Are aliens angels, or are they the fallen angels? Is it possible that the fallen angels went underground during the flood? If not, how is it that there are fallen angels still to this day if the flood wiped all of them out?
The Bible teaches that life only exists on the Earth, for the rest of the universe was created solely for humanity to witness. All life that exists is present on the Earth, so “aliens” do not exist.
Therefore, the various supposed sightings of aliens must be either lies, hoaxes, atmospheric phenomenon or the deceptions of demons. Demons are fallen angels, and the Bible says they sometimes present themselves to men as “light” (2Cor 11:14). Therefore, it’s possible that some of these appearances are demons working to convince humanity that life exists elsewhere in the Universe.
Regarding the flood, no demons (or angels) were destroyed in the flood. Only those who dwell on the earth were destroyed. The victims included the Nephilim, the offspring of the demons and women (see our teaching from Genesis 6 in our Genesis Bible study). After this, the Lord also placed the demons responsible for this perversion into the abyss:
Jude 6 "And angels who did not keep their own domain, but abandoned their proper abode, He has kept in eternal bonds under darkness for the judgment of the great day,"
So although some of the demons are in a prison, the rest are still roaming free under the control of Satan.