Erich von Daniken wrote a book, "Chariots of the Gods" which led to a culture of Danikenitis mainly within American university and college campuses, from early to mid 1970s. Daniken wrote that our planet was visited by aliens, or space gods, about 40,000 years ago, who tinkered with the genes of early ape men to produce the present Homo Sapien species of today. They were also involved with the construction of the Great Pyramid of Egypt, the statues of Easter Island, the line drawings on the plains of Nazca, and even proposed that in the Bible, the Tabernacle Moses had built was a radio communication unit and the strange visions Ezekiel had was that of a helicopter.
Early inhabitants of the earth, according to Daniken, worshipped these visitors as gods, because of their technology.
Every mainstream scientist and archaeologist at best refuted all of Daniken's theories, or at worst, just ignored them. One of the scientists who refuted Daniken was Carl Sagan, who I believe, set up SETI in search of possible life elswhere in the Universe.
Author Arthur C. Clarke, who wrote "The Sentinel" which later became the basis for the movie "2001 A Space Odyssey" which was a movie about our planet being visited by a super race of space gods, who evolved out of their bodies to exist as pure energy. Clarke also rebuked the works of Daniken.
If there is life "out there" then evolution is a true science. For if we have evolved, then there is no reason why evolution is not at work elsewhere.
If we are created, as the Bible says we are, then God must have created life on other planets too. On top of this, Christ would have to die on that planet to atone for their sins as well. This would contradict what the Bible says that Christ died once for all time, to reconcile us to God once and for all.
Going by what the scientists and writers say, as well as what the Bible says, there can't be any other life in the Universe. We are alone.