Engineering topics

El-Baz, F.

Publications and source records attributed to El-Baz, F..

48 records · Page 3

NASA NTRS1972

The cinder field of the Taurus Mountains, part I

A dark-colored mare unit within the southwestern corner of the Taurus Mountains is discussed. The geologic characteristics of this unit, the intricate relationship between it and the surrounding features, and the probable source of the unit were the objects of visual observations during the Apollo 15 flight. The results of these observations made from orbit indicate that the unit probably consists of volcanic ash or pyroclastic deposits that came to the surface through a multitude of cinder cones. The local setting of the area and the relationship of the dark deposit to other nearby geologic units are examined in light of data obtained from the Apollo 15 panoramic camera photographs.

El-Baz, F.↗

NASA NTRS1972

Observations and impressions from lunar orbit

On Apollo 16, the command module pilot made observations of particular surface features and processes to complement photographic and other remotely sensed data. Emphasis was placed on geological problems that required the extreme dynamic range and color sensitivities of the human eye; repetitive observations of varying sun angles and viewing directions; and, in some cases, on-the-scene interpretations. Visual observations and impressions recorded during the mission verified the effectiveness of the hardware and techniques used. The orbiting observer functioned both as a sensor, in otherwise inaccessible areas such as earthshine and shadows, and as a designator of potentially significant data that were acquired on the photographic record.

Mattingly, T. K.↗

NASA NTRS1972

Discovery of two lunar features, part H

Study of the Apollo 16 photographs resulted in the discovery of two large features in the far side highlands near the eastern limb of the moon not indicated on existing lunar maps and charts. The larger unnamed feature is a three-ringed 1000 km diameter basin, and the smaller feature is a 200 km diameter crater that is located between the eastern middle and outer rings of this basin. This crater surrounds Becvar Crater. Since these newly discovered features are large enough and significant enough to warrant the assignment of names, the following names have been recommended to the Committee on Nomenclature of the IAU for consideration. Arabia is the name suggested for the newly-found basin to honor Arab contributions to astronomy. Rupes Sibericus (Siberian Scarp) is suggested for the 1 km high scarp that borders the eastern part of the middle ring of the basin. Rupes Apalaches (Appalachian Scarp) was suggested for the 2 km high scarp that borders the western part of the middle ring of the basin. Necho has been suggested for the new found 200 km diameter crater between the eastern middle and outer rings of the basin.

El-Baz, F.↗

NASA NTRS1972

King Crater and its environs, part M

Superb photographs of King Crater were returned by the Apollo 16 crew. The metric and panoramic cameras provided stereoscopic coverage with which high quality topographic maps may be made. King crater, approximately 75 km in diameter and, on the average, 3.8 km deep, is among the most significant features photographed and visually studied from lunar orbit on the Apollo 16 mission. It is the freshest crater on the far side in its size range and has several unique characteristics. (1) Although its ejecta blanket displays very sharp features, the crater does not appear to have extensive ray systems and secondary crater chains. (2) As depicted for the first time by Apollo 16 photographs, the ejecta blanket is strewn with numerous flow fronts and scarps. (3) A flat and smooth, dark, lavalike deposit 15 km across is on the northern rim of the crater. (4) The central peak of the crater is a Y-shaped structure that begins at the southern rim. (5) Bright units that are aligned with the central peak on the northern wall and rim suggest that a preexisting tabular body was excavated by the cratering process.

El-Baz, F.↗

NASA NTRS1972

The Alhazen to Abul Wafa swirl belt: An extensive field of light colored, sinuous markings, part T

Problematic causes and characteristics of light colored sinuous markings on the lunar surface are explored. Two processes, exogenetic and endogenetic, are examined in detailed. During the endogenetic process it is suggested that impact ejecta deposition and surface disturbances cause the markings. During the endogenetic process, it is suggested that extrusive volcanism and sublimation and/or alteration cause the markings.

El-Baz, F.↗

NASA NTRS1972

Significant results from Apollo 14 lunar orbital photography.

Apollo 14 obtained 950 photographs from lunar orbit using the Hasselblad and Hycon cameras. The photographs reveal a number of new geologic features as well as previously unrecognized details of the morphology, structure, and stratigraphy of lunar surface units. The primary result is the verification of the extensive role of volcanism in the formation and modification of the lunar highlands, especially on the far side. Terra volcanism appears to be manifest in the formation of (1) constructional units of hilly and furrowed materials of regional extent as in the Kant Plateau in the central near-side highlands and northwest of the crater Pasteur near the eastern limb of the moon; (2) somewhat viscous lava flows and pools associated with fracture systems and/or what appear to be volcanic craters; (3) craters, crater chains, and irregular depressions, particularly on the lunar far side. The first photographs of a flow channel, a leveed sinuous rille that apparently originated by lava flowage on the surface, were obtained by Apollo 14. Another first is a high-resolution photograph of the interior of what appears to be the youngest lunar crater yet photographed in the 20- 40-km size range.

El-Baz, F.↗

NASA NTRS1972

Astronaut observations from lunar orbit and their geologic significance.

To supplement orbital photography and other remotely sensed data, visual observations were made of 15 lunar surface targets during Apollo mission 15. Among the significant results are (1) characterization of the floor material of Tsiolkovsky as no darker than the average (Eratosthenian) mare material, and interpretration of the lineated unit on the crater rim as a rock avalanche; (2) identification of layers on the wall of the crater Picard, which is probably volcanic in origin, (3) explanation of the ray-excluded zone of the crater Proclus as the result of structurally controlled ray shadowing; (4) observation of cinder cones in the Littrow area with dark haloes that probably are composed of pyroclastic deposits; and (5) recognition that the termini of numerous sinuous rilles in Oceanus Procellarum are flooded with younger mare materials that may have covered older terminal deposits.

El-Baz, F.↗

NASA NTRS1971