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."
High Altitude Venus Operational Concept
Venus is a planet with a runaway greenhouse effect, with surface temperatures and pressure of and respectively. Conventional rocket engines will not work at those pressures. Hence, human missions to Venus have historically been thought impractical, if not impossible. However, Venus has advantages for crewed travel, such as Earth-like gravity (.90 Earth gravity), an atmosphere that provides a level of protection from solar and interstellar radiation, and a much greater proximity compared to Mars.