Exobiological investigations on Russian spacecrafts.

To investigate the possibility of prebiotic synthesis of organic molecules in open space, conditions involved irradiating nucleosides and inorganic phosphate during five Earth-orbiting Russian space missions that included Salut-7 (13- and 16-month missions), Mir, Bion-11, and Cosmos-2044. Dry films of samples were exposed from 2 weeks up to 16 months to the entire set of factors encountered in open space during Earth-orbiting missions. After each mission, products synthesized during flight and any compounds that remained undegraded were analyzed.