Worlds in Collision
Tim Callahan, religion editor of "Skeptic", presses the case further in claiming that the composition of the atmosphere of Venus is a complete disproof of "Worlds in Collision". "...Velikovsky's hypothesis stands or falls on Venus having a reducing atmosphere made up mainly of hydrocarbons. In fact, the atmosphere of Venus is made up mainly of carbon dioxide—carbon in its "oxidized" form—along with clouds of sulfuric acid. Therefore, it couldn't have carried such an atmosphere with it out of Jupiter and it couldn't be the source of hydrocarbons to react with oxygen in our atmosphere to produce carbohydrates. Velikovsky's hypothesis is falsified by the carbon dioxide atmosphere of Venus."
Venus Atmospheric Maneuverable Platform
Since some models suggest Venus once had a habitable climate with liquid water on its surface for as long as 2 billion years, it is speculated by some scientists that these absorption features could be caused by large masses of microorganisms suspended in the lower cloud layer, and hypothetically thrive on iron- and sulfur-centered metabolism. On Earth, some extremophile bacteria can thrive in very acidic conditions, can feed on carbon dioxide, and excrete sulfuric acid.