Publications

Mare Serenitatis is a circular mare approximately 600 km in diameter in the northeast quadrant of the lunar near side. It occupies an old multi-ringed basin (refs. 33-1 and 33-2) and is the site of a prominent mascon (ref. 33-3). A conspicuous dark annulus in this mare prompted subdivision of the mare materials into different stratigraphic units (refs. 33-2 and 33-4). A revised...

Stereoscopic photographs of the Moon taken by the metric and panoramic cameras on board the service module of Apollo spacecraft provide a source for quantitative data on lunar topography. The accuracy of the topographic data depends, in part, on the repeatability of elevation measurements. The repeatability depends on contrast in the stereoscopic image and is affected by many factors...

The lunar surface orientations of some of the Apollo 17 rock samples at the time of their collection (table 6-V) are shown in this appendix (figs. 6-65 to 6-87). These orientations were determined by correlating lunar photographs of samples before collection with shapes and shadow characteristics of the same samples in the LRL under oblique illumination with nearly collimated light. The...

Lunar slope-frequency distributions obtained by photogrammetric techniques are compared with results from the bistatic-radar investigations of the Apollo 14, 15, and 16 missions (refs. 33-16, 33-17, and 33-32) and of Explorer 35 (ref. 33-27). Algebraic standard deviations of slope-frequency distributions from photogrammetric data are equivalent to rms slopes of slope-frequency...

Small volcanic cones with summit craters or breached walls occur in several areas on the Moon. Most of these features have basal diameters of approximately 1 to 2 km and probably are not more than a few hundred meters in height. None have been so clearly photographed, however, as those shown in Apollo 17 metric and panoramic camera coverage of the southeastern margin of the Serenitatis...

A dark-colored surficial deposit covers lowlands and highlands along the southeastern margin of the Serenitatis basin. Sampling of this material was a major exploration objective of the Apollo 17 mission. Since completion of the mission, the dark mantle has been the subject of considerable controversy, inasmuch as no obvious stratified deposit was found in the landing area. Yet the...

No abstract available.

The scientific objectives of the Apollo lunar sounder experiment (ALSE) are (1) mapping of subsurface electrical conductivity structure to infer geological structure, (2) surface profiling to determine lunar topographic variations, (3) surface imaging, and (4) measuring galactic electromagnetic radiation in the lunar environment. The ALSE was a three-frequency, wide-band, coherent radar...

Stereoscopic photographs taken by the metric and panoramic cameras can be used to obtain information on the roughness and slope-frequency distributions of lunar surfaces (see appendix to this part). Bistatic radar on board Apollo 14, 15, and 16 spacecraft may also be used to obtain information on lunar surface roughness at two wavelengths—13 cm (S-band) and 116 cm (VHF).

Apollo 17 metric photographs (fig. 29-26) provide the best available coverage for geologic interpretation of northern Mare Crisium and the northern Crisium basin. The area was covered previously by low-resolution telescopic and Lunar Orbiter IV photographs and by oblique, high-illumination, or low-resolution photographs from earlier Apollo missions. One region in particular, between...

A large quantity of data on backscattered polarized and depolarized radar echoes from the Moon has been collected from Earth at 3.8-cm wavelength (ref. 33-23). Depolarized echoes are particularly interesting because theory indicates that relatively strong depolarized echoes can be caused by the following factors.

No abstract available.