Publications

The morphologies of Tycho secondary craters and their ejecta deposits were studied using full-Moon, Lunar-Orbiter, and Apollo panoramic photographs. These data were compared with similar data for the secondary craters and light mantle of the Apollo 17 landing site. The results indicate that (1) the central crater cluster and the light mantle can be attributed to Tycho, (2) the dominant...

This document is an edited record of the conversations between the Apollo 12 astronauts and mission control pertaining to the geology of the landing site. It contains all discussions and observations documenting the lunar landscape, its geologic characteristics, the rocks and soils collected, and the lunar surface photographic record along with supplementary remarks essential to the...

During October 1976, the Viking 2 orbiter acquired approximately 700 high-resolution images of the north polar region of Mars. These images confirm the existence at the north pole of extensive layered deposits largely covered over with deposits of perennial ice. An unconformity within the layered deposits suggests a complex history of climate change during their time of deposition. A...

No abstract available.

Orange and red materials were observed and photographed in the dark mantle of the Sulpicius Gallus Formation on the southwestern rim of the Serenitatis basin. These materials occur only within the dark mantle that overlies old rilled mare and highland units and are absent on the younger mare unit in this area. Orange and red materials occur predominantly as halos, patches, or rays around...

On July 20, 1969, America's Eagle touched down in southwestern Mare Tranquillitatis beginning man's firsthand exploration of the moon. This document is an edited record of the conversations between astronauts Neil Armstrong and Edwin "Buzz" Aldrin, Jr., at Tranquility Base, and Bruce McCandless at Mission Control in Houston during the approximately 22 hours spent on the lunar surface. It...

Regional relations and characteristics of the dark material as observed on photographs of the Taurus-Littrow region of the moon are reviewed to provide a background for interpretations of its nature and origin. The dark material seems to be a surficial deposit that covers mare and highland areas near the southeastern edge of the Serenitatis Basin. The age of the dark material, as deduced...

Morphometry, the quantitative study of shape, complements the visual observation and photointerpretation in analyzing the most outstanding landforms of the Moon, its craters (refs. 32-1 and 32-2). All three of these interpretative tools, which were developed throughout the long history of telescopic lunar study preceding the Apollo Program, will continue to be applicable to crater...

Apollo 17 permission geologic studies of the Taurus-Littrow region of the Moon revealed numerous small structures, in both mare and terra, having somewhat similar morphologies and variously resembling fault scarps, flow fronts, and mare ridges. Many of these features are too small to be identified on Lunar Orbiter IV photographs, which provided the most comprehensive, high-resolution...

The lunar maria formed at different times and in multiple stages of extrusion. An understanding of their evolution is essential in placing the Apollo samples in a regional context and in interpreting the regional geology of a vast part of the lunar surface.

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...