Aliens in the Quran
The holy Quran clearly says the existence of extraterrestrial life spreading throughout the universe.
[42:29] Among God’s proofs is the creation of the heavens and the earth, and the living beings He spreads in them. He is able to summon them, when He wills.
God in the Quran clearly mentions there are countless earths in the universe. It seems the verse [65:12] talks about seven earths like seven universes but it is just an allegory to tell this unbelievable fact to the ancient people nearly 1500 years ago. It actually means that there are numerous earths or earth-like planets in the universe.
[65:12] GOD created seven universes and of the earth the like of them. The commands flow among them. This is to let you know that GOD is Omnipotent, and that GOD is fully aware of all things.
The Quran clearly says not only the existence of extraterrestrial life throughout the universe but also informs the nature of extraterrestrial beings! The verses [55.33-35] are profound because they clearly say that we cannot cross the boundary of space after certain point without authorization. Like crossing from one country to another, one needs visa; it is clear that we also need to have visa once we go beyond certain point in space beyond the earth.
Aliens
It implies that the other intelligent creatures like us are occupying there, so we cannot reach there without their permission. This also suggests that there are many intelligent civilizations in the universes and some of them are technologically so advanced that they can stop our journey by firing something which we cannot withstand! So those advanced intelligent civilizations already secured their space borders firmly when the Quran was revealed around 1500 years ago.
[55.33] O assembly of the jinn and the men! If you are able to pass through the regions of the heavens and the earth, then pass through; you cannot pass through but with authority.
[55.34] Which then of the bounties of your Lord will you deny?
[55.35] The flames of fire and smoke will be sent on you two, then you will not be able to defend yourselves.
Irony is that still our space border is not secured enough and aliens are entering the earth without our authorization! So many people around the globe are seeing alien spacecraft almost on daily basis but many people are still not sure what the hell is happening secretly! Anyway, yes, Muhammad was indeed a messenger of God.