There are no aliens.

http://www.abc.net.au/news/2016-01-27/parkes-astronomists-unfazed-aliens-could-already-be-extinct/7116256

Here is a news article trying to explain away the fact that why we have not found aliens yet. Firstly, the reason people think there should be aliens is that there are so many stars in the universe. Because there is so many, there must be some which have planets, and among those planets there must be some that can have live, and among those planets with life, there must be some that have intelligent life like us humans. The argument is simply because there is really so so so many stars, even if the other conditions are just a fraction, then that fraction is still big enough for there to be intelligent life out there.

The Word of God that we have received from Moses up until the Revelation of Jesus Christ recorded by John, only talks about The Almighty God and his relationship with us humans, and also intelligent spiritual beings such as angels and fallen angels. There is no mention of other physical intelligent beings. One can argue that that does not rule out extra-terrestrial intelligent life forms, but simply that God does not need us to have contact even if He had also created them. This is plausible, but our speculation would not give any concrete answer, only God can answer that question.

Coming back down to earth, the fact is that we have not found any intelligent aliens. Aliens are not in God's plans otherwise He would have told us about it. We should do well in attending to the things emphasised by God through His Word and focussing on how we can serve Him here on Earth. 

Update 1 Feb 2021

https://www.quora.com/Are-there-any-UFO-incidents-that-were-genuinely-disturbing-and-frightening-and-cant-be-explained

Various people contributed to the post above to recount UFO-related events all over the world. The description of these events defy natural explanations as well as multiple eyewitness accounts that cannot be dismissed easily.

An American Lama in Philadelphia

There are all kinds and manner of belief. It may be worth looking deeply into them to see what is the core of those belief. Because in the end they are either false or true and there is no in between. The article below reveals one aspect of the believe of a popular world religion. Then compare with what the Word of God says about these in 2 Peter 2.
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http://www.time.com/time/world/article/0,8599,2111552-1,00.html
All-American Lama: How an 11th Century Mystic Was Reborn in Philadelphia

"As a 5-year-old, Erdne Ombadykow began to display signs of eccentric behavior. While his many brothers and sisters were busy watching cartoons on TV or playing in the streets of their rough Philadelphia neighborhood, Erdne would bug his mother to take him to a nearby Buddhist temple.
At the temple, the moonfaced little boy would mimic the chanting monks. Erdne's parents were Buddhists — they were immigrants from Kalmykia, a Mongolian enclave inside Russia — but not particularly religious, and they were baffled by their son's devotion. In 1979, when Erdne was 7, the Dalai Lama visited the temple, and the little boy crawled straight into his lap."
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2 Peter 2
1 But there were also false prophets among the people, even as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Lord who bought them, and bring on themselves swift destruction.