airplanes , so aliens would have been out of the question. Today's advancement allows us to interpret the scripture differently , but it still doesnt discard it or it's authenticity , it merely restates the fact that something very strange happened during the time our civilizations came to being.

"That is a faulty assumption and doesn't belong here."
No faulty assumption , look at the genome project , it is estimated the dna mutated around 3000 years bce , affecting the pigment , thus brining white people , but why would this mutation stay prevalent ? well i'm in a rush , i'll write more on this later.