Apollo 11 Solar Wind Composition Experiment: First Results

Science  19 Dec 1969:
Vol. 166, Issue 3912, pp. 1502-1503
DOI: 10.1126/science.166.3912.1502


The helium-4 solar wind flux during the Apollo 11 lunar surface excursion was (6.3 ± 1.2) x 106 atoms per square centimeter per second. The solar wind direction and energy are essentially not perturbed by the moon. Evidence for a lunar solar wind albedo was found.