After deploying the Rover and prior to traversing to the ALSEP site, the right rear fender extension of the fender was inadvertently pulled off. The fender extension was secured with tape. The ALSEP and the Cosmic Ray experiment were deployed (figure 86). Steno Crater was sampled in lieu of the

pre-planned station (Emory Crater). The new station was selected because of accumulated delay time in completing preparations for the traverse. During the traverse the fender extension came off and, as a result, the crew experienced a great deal of dust. The Surface Electrical Properties (SEP) Transmitter was deployed near the end of the EVA. The 0.23 kg (1⁄2 lb.) and 0.45 (1 lb.) explosive packages (EPs) were deployed and tidal gravimeter readings were made at select locations. Duration of EVA-1 was 7 hours, 12 minutes.

On December 12, 1972, prior to starting EVA-2, the crew received instructions from the ground controllers for improvising a replacement for the lost fender extension. Four maps, taped together and held in position by two clamps from portable utility lights, made an excellent substitute for the extension and the crew did not experience the dust problem as on EVA-1.

All preplanned stations were visited although station times were modified to accommodate changing priorities. A brief stop at the South Massif was made to obtain Traverse Gravimeter readings and additional samples (figure 87). During this traverse, the crew deployed the 0.06 Kg (1⁄2 lb.), 2.7 Kg (6 lb.) and 0.11 Kg (4 lb.) explosive packages, obtained photographs, and documented samples. EVA-3 was initiated on December 13, 1972, and was terminated 7 hours and 15 minutes later. Exploration of the stations was modified during the traverse to permit the crew a longer stay time on the North Massif and to explore unusual landforms called the Sculptured Hills. Photographs and documented samples were obtained at all stations. About 66 Kg (145 lbs.) of samples were retrieved, and the LRV traversed a total of 11.6 Km (6 nm).

The 1.4 Kg (3 lbs.) explosive package, left over from EVA-1 was deployed in addition to the 0.11 Kg (14 lb.) and 0.06 Kg (% lb.) packages.

The total time for the three EVAS was 22 hours, 5 minutes, 4 seconds. The total distance traveled in the lunar rover was about 35 km. The combined weight of samples was about 116 Kg (255 lbs.) plus 2 double cores and 1 deep drill core. Surface photographs taken during the three EVAS total at least 2389. Good quality television transmission was received throughout the mission. Ascent on December 14, 1972, rendezvous, docking, LM ascent stage impact on the lunar surface, transearth injection, coast, reentry, landing and astronaut recovery on December 19, 1972 were all nominal.

Total mission time was 301 hours, 51 minutes.

Surface science

The Apollo 17 site was the first site selected largely in response to new knowl edge acquired on earlier missions. Similarly, the scientific instruments placed on the lunar surface and those used on the traverses and in orbit were designed predominantly to obtain data useful in solving problems whose existence could not be predicted in detail prior to the first several Apollo flights. The sampling objectives were likewise well defined: (1) to sample some of the youngest lunar material to determine whether lunar volcanism ceased 3 billion years ago; (2) to sample for the presence of volatiles; and (3) to sample highland material which may have formed between 4 and 42 billion years ago, a time for which the history of the Earth has been erased. In these objectives, the mission was quite successful.

The instruments included in the ALSEP have already provided some concrete preliminary data concerning the heat flow from the interior of the Moon and the character of the near lunar surface formations. Results from the Heat Flow Experiment (figure 88) (see p. 374) confirms the high value found at Apollo 15 and that the heat flow is not an anomaly. Eight explosive charges were detonated as part of the Lunar Seismic Profiling Experiment (figure 89) (see p. 374). An analysis of the seismic velocity data suggested a layered consolidated material underlying the site. Difficulties were experienced in the initial turn on and calibration of the Lunar Surface Gravimeter and performance in its present operational mode is still under analysis by the Principal Investigator. At this time he feels he will be able to recover a high percentage of the planned seismic, free mode, and tidal data—thus fullfilling most of the major objectives of the experiment. How

ever, this will be verified by analysis of data during the next 3 months. The other ALSEP instruments, the Mass Spectrometer (to study the lunar atmosphere) and the Meteoroid Detector (to study particle impacts of the Moon) are functioning normally.

Two traverse experiments were employed by the astronauts. The Surface Electrical Properties Experiment, employing an electromagnetic subsurface exploration technique, has confirmed the dielectric constant of subsurface rocks also detected from lunar orbit and the data have suggested a subsurface interface approximately 100 meters deep. The Traverse Gravimeter experiment obtained data indicating that layered igneous rocks, similar to those sampled on the traverses, probably extend to depths of at least a kilometer.

The crew visited, observed, photographed, and sampled each of the diverse, major geologic features of the Taurus-Littrow area. The remarkable performance of the crew thoroughly exploited the potential of the landing site and met the highest standards for scientific exploration. Samples obtained on the Massif's could include the oldest materials returned from the moon. The discovery of bright orange material lends credence to suggestions that the area may contain relatively young volcanic features (figure 90). The material appears to be

a finely structured glass of volcanic origin. Samples obtained from this site may include ejecta not only from Serenitatis but also from Tranquillitatis, Crisium, Fecunditatis and Imbrium basins.

Orbital science

All of the major objectives of the Apollo 17 science were successfully achieved. The scientific payload consisted of an Infrared Scanning Radiometer, Radar Sounder, a Far Ultraviolet Spectrometer and the camera and laser system also flown on the Apollo 15 and 16 missions. Doppler tracking of the Command and Service Module S-Band transponder provided lunar gravity data.

Operation of the radar (figure 91) (see p. 376) sounder, a device designed to acquire imagery of both surface and subsurface lunar structure up to 1.3 km, functioned nominally throughout the mission. The radar sounder data are recorded on film which is being processed and analyzed. However, preliminary analysis of telemetry data has revealed that the lunar highlands and mare show distinctively different reflected power signals. The signals indicate the presence of mare subsurface structure while the highlands indicate a lack of subsurface structures.

92-229 (Pt. DO 7325

The Infrared Scanning Radiometer thermally mapped over one-third of the lunar surface to an accuracy of 1 degree. Temperatures as low as 86° K (-306°F) were observed just prior to lunar sunrise and temperatures as high as 400°K (261°F) were observed at lunar noon. The Far Ultraviolet Spectrometer was designed to detect elements of the lunar atmospheric composition and determine their density. Preliminary analyses of the data indicate that the Moon is not degassing and that it does not, on itself, create an atmosphere.

The camera system comprised of panoramic, a mapping and stellar camera, and a laser altimeter, obtained photography of the lunar surface for geological interpretation and for the production of a lunar control system for accurate mapping. A total of 1603 frames of high resolution (approximately 2 meter resolution) panoramic photography and 3554 frames of precision, medium resolution (approximately 20 meters resolution) mapping photography were obtained. The laser altimeter supporting the mapping camera system also provided about six complete revolutions of lunar global altimetery which will significantly aid in understanding the figure of the Moon.

SUMMARY OF MAJOR SCIENCE FACTS AND CONCLUSIONS FROM APOLLO

The Apollo Program has increased our knowledge of the Moon beyond expectation, it has provided new knowledge and techniques for study of both the Earth and Sun, it has led to a wealth of new technology, and has given mankind a new frontier and the beginning of the technology necessary to exploit it. With the conclusion of the Apollo Program, not only do we know much more about the Moon, enabling us to formulate much more meaningful questions about it, but equally important, we know more about the Earth and the solar system as well. The analysis of data from Apollo 17 has just begun. However, based primarily on the results of the previous missions, the following are a few major scientific facts and conclusions about the Moon derived by the Ppollo Program.

1. The Moon is a complex heterogeneous body that has been partly or wholly melted to form mineralogically different layers.

2. We now know that the highlands of the Moon are made up of rocks composed largely of the mineral anorthite. These Calcium-Aluminum rich rocks contrast chemically with the mare basin basalts.