A program of unmanned space missions designed for planetary exploration. There were a number of such missions in the program, but the most notable were Pioneer 10 and Pioneer 11, which explored the outer planets and left the solar system. Both carry a golden plaque (see Pioneer plaque), depicting a man and a woman and information about the origin and the creators of the probes, should any Extraterrestrials find them someday.
... the water molecules which are consumed in the reaction. This was first proposed in the 1930s by C. B. van Neil of Stanford University, while investigating photosynthetic ...