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Volume 9: Number 3: Article 6

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Could Extraterrestrial Intelligences be Expected to Breathe Our Air?

Michael D. Swords, Dept. of Science Studies, Western Michigan University, Kalamazoo, MI 49008

An objection sometimes raised to the Extraterrestrial Hypothesis (ETH) in UFOlogy, especially as it is applied to Close Encounters of the Third and Fourth Kinds (cases wherein UFO occupants appear), is that beings from other worlds could not find our own atmosphere compatible. Therefore all such reports are a priori false. This paper goes beyond that simple "common sense" position to analyze whether it is scientifically defensible. It concludes that this anti-ETH position is not only indefensible but that reasonably strong arguments can be made that atmospheric compatibility might be the rule rather than the exception. Information is drawn from astronomy, planetology, biology and the history of technology.