The findings suggest the building blocks of life on Earth may have originated in the air, not only in primordial "soup" on land.

Based on lab experiments, scientists concluded it's possible the thick atmospheric haze on Titan contains the five so-called nucleotide bases used in DNA and RNA, as well as some simple amino acids—the building blocks of proteins. (See a quick guide to DNA.)

That's not to say Titan is any more likely to host birds, fish, or even microbes like those on Earth, emphasized study co-author Sarah Hörst, a graduate student at the University of Arizona's Lunar and Planetary Laboratory.

"If there's life on