Science Experiments -

The Bistatic Radar Experiment was performed on
Apollo 14, 15, and
16. In this experiment, radio waves were transmitted from the Command and Service Modules, bounced off the Moon's surface, and recorded at tracking stations in California. The properties of the waves recorded on Earth were analyzed to determine the roughness of the Moon's surface in the region where the radio beam was reflected. In addition, the electrical properties of the lunar surface (specifically, the dielectric constant of the lunar rocks) were also determined. The region analyzed by this method was about 10 kilometers across, and the spot being studied scanned across the Moon's surface as the spacecraft moved in its orbit.