Just a quick thought about Gospels and their place in the world history...
If you think about it, Genesis 6:1-4 says that God (Yahuah) has sons. Not just one. Many sons.
So the events about one of the sons of God that are recorded in the Gospels is nothing but direct proof of extraterrestrial life.
Why do you think that an alien has to be some 8 legged, 5 eyed creature??? This is a very wrong assumption.
If anything, aliens have human form, because this is what evolution came up with. I do not think that life has evolved in something better than human form.
At the same time, the main character of the Gospels is described to have supernatural powers (which is consistent with Genesis account), so this is what we essentially encountered - a super human - a son of God.
Therefore, imho, if you are looking for proof of extraterrestrial life, look right in front of you - in the Gospels.
Please note that the rest of New Testament was written later, so it does not have the same degree of accuracy as the Gospels. So if you are Christian, you should follow only the Gospels, just like Jews should only follow Torah of the TaNaKh.