“And war broke out in heaven: Michael and his angels battled with the dragon, and the dragon and its angels battled 8 but it did not prevail, neither was a place found for them any longer in heaven. 9 So down the great dragon was hurled, the original serpent, the one called Devil and Satan, who is misleading the entire inhabited earth; he was hurled down to the earth, and his angels were hurled down with him. 10 And I heard a loud voice in heaven say: “Now have come to pass the salvation and the power and the kingdom of our God and the authority of his Christ, because the accuser of our brothers has been hurled down, who accuses them day and night before our God! 11 And they conquered him because of the blood of the Lamb and because of the word of their witnessing, and they did not love their souls even in the face of death. 12 On this account be glad, you heavens and you who reside in them! Woe for the earth and for the sea, because the Devil has come down to you, having great anger, knowing he has a short period of time.” Revelation 12
“Afterward it came to be the day when the sons of the [true] God entered to take their station before Jehovah, and Satan also proceeded to enter right among them to take his station before Jehovah. 2 Then Jehovah said to Satan: “Just where do you come from?” At that Satan answered Jehovah and said: “From roving about in the earth and from walking about in it. Job 2
“Now it came about that when men started to grow in numbers on the surface of the ground and daughters were born to them, 2 then the sons of the [true] God began to notice the daughters of men, that they were good-looking; and they went taking wives for themselves, namely, all whom they chose. 3 After that Jehovah said: “My spirit shall not act toward man indefinitely in that he is also flesh. Accordingly his days shall amount to a hundred and twenty years. 4 The Nepilim proved to be in the earth in those days, and also after that, when the sons of the [true] God continued to have relations with the daughters of men and they bore sons to them, they were the mighty ones who were of old, the men of fame.”Genesis 6
Long ago the scriptures told us about angels coming down from heaven, some took women as wives and had children by them. The scriptures refer to them as disobedient angels, humans call the aliens. They are here, they have always been here, from the garden of Eden to this very day.