The Face was not created by aliens because there is no evidence on The Face to be able to test to see if it was created from an alien. We have searched The Face to find out to see if The Face was made by aliens, and the face was not crafted from aliens because we have not seen a single artifact, text, and/or any symbols near this landscape.

Since we have not seen an artifact in the landscape we could tell that there were no aliens near this area. Since we have not seen an artifact, yes, they could have maybe known that they dropped it and culd have gone searching for it, but then what about the other aliens they could have dropped any crafting utensils at the sight.

Now if there were any text in english then the text could have been from a fellow american space travelar, now if it was made by an alien the text wouldn't be in english, but there is no text in the sight because we haven't seen any so therefore it was not made from an alien, now if it were to be made from an alien they would have text or symbols on The Face because they wouldn't just leave it like that and then walk away. They would have put text or symbols.

Talking about symbols there are zero amount of symbols on that artifact because like I said earlier they would have put text or symbols on the artifact, but there are none of those things.

This shows how there was no chance of The Face showing that there were aliens building it.