Engineering PapersSearch

Engineering topics

Monjes, J. A.

Publications and source records attributed to Monjes, J. A..

Transportable lunar-ranging system.

Description of a transportable transmitting unit for measuring distances to retroreflectors on the moon. The unit can be installed at any astronomical observatory where a large telescope is available to detect the received signal. The transmitter consists of a high radiance, frequency-doubled neodymium-glass laser and a coude optical system of moderate size. The measurements may eventually be used to study variations in the length of the earth's day, changes in the geographic location of the pole, and the drifting of the continents.

Lehr, C. G.

The SAO lunar laser.

The SAO lunar-ranging system is currently being installed at the Agassiz Observatory, Harvard, Massachusetts, USA. It employs a high-radiance neodymium-glass laser and a transmitting telescope whose aperture diameter is only 0.2 m. This telescope is a coude refractor specially built for the purpose, with tracking accuracy 1 second of arc. The receiving instrument is the 1.5-m telescope at the Agassiz Observatory. However, the laser transmitting unit can be moved to other locations where telescopes of similar size are available. Since the large telescope does not transmit the laser radiation, it remains in a normal mode of operation and the regular observing schedule is not disrupted. During routine operation, the receiver field will be larger than that of the transmitter, thus imposing less of a constraint on the tracking capability of the large optical instrument.

Lehr, C. G.