Apollo 11 Laser Ranging Retro-Reflector: Initial Measurements from the McDonald Observatory
- 23 January 1970
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 167 (3917) , 368-370
- https://doi.org/10.1126/science.167.3917.368
Abstract
Acquisition measurements of the round-trip travel time of light, from the McDonald Observatory to the Laser Ranging Retro-Reflector deployed on the moon by the Apollo 11 astronauts, were made on 20 August and on 3, 4, and 22 September 1969. The uncertainty in the round-trip travel time was ± 15 nanoseconds, with the pulsed ruby laser and timing system used for the acquisition. The uncertainty in later measurements of a planned long-term sequence from this observatory is expected to be an order of magnitude smaller. The successful performance of the retro-reflector at several angles of solar illumination, as well as during and after a lunar night, confirms the prediction of thermal design analyses.Keywords
This publication has 3 references indexed in Scilit:
- An Inexpensive Multichannel Scaler with Channel Widths of Less Than 1 μsecReview of Scientific Instruments, 1969
- Implications for Geophysics of the Precise Measurement of the Earth's RotationScience, 1967
- Optical radar using a corner reflector on the MoonJournal of Geophysical Research, 1965