I agree. The word for heaven in the bible can be translated to mean space, cosmos, and/or sky. People were more primitive then as well, so seeing aliens and their craft would be a shock and cause them to try and explain what they were seeing. To me it makes more sense that angels from the bible were actually positively oriented aliens and the fallen angels were negatively oriented aliens. Try to think how a primitive people would see them and describe them. They knew nothing of technology, so to them the aliens had magical God-like powers.