Home Table of Contents What's New Image Index Copyright ScienceViews Search


Apollo Expeditions to the Moon

CHAPTER 12.6



THE HUNT FOR THE RIM OF CONE

Another problem was that the ruggedness and unevenness of the terrain made it very hard to navigate by landmarks, which is the way a man on foot gets around. Ed and I had difficulty in agreeing on the way to Cone, just how far we had traveled, and where we were. We did some more sampling. and then moved on toward Cone, into terrain that had almost continuous undulations, and very small flat areas. Soon after that, the surface began to slope upward even more steeply, and it gave us the feeling that we were starting the last climb to the rim of Cone. We passed a rock which had a lot of glass in it, and reported to Houston that it was too big to pick up.

We continued, changing our suit cooling rated to match our increased work output as we climbed. and stopping a couple of times briefly to rest. For a while, we picked up the cart and carried it, preferring to move this way because it was a little faster.

 
Apollo 14 Astronaut Shepard fits a core tube section to the extension handle in preparation for taking a vertical sample of the subsurface material. Core tubes were among the handtools carried on the MET.

And then came what had to be one of the most frustrating experiences on the traverse. We thought we were nearing the rim of Cone, only to find we were at another and much smaller crater still some distance from Cone. At that point, I radioed Houston that our positions were doubtful, and that there was probably quite a way to go yet to reach Cone.

About then, there was a general concurrence that maybe that was about as far as we should go, even though Ed protested that we really ought to press on and look into Cone crater. But in the end, we stopped our traverse short of the lip and turned for the walk back to Antares.

Later estimates indicated we were perhaps only 30 feet or so below the rim of the crater, and yet we were just not able to define it in that undulating and rough country.

One of the rocks we sampled in that area was a white breccia (a rock made up of pieces of stone embedded in a matrix). The white coloring came from the very high percentage of feldspar that was in the breccia. That rock, and others in the area, were believed to approach 4.6 billion years in age.

Beam cautiously removes hot fuel capsule from its graphite cask in order to insert it into the Radioisotope Thermoelectric Generator (RTG) at his right. The temperature of the capsule, which was filled with plutonium-238, is about 1350° F.


The RTG was the powerhouse for the entire experiment package. The temperature difference between the fuel capsule and the finned outer housing was converted into electrical power by 442 lead telluride thermocouples. Starting at about 74 watts, the output to the central station will continue for years at a slowly diminishing rate.

We stopped at Weird crater, for more sampling and some panoramic photography, and then continued the return traverse. At the Triplet craters, more than three-quarters of the way back to Antares, we stopped again. Ed's job there was to drive some core tubes; I was to dig a trench to check the stratification of the surface. But the core material was granular and slipped out of the tube every time Ed lifted it clear of the surface. I wasn't having any better luck with my trenching, because the side walls kept collapsing. I did get enough of a trench dug so that I could observe some stratification of the surface materials, seeing their color shift into the darker browns and near blacks, and then into a surprisingly light-colored layer underneath the darkest one.

That was it, Antares was in sight, as it had been throughout much of the traverse, and our long Moon walk was almost over. I went on past Antares to the ALSEP site to check antenna alignment because of reports from Houston that a weak signal was being received. Ed took some more samples from a nearby field of boulders.

With its three gold-covered booms outspread, the Lunar Surface Magnetometer can measure the three orthogonal components of the magnetic field. Periodically, the fluxgate sensors at the ends of the booms are flipped over mechanically to check the calibration. An astronaut initially oriented the instrument by means of the shadowgraph shown at the base of the X-axis (right) boom and the bubble level on the sunshade.


The Laser Ranging Retroreflector (LRRR) is a completely passive array of small fused-silica corner cubes that reflect incident light precisely back toward its sources. When the source is a pulsed ruby Laser at a large telescope, the distance from the LRRR to the ground station can be routinely measured within 6 inches. The three LRRR arrays on the Moon permit long-term studies of subtle Earth and Moon motions.

At that, our surface tasks were done, with the exception of recovering the solar-wind experiment and getting back into Antares for the return flight. We had covered a distance of about two miles and collected many samples during four and one-half hours on the surface in the second EVA. I also threw a makeshift javelin, and hit a couple of golf shots.

The top surface of the central station in an aluminum honeycomb sunshield. Before deployment, the antenna and several ALSEP experiments were attached to the brackets atop the sunshield with quick-release bolts. When raised, the sunshield and insulating side curtains provide thermal protection for the electronics. A leveling head on the antenna mast permitted the astronaut to aim the helical S-band antenna earthward.


A wavy golden ribbon connects the Apollo 14 Suprathermal Ion Detector and its accompanying Cold Cathode Gauge with the ALSEP central station some 50 feet away. This pair of instruments was also emplaced at the Apollo 12 and 16 sites. The wide range of the three Ion Detector look angles permits study of the directional characteristics of the flow of ions an both sides of the Earth's magnetospheric tail.

After liftoff there were still experiments left to do. The first of these was another seismic event, generated by the impact of the jettisoned Antares on the Moon. Again the Moon responded with that resonant ringing for some time after the event. Once we were on our way back to Earth, we did a series of four experiments in weightlessness. One was a simple metal casting experiment, to see what the effects of zero gravity would be on the purity or the homogeneity of the mass. The materials included some pure samples, and others with crystals or fibers for strengthening. As you might expect, the materials turned out to be more homogeneous under zero-gravity conditions. We measured heat flow and convection in some samples and, sure enough, zero gravity changed those characteristics also. We did some electrophoretic separations, which are techniques used by the pharmaceutical industry to make vaccines, in the belief that maybe zero-gravity conditions could simplify a complex and expensive process. Finally, we did some fluid transfer experiments, simply trying to pour a fluid from one container to another in zero gravity. The surface tension works against you there, and so it was much easier when the containers being used were equipped with baffles that the fluid could cling to, as it were.

 
The Passive Seismic Experiment is completely hidden by its many-layered shroud of aluminized Mylar. The top of the thermal shroud is the platform for the bubble level and Sun compass that the astronaut used to orient the experiment initially. An internal set of leveling motors keeps the seismometers constantly level within a few seconds of arc. Seismic motions are recorded on Earth with a magnification factor of 10 million. The network created by the four ALSEPs that have this experiment enables seismologists to locate moonquakes in three dimensions, and to study the seismic velocities and propagation characteristics of subsurface materials.

That was our mission. Our return was routine, our landing on target, and our homecoming as joyous as those before.

I look back now on the flights carrying Pete's crew and my crew as the real pioneering explorations of the Moon. Neil, Buzz, and Mike in Apollo 11 proved that man could get to the Moon and do useful scientific work, once he was there. Our two flights- Apollo 12 and 14- proved that scientists could select a target area and define a series of objectives, and that man could get there with precision and carry out the objectives with relative ease and a very high degree of success. And both of our flights. as did earlier and later missions, pointed up the advantage of manned space exploration. We all were able to make minor corrections or major changes at times when they were needed, sometimes for better efficiency, and sometimes to save the mission.

Like any tourist in a strenge place, Ed Mitchell consults a map on his way to Cone crater. He was photographed by his companion, Alan Shepard, during the second Apollo 14 EVA. During their 9 hours on the lunar surface, these tourists collected 95 pounds of lunar samples to bring home. Their main complaint during their stay was the way the lunar dust stuck to their suits almost up to their knees.

Apollo 12 and 14 were the transition missions. After us came the lunar rover, wheels to extend greatly the distance of the traverse and the quantity of samples that could be carried back to the lunar module. And on the last flight, a trained scientist who was also an astronaut went along on the mission.

I'd like to look on that last flight as just a temporary hold in the exploration of space.

 
The flag flutters an the Moon in the genuine wind of a rocket exhaust as the ascent stage of the Apollo 14 lunar module Antares lifts off from the Moon. Pieces of the gold-coated insulating foil turn off the descent stage by the blast were also sent flying. Who knows how many thousands of years will pass before a wind of vaporized rock from some nearby meteorite impact once more sets this flag flapping?


In the blackness of space, the Apollo 14 command-service module Kitty Hawk gleams brilliantly as it draws near the camera in the lunar module Antares. The single-orbit rendezvous procedure, used for the first time in lunar orbit on this mission, brought the two craft together in two hours. After crew transfer, Antares was guided to lunar impact at a point between the Apollo 12 and 14 sites. The resulting seismic signal, recorded by both instruments, lasted 1 1/2 hours.


At its journey's end, the Apollo 14 command module splashes down into the sparkling South Pacific, some 900 miles south of Samoa. The parachutes collapse as they are freed of their load. On this occasion, the command module remained right side up in the water after landing. Like a kayak, a command module was just as stable in the water when it was upside-down (stable two). If it toppled over to an inverted position, as happened on other splashdowns, the crew could right it by means of inflatable airbags.


 
Astronauts Mitchell, Shepard, and Roosa, and a recovery team frogman wait aboard the raft Lily Pad for a helicopter pickup. With the hatch open, the command module was vulnerable to swamping, along with its priceless load of lunar samples and film, which is why frogmen routinely lashed an inflated flotation collar around a spacecraft.


 
The veritable pay dirt of the Apollo expeditions is the collection of lunar samples that is now available for the most detailed examination and analysis. Scientists have long been aware that our understanding of the nature and history of the solar system has been biased in unknown ways by the fact that all of the study material comes from one planet. Although meteorites are fascinating samples of the material of the solar system at large, there is never any direct evidence of the source of an individual meteorite. Now, within a few years, mankind has assembled the material of another world, recording where each piece came from and what was nearby. Here, scientists at the Lunar Receiving Laboratory work with an Apollo 14 sample in a sterile nitrogen atmosphere.