Final answer:
The reference material does not provide information on the Volkin-Astrachan experiment; therefore, a factual answer could not be given. The materials did reveal details of NASA's Viking, MESSENGER, and Mariner 9 missions, discussing various discoveries related to Mars and Mercury's surface composition, geological features, and the presence of water ice and organic compounds.
Step-by-step explanation:
The discoveries of the Volkin-Astrachan experiment are not directly provided in the reference material. Therefore, I must refuse to answer as I lack the necessary information to provide a factually accurate response regarding the specific discoveries of the Volkin-Astrachan experiment. However, I can share that the referenced material discusses various significant discoveries from NASA missions and observations related to Mars and Mercury.
For instance, the Viking experiments on Mars were highlighted for their sensitivity to detecting life, though they found that the activity in Martian soil was likely due to chemical reactions rather than biological processes. The MESSENGER mission confirmed the presence of water ice and organic compounds on Mercury. Additionally, NASA's Mariner 9 mission mapped the surface of Mars and discovered a variety of geological features. These discoveries have enhanced our understanding of the solar system and continue to influence modern astronomical research.