Abiogenic synthesis on Mars.

Atmospheres capable of producing organic compounds under primitive conditions are discussed in the light of recent experimental evidence. The atmosphere of Mars is discussed, in particular, the observations of Sinton of reflection spectra with features at 3.45, 3.58, and 3.69, which are attributes to C-H bands and the presence of organic molecules. Colthup interprets these features as being representative of organic aldehydes and suggests specifically, acetaldehyde. Many works have considered these observations as being indicative of life on Mars. Rea has offered alternative hypotheses. This paper presents experimental evidence of yet another possible explanation; that organic compounds are being produced in the Martian atmosphere, and may be responsible for Sinton's observations. The influence of such syntheses on possible Martian organisms is discussed. Various possible Martian atmospheres have been irradiated with ultraviolet light as well as other possible energy sources and a variety of organic end products have been identified. Martian atmospheres plus acetaldehyde as a starting point have also been used and end products analyzed. Possible abiogenic pathways for Mars are discussed.