Search for biochemical fossils on earth and non-biological organic molecules on Jupiter,Saturn and Titan

Recognizable remnants of ancient biochemicals may survive under mild/moderate geological environments. Acyclic isoprenoid hydrocarbons, cyclic hydrocarbons with terpenoid carbon skeletons (e.g. hopanes) and vanadyl and nickel porphyrins have been isolated from organic matter, including petroleum, in Phanerozoic sedimentary rocks. Remnants of lignin have also been found. Usually, carbohydrates do not survive long; they degrade and/or react with other organic substances to form macromolecular matter. Proteins, e.g. apparently those in dinosaur bone collagen, break down relatively rapidly. Life arose during the Precambrian and potential biochemical fossils, e.g. n-alkanes, 2,5-dimethylfuran have been isolated from Precambrian kerogens. Traces of hydrocarbons, NH₃, PH₃ occur on Jupiter and Saturn. Hydrocarbons, N₂ and HCN, the latter a key intermediary in the laboratory abiological syntheses of amino acids and nucleic acid bases, are present on Titan where life could not have evolved. Precursor abiological organic molecules of some complexity may have been synthesized on Titan and the Jovian planets.