English: By passing electrical sparks through mixtures of hydrogen, methane, ammonia, and water vapor, scientists produced colored amino acids, the building blocks of organic life. The experiment was first performed by Stanley Miller in 1953 and has now been repeated many times elsewhere. This photograph show an experiment at NASA-Ames Research Center's Chemical Evolution Branch. When methane or acetylene, both constituents of the Jovian atmosphere, is sparked in a chamber together with ammonia at the temperature of liquid nitrogen, reddish-brown polymeric material is synthesized. Such processes might be responsible for the colors of the Jovian atmosphere.