One might recall that during the 1910-1950 period, 'scientists', including 'sophisticated' fiction writers, determined by consensus, not proof, that life existed on Mars. A similar group of 'experts' propounded during the 1940-1960 period [before the Voyager space probes] that Venus' atmosphere was similar to the Earth's, and that quite likely there was life. In actual fact Venus' surface temperature is 1000 F raising the rather obvious objection that the planet may be new and has not yet cooled down [though the 'consensus' blames a greenhouse effect]; and Mars is dead cold unsuitable for complex life [though the Hollywood scientists continue to show Mars as a red-hot desert].
The million to million ratios and variables which allow life on Earth, do not, and will not be found anywhere else. From the exact weight of a proton in relation to the nucleus and neutron [without this precision there is no life]; to the fact that the gas giants Jupiter and Saturn protect the Earth from cosmological debris and asteroids and also maintain the Earth's near perfect circular orbit around the Sun [it varies by 2%, if you moved Saturn for example, further in or out from its existing orbit the Earth would not orbit in the habitable zone around the Sun]; we can see that the 'fine-tuning' for life is not an accident.
The Search for Extra-Terrestrial Life is of course a materialist-naturalist preoccupation with their theology that humans are apes, the Earth nothing special, our Sun just an average star, and our galaxy some trash hole at the fringe of the cosmos. If another planet would but yield complex life than surely that would disprove 'God'. Of course it would not. And the chances of finding any life whatsoever anywhere is less than zero. Mathematical laws of probability make ET life nothing more than absurd fiction – like evolution.
But the cult of science marches on – with their materialist theology. In the 19th century the 'consensus' was that surely life existed since there were 'billions of stars and planets' and that by 'accident' new forms of complexity would arise. For 150 years there has been a search for ET and none has been found. None will be. The ratio's involved in producing life are so magnificently irreproducible, that you would have more of a chance of finding a particular atom in our universe, from the 10 to the power of 80 which exist.
The theology which drives the cult of science is not much interested in physical facts or mathematical statistics. It never has been. The dogma is important. In the 19th century the list of 'scientists' who told their readers that life existed elsewhere was obscenely long. Indeed these worthies cried that life existed on the moon, Venus, Mars, Jupiter, the Sun, and Mercury. 'Solarians' apparently had 'adapted' their almost formless bodies to withstand the intense heat of the Sun. Those who believed that life existed on nearby planets and the Sun included:
-Sir William Hamilton [1805-1856]
-Sir Humphry Davy [1778-1829]
-Sir David Brewster [1781-1868]
-Francois Arago [1786-1853]
-Hans Oersted [1777-1851]
-Richard Owen [1804-72]
-J. Lockyer [1836-1920]
-Jean Liagre [1815-1892]
-Jules Jansen [1824-1907]
-William Pickering [1858-1938]
....you could add about 50 more names of the great and good, the 'experts' who 'knew'. Francois Plisson a doctor and critic of the space-people cult, wrote in 1847, 'Almost all the astronomers of our day, and the most eminent among them, freely adopt the opinions that not long ago were viewed as being able to spring only from the mind of a madman.'
Not much science here. The evidence, the probability, common-sense, natural laws and ratios would lead to the conclusion that life is Earth-bound. The cult of science however, has a nasty predisposition to interject fiction into the process of science and declare the resulting admixture as factual. Appeals to authority or those with advanced degrees, or to someone who 'knows about such things', does not mean that their observations are either true or scientific.