Titan's atmosphere could give life clues

TUCSON, June 30 (UPI) -- U.S. scientists say they've shown how the atmosphere of Jupiter's moon Titan, similar to that of pre-life Earth, may have created molecules necessary for life.

University of Arizona researchers say sunlight striking Titan's methane- and nitrogen-rich atmosphere could create organic macromolecules that could form the basis of biological systems, a university release said Wednesday.

In an experiment to mimic how solar radiation affects Titan's atmosphere, university researchers Hiroshi Imanaka and Mark Smith converted a nitrogen-methane gas mixture into a collection of nitrogen-containing organic molecules by irradiating the gas with high-energy ultraviolet rays, the release said.

Imanaka and Smith say they believe such compounds are formed in Titan's upper atmosphere and eventually fall to Titan's surface. Once on the surface, they could contribute to an environment that is conducive to the evolution of life, they said.

"Titan is so interesting because its nitrogen-dominated atmosphere and organic chemistry might give us a clue to the origin of life on our Earth," said Imanaka. "Nitrogen is an essential element of life."