Apollo 11 Laser Ranging Retro-Reflector: Initial Measurements from the McDonald Observatory.
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.
Alley
C O
CO
Chang
R F
RF
Curri
D G
DG
Mullendore
J
J
Poultney
S K
SK
Rayner
J D
JD
Silverberg
E C
EC
Steggerda
C A
CA
Plotkin
H H
HH
Williams
W
W
Warner
B
B
Richardson
H
H
Bopp
B
B