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FIRST PHASE OF LUNAR EXPLORATION COMPLETED:
Intrepid Seeks Out Surveyor III
The morning of November 14, 1969, was cold, cloudy, and wet at Kennedy
Space Center. Weather radar showed rain showers marking a cold front 80
miles (130 kilometers) north of the Cape and moving south. With launch
only hours away, rain, broken low clouds, and overcast at 3,000 meters
(9,800 feet) caused launch officials to consider their options. Reports
indicated no thunderstorms or severe turbulence in the area, however,
and conditions were better than the minimums specified by launch rules.
An hour and 22 minutes before liftoff, a pump replenishing liquid oxygen
in the launch vehicle tanks failed. With success depending on a backup
pump, launch director Walter Kapryan chose to proceed.1 The crew had trained intensively for the
specific features of the planned landing site, and if the day's launch
window closed, that site would not be accessible for another month.
At 11:22 a.m. Eastern Standard Time, President Richard M. Nixon - the
only incumbent chief executive ever to witness an Apollo launch - along
with 3,000 invited guests and a large crowd of tourists, watched as the
Saturn V rose from the pad and accelerated toward the clouds. Just
before the vehicle disappeared into the overcast, two streaks of
lightning flashed toward the launch complex. In the command module
Yankee Clipper, mission commander Pete Conrad heard the
master alarm. He looked at the caution and warning panel, and "it
was a sight to behold." Sixteen seconds later another bolt
discharged, and Conrad told Houston, "We just lost the platform [in
the inertial guidance system], gang: I don't know what happened here; we
had everything in the world drop out."2 The fuel cells had automatically disconnected
and several panel gauges were temporarily disturbed, but otherwise
everything seemed normal. After the crew reset the fuel cells, the
flight continued while Mission Control tried to figure out what had
happened and what the consequences might be. The best guess seemed to be
that the launch vehicle, trailing its plume of ionized (and electrically
conductive) exhaust gas, had triggered a lightning discharge that
otherwise would not have occurred. Except for nine telemetry sensors not
essential to the flight, all systems were normal.3
Apollo 12 flew smoothly into a normal earth orbit, and after the
inertial guidance system was realigned and all systems checked out,
Houston gave the signal to fire the S-IVB stage for translunar
insertion. Three and a half hours into the flight, command pilot Richard
F. Gordon turned command module Yankee Clipper around,
extracted the lunar module Intrepid from its stowage site
atop the third stage, and Apollo 12 continued on its way to
the moon.4
The only midcourse correction maneuver of the outbound flight was
performed the next day, a 9.2-second burn that put the spacecraft on a
fuel - saving hybrid trajectory.5 For
the rest of the uneventful three-and-a-half-day trip to lunar orbit, the
crew spent their time housekeeping, tending to spacecraft systems, and
observing the earth and the moon.6
Arriving at the moon 83 1/2 hours after liftoff, Conrad fired the main
propulsion engine for almost 6 minutes to go into an elliptical lunar
orbit. Five hours later a second burn put the spacecraft into a circular
orbit at 60 nautical miles (111 kilometers) altitude, where Yankee
Clipper would stay until it was time to return to earth. The
spacecraft passed over and photographed Apollo 13's landing area in the
Fra Mauro formation, and on the tenth revolution Conrad notified Capcom
Gerald Carr that "you can tell good Captain Shaky [Jim Lovell,
commander of Apollo 13] that he can relax. We've got his
pictures."7
Six hours into the fourth day, Conrad and Bean prepared to enter and
activate the lunar module. Both were having trouble with their
biomedical sensors; Conrad's were blistering his skin and Bean's were
producing erratic signals. Both men cleaned and reattached their
electrodes, then finished donning their space suits and began preparing
Intrepid for departure.8
For the next several hours Conrad and Bean in Intrepid and
Gordon in Yankee Clipper were busy setting up their
guidance and navigation computers and exchanging data with the ground.
When all was ready, Gordon turned the spacecraft so that the long axis
of the command and service module was perpendicular to the flight path
with the lunar module outward from the moon, retracted the docking
latches, and fired his attitude-control thrusters to move Yankee
Clipper away from Intrepid.9 The landing craft was 5 miles (8 kilometers)
north of its intended ground track - largely as a result of an error in
the landing site location and the inability to adequately correct for
the moon's irregular gravity field. This and other errors would be
removed by the instructions transmitted to the guidance computer after
the lunar module headed down for its landing.10
On the back side of the moon in the 13th revolution, the computer
triggered a 29-second firing of the descent engine, bringing the low
point of Intrepid's orbit to 8.1 nautical miles (15
kilometers). As the lander passed north of Mare Nectaris, Conrad turned
it on its back with the descent engine pointed along the flight path and
switched the engine on to begin the final approach. Everything went
exactly as expected, and after two minutes Conrad commented that it
"feels good to be standing up in a g-field again." Three
minutes later the module's attitude-control thrusters began firing
busily - more than Conrad thought they should - but Houston assured him
that all was well.11
After seven minutes Intrepid nosed over into a near-upright
position and for the first time Conrad could see the lunar surface. The
principal landmark identifying his landing point was a pattern of
craters the astronauts called "Snowman"; Surveyor
III lay halfway up the eastern wall of the crater that was the
Snowman's torso, and Intrepid was targeted for the center of the crater.
As soon as he could see out the window, Conrad cried delightedly,
"Hey, there it is [Snowman]! There it is! Son of a gun! Right down
the middle of the road!" Then, as Bean called out altitude,
velocity, and quantity of fuel remaining; Conrad maneuvered the craft
with his hand controller to pick a smooth spot to land on. The engine
exhaust began kicking up dust about a hundred feet (30 meters) above the
surface and by the time Intrepid reached 50 feet ( 15
meters) the cloud obscured the surface completely. At 1:54:36 a.m. EST
on November 20, Pete Conrad made a blind landing - exactly where, he
could not tell, but certainly close to the intended spot.12
Conrad was naturally anxious to determine where he had set
Intrepid down, and while he and Bean went through the
post-landing check list they occasionally looked out the windows for
landmarks that would allow Houston to pinpoint their location, but
without success. After changing his mind a time or two, Conrad finally
concluded, "I'm not sure that I'm not sitting fight smack on the
other side of the Surveyor crater, just a little bit past it." Two
hours later, Dick Gordon in Yankee Clipper confirmed
Conrad's guess when he sighted both Intrepid and
Surveyor III through his sextant as he passed over the
site. He told Houston that the lunar module was "on the left
shoulder of the Snowman. . . , about a third of the way from the
Surveyor crater to the head.13
Postmission calculations placed Intrepid on the northwest
rim of the Surveyor crater, 535 feet (163 meters) from the inert
spacecraft.14 Had there been windows in
the back of the lunar module, Conrad could have spotted the Surveyor as
soon as the dust settled.
After postlanding checks of systems, Conrad and Bean described what they
could see from their spacecraft. Intrepid had landed in
undulating terrain pocked with craters ranging from a few feet to
several hundred feet across, the larger ones rimmed by large blocks of
rock. Numerous boulders, up to 20 feet (6 meters) in size, were
scattered around the site, most of them angular rather than rounded,
many showing fillets of dust around the base. Immediately in front of
the landing craft Bean saw an area of "patterned ground" -
parallel cracks in the surface soil perhaps an eighth of an inch (3
millimeters) deep. From the lunar module the crew could distinguish no
color differences in the rocks or soil; everything seemed the same
bright white.15 Five and a half hours
after landing, Conrad squeezed out the hatch, then clambered down the
ladder to the bottom rung. As he stepped off onto the landing pad Conrad
remarked, "Man, that [step] may have been a small one for Neil, but
that's a long one for me."*
Looking around, he spotted the Surveyor halfway up the opposite wall of
the crater. One of the first things Conrad noticed was that he was going
to get extremely dirty: the surface dust was finer and deeper than he
had expected.16
After Conrad had collected the contingency sample Bean joined him on the
surface, bringing the television camera with him. A few minutes later
Houston reported that the camera was not working. Cursory attempts at
trouble-shooting were fruitless, and television coverage for the mission
- desirable but not essential - had to be written off.** 17 The
explorers pressed on with their other chores, apparently enjoying
themselves immensely; Conrad chuckled and hummed to himself as he went
about examining the lunar module, collecting and photographing samples,
and describing the landscape.18
The primary objective of their first excursion was to deploy the
scientific experiments. Conrad and Bean unloaded the package easily,
picked a spot 130 meters (425 feet) northwest of the lander, and laid
out the instruments without any serious difficulty.19 On their way back to Intrepid
they picked up more documented samples and Bean took a soil sample with
the core tube. After nearly four hours on the surface, the astronauts
returned to the lunar module, dusted each other off as best they could
without brush or vacuum cleaner, and climbed back inside. After a brief
evaluation of the day's work and some discussion of the next day's
plans, Houston signed off and the two astronauts strung up their
hammocks and turned in.20
Overnight the geologists in Houston, working from several scenarios
prepared before the mission, formulated detailed plans for the geology
exercise the astronauts would carry out on their second outing. Next
morning, when Bean and Conrad were awake and ready to talk, CapCom Paul
Weitz read through the plans with them, discussing the scientists'
recommendations for sampling and photography, while the astronauts
offered comments based on the previous day's experience. Then they domed
and checked over their space suits, recharged with oxygen their portable
life-support systems, vented the cabin, and set out to collect
samples.21
During the next four hours Bean and Conrad covered something more than
one kilometer (3,300 feet), following a large-scale photographic map
prepared for the traverse and chatting constantly with each other and
with Houston.22 Scientists in Houston
followed their progress from their references to the maps they carried.
The extensive conversation was intended to substitute for a geologist's
field notes.23 On the nearly
featureless lunar surface, sampling proved somewhat difficult; except
for size, most of the rocks showed few distinguishing features. Colors
and textures were not always easy to determine, and when they were, the
astronauts tended to use nonscientific terms in describing them -
probably a symptom of their sensitivity to possible misuse of geological
terminology. At one point Conrad noted a rock containing a
"ginger-ale-bottle green" crystal (which was probably
olivine), and a few minutes later Bean spotted a rock he said
"looks almost like a granite," but immediately added, "of
course it probably isn't, but it has the same sort of texture."
Bean and Conrad documented their samples carefully, photographing many
of them and describing the location and bag number for later reference.
At "Head" crater, following instructions from Houston, Conrad
dislodged a medium-sized rock and allowed it to roll down the slope to
determine whether the seismometer some 70 meters (230 feet) away could
detect it (it did). Then it was on to "Bench" and
"Sharp" craters, where they sampled several large rocks on the
surface that might be bedrock thrown out when the craters were formed.24
Two hours into the traverse the astronauts were on the edge of the
Surveyor crater. The slope of the crater wall was much less than it had
appeared the day before, when the low sun cast long, deceptive shadows.
Pausing to reload a camera and survey the situation, they decided it
would be easier to walk across the slope of the crater wall rather than
come down from the rim. Approaching from the side, they could take
photographs of the landing-pad imprints and the trenches dug by
Surveyor's remotely controlled arm without disturbing the surface. These
would be compared with television pictures transmitted from the
spacecraft immediately after its landing.25
Examination of the Surveyor, the only human artifact ever encountered in
lunar exploration, was among the more interesting parts of the mission
for Conrad and Bean. What they noticed first was that much of its
originally white surface had turned brown - a change they attributed to
a deposit of dust when they found it could be wiped off. After
photographing the surrounding surface and examining the spacecraft, they
removed the Surveyor's television camera and cut off pieces of
electrical cable and structural tubing for study by scientists at the
Jet Propulsion Laboratory. They decided to remove the trenching scoop as
well; then, after collecting soil samples, they headed for another small
crater to take a few more samples on their way back to the lunar
module.26
Back in their spacecraft, Conrad and Bean had almost six hours before
lifting off to rendezvous with Yankee Clipper. After
throwing out their portable life-support systems they straightened up
the cabin, stowing the rock boxes and improvising stowage for the
television camera, which Houston wanted to examine. They had carried in
considerably more lunar dust than Armstrong and Aldrin had reported;
Conrad told Houston they looked like "a couple of bituminous coal
miners right at the moment, but we're happy."27
Despite the fact that they had trebled the existing record for lunar
surface activity, Bean and Conrad were not exhausted and had expended
about 10 percent less energy than anticipated. Both returned to the
lunar module with almost 40 percent of their oxygen supply remaining on
both excursions.28 Bean suggested to
the medical officers that he would have enjoyed an occasional drink of
water while working on the surface; not that he felt dehydrated, but he
would have been more comfortable if he had been able to relieve the
dryness in his mouth.29
Intrepid's ascent stage lifted off the moon on time, and an
hour and a half later Conrad had Yankee Clipper in sight.
Back in lunar orbit the dust the lunar explorers had brought in with
them began to float, thick enough to be visible in the cabin. After the
two spacecraft had docked they attempted to vacuum up the dust, with
little success, so they removed and packaged their suits in the lunar
module, hoping to minimize contamination of the command module. In spite
of their efforts, considerable dust clung to everything they brought
back and remained suspended in the atmosphere; the environmental control
system seemed not to filter it out as completely as had been expected.30
Intrepid, now a useless hulk, still had one more
contribution to make to the scientific objectives of the mission. For
the benefit of seismologists wanting to calibrate the instrument that
Bean and Conrad had just left on the moon, Mission Control now burned
the empty spacecraft's remaining fuel to take it out of orbit. At a
speed of 1.67 kilometers per second (3,735 miles per hour) the ascent
stage plowed into the moon 76 kilometers (47 miles) east-southeast of
the instrument package, producing a bizarre response: the seismometer
recorded vibrations that persisted almost undiminished for nearly an
hour. It was so completely unlike anything ever seen on earth that
seismologists had no immediate explanation. One scientist compared the
result to striking a church bell and hearing the reverberations for 30
minutes.31
Yankee Clipper stayed in lunar orbit for 11 more
revolutions, finishing up the "bootstrap" photography and
landmark tracking, looking at sites being considered for Apollo 14 and
15. Then the crew boosted their spacecraft out of lunar orbit and
settled in for the three-day voyage home. Now and then they chatted with
the duty CapCom about something that crossed their minds concerning
their exploration. Once in a while scientists wanted to debrief them
concerning details of their lunar surface activity. For most of the
time, however, they relaxed.32
At one point both Conrad and Bean passed along some reservations they
had about the field geology exercise. They had found the lunar surface a
particularly difficult one for classical field-geological techniques.
Bean commented,
. . . we talked with [the geologists], before we went,
about [the fact that] the main objectives of the geology wasn't to go
out and grab a few rocks and take some pictures, but to try to
understand the morphology and the stratigraphy . . . of the vicinity you
were in. Look around and try to use your head along those lines. Well,
I'll tell you, there [were] less than ten times I stood in spots ... and
said, "Okay now, Bean, . . . is it possible to look out there and
try to determine . . . which is first, which is second, and all
that?" . . . That whole area has been acted on by these meteoroids
or something else so that all these features that are normally neat
clues to you on earth are not available for
observation.
Conrad concurred: "I think even a trained geologist would have
trouble doing a whole lot of field geology that way on the moon."33 Long afterward, Bean still felt that
astronauts could be most effective on the lunar surface by selecting and
documenting as many apparently different kinds of samples as possible
rather than attempting on-the-spot geologizing.34 During a press conference on the last day out,
Conrad was asked whether he thought it would be desirable to have a
geologist as a member of the crew. He did indeed think so, but pointed
out that landing Intrepid had required all the piloting
skill he had35 - implicitly echoing
Deke Slayton's contention that landing on the moon was not yet a job for
a novice.
Early on the morning of November 24 Apollo 12 splashed down
some 600 kilometers (375 miles) east of Pago Pago, 3.5 kilometers (2
miles) from the recovery ship U.S.S. Hornet. The landing
was rough - apparently Yankee Clipper hit a rising wave as
it swung on its parachutes - hard enough to dislodge a 16-mm movie
camera from its bracket and slant it into Alan Bean's forehead,
momentarily stunning him and opening a 1-inch (2.5-centimeter) cut,
which Conrad bandaged.36
The recovery swimmers soon arrived, tossed respirators and coveralls -
replacing the biological isolation garments that the Apollo 11 crew had
found so objectionable - into the command module, then assisted the
astronauts into the raft. Half an how later recovery helicopters set the
crew down aboard the Hornet and they went straight to their mobile
quarantine facility. Lunar sample containers and film magazines were
removed and flown to Pago Pago and thence to Houston. The astronauts had
a longer journey: four days aboard ship to Hawaii, then a nine-hour
flight to Houston. On the morning of November 29, Conrad, Bean, and
Gordon entered the Lunar Receiving Laboratory for their 11-day stay in
quarantine.37
That Apollo 12 was a success was apparent even on preliminary
evaluation. The procedural changes incorporated to improve landing
accuracy had allowed Conrad to put Intrepid down within sight of
Surveyor III, exactly as intended. Lunar exploration had
been easy; neither Bean nor Conrad encountered any unexpected
difficulties and both had oxygen to spare when they returned. And while
they had found it hard to apply their field - geology training on the
unrevealing surface of Oceanus Procellarum, they had collected nearly 75
pounds (34 kilograms) of samples, most of them documented. The surface
experiments they had set up were returning streams of data, and
scientists agreed the astronauts had done a remarkable job.
Communication between scientists in Houston and the astronauts on the
moon had been well handled by Mission Control.38 If Apollo 12 was a reliable indicator, the
scientific return from the remaining eight missions should be
gratifying.
* At 5 feet 6 inches (168
centimeters), Conrad was one of the shorter astronauts; Armstrong was
just under 6 feet (183 centimeters). The lowest rung of the ladder was
about 2.5 feet (75 centimeters) above the landing pad.
** Later examination determined that
the image-tube target in the camera had been damaged by exposure to
intense light. Apparently Bean had inadvertently pointed the camera at
the sun or a reflection off the lunar module while helping Conrad set up
a directional antenna. MSC-01855, "Apollo 12 Mission Report,"
March 1970, p. 14-50,
1. Charles D. Benson and William Barnaby
Faherty, Moonport: A History of Apollo Launch Facilities and
Operations, NASA SP-4204 (Washington, 1978), pp. 481-82.
2. Ibid.
3. MSC, "Apollo 12 Technical
Air-to-Ground Voice Transcription," prepared for Data Logistics
Office, Test Div., Apollo Spacecraft Program Office, Nov. 1969 (cited
hereinafter as "12 Air-to-Ground"), p. 17; MSC, "Apollo
12 Mission Report," MSC-01855, March 1970, pp. 14-2 to 14-4.
Postflight analysis of available data supported the first tentative
conclusion. Electric-field measurements at the launch site indicated
that the clouds were charged, but not enough to produce lightning. The
passage of a conductor (such as the launch vehicle) is known to produce
lightning under such conditions. Witnesses disagreed on the question of
lightning strikes, but photographs showed two bolts from cloud to ground
36.5 seconds after launch, neither of which produced damage. The second
discharge, 52 seconds after launch, was probably between clouds. See
MSC-01540, "Analysis of Apollo 12 Lightning Incident," Feb.
1970. Damage to the launch vehicle was negligible (several telemetry
sensors on the service module were knocked out), but launch rules were
subsequently tightened to forbid launch under weather conditions
favorable to lightning strikes.
4. 12 Air-to-Ground, p. 24.
5. Apollo 12 Mission Report, p. 5-4.
6. Ibid., p. 5-5.
7. 12 Air-to-Ground, p. 292.
8. Ibid., pp. 281-92.
9. Ibid., pp. 292-322.
10. Apollo 12 Mission Report, pp. 5-7 to
5-8.
11. 12 Air-to-Ground, pp. 335-45; Apollo
12 Mission Report, p. 5-9.
12. 12 Air-to-Ground, pp. 346-68; Apollo
12 Mission Report, p. 6-3.
13. 12 Air-to-Ground, pp. 348-68.
14. Apollo 12 Mission Report, pp. 4-25
to 4-27.
15. 12 Air-to-Ground, pp. 370-73.
16. Ibid., pp. 406-ll.
17. Ibid., pp. 418-26; Apollo 12 Mission
Report, p. 14-50.
18. 12 Air-to-Ground, pp. 429-60.
19. Apollo 12 Mission Report, p. 3-26;
12 Air-to-Ground, pp. 438-73.
20. 12 Air-to-Ground, pp. 473-521. Neil
Armstrong and Buzz Aldrin had difficulty finding a way to sleep
comfortably in the cramped LM. Hammocks were added on Apollo
12 and Bean and Conrad found them quite comfortable in lunar
gravity.
21. 12 Air-to-Ground, pp. 553-89.
22. Ibid., pp. 597-716.
23. The Lunar and Planetary Missions
Board recommended in early 1968 that astronauts should talk as much as
possible ("almost incessant talking," as the Board put it)
while on the lunar surface, describing what they were doing, what they
could see and how they interpreted it, and what they intended to do next
and why, to provide a complete record of their surface activity, Homer
E. Newell to Robert R. Gilruth, Feb. 5, 1968. MSC agreed in principle
only, suggesting that the astronauts observe the tried and proven rules
of aircraft communications, transmitting only necessary information
while at the same time making an effort to provide "a running
commentary of significant events and actions so preplanned that normal
communications discipline is not violated but yet is complete enough to
assure a maximum of scientific return from the exercise." That kind
of commentary would be "comparable to the usual field notes of the
practicing geologist on a field trip." Gilruth to Newell, Feb. 20,
1968; W. N. Hess to Special Asst. to the Dir., "Astronaut Activity
on Lunar Surface," Feb. 19, 1968.
24. 12 Air-to-Ground, pp. 602, 603,
614-52. After Buzz Aldrin drew criticism from scientists for his
misidentification of biotite (see footnote, chap. 9, p. 282), Bean and
Conrad may have been more sensitive to what they were saying.
Geologist-astronaut Jack Schmitt noted that in postmission discussions
Conrad admitted he was fairly sure the sample was olivine, but "he
wasn't about to say so," for fear of making a mistake. H. H.
Schmitt interview, May 30, 1984.
25. 12 Air-to-Ground, pp. 661, 666, 670.
26. Ibid., pp. 671-95.
27. Ibid., p. 731.
28. Apollo 12 Mission Report, pp. 10-7,
8-20.
29. Ibid., p. 9-10; 12 Air-to-Ground, p.
740.
30. 12 Air-to-Ground, pp. 757-770; MSC,
"Apollo 12 Technical Crew Debriefing," Dec. 1, 1969, pp. 12-21
to 12-23; Apollo 12 Mission Report, pp. 6-5 to 6-6.
31. Apollo 12 Mission Report, pp. 3-10
to 3-11, 9-39 to 9-40; Victor Cohn, "Moon Quake Caused by Lem
Called 'Unlike Any' on Earth," Washington Post, Nov.
21, 1969; Gary V . Latham, Maurice Ewing, Frank Press, George Sutton,
James Dorman, Hosio Nakamura, Nafi Toksoz, Ralph Wiggins, and Robert
Kovach, "Passive Seismic Experiment," in Apollo 12
Preliminary Science Report, NASA SP-235 (Washington, 1970) , pp.
39-53.
32. 12 Air-to-Ground, pp. 863-1066,
944-57; Apollo 12 Mission Report, p. 9-28.
33. 12 Air-to-Ground, pp. 924-25.
34. Alan L. Bean interview, Apr. 10,
1984.
35. 12 Air-to-Ground, p. 1018.
36. Apollo 12 Technical Crew Debriefing,
pp.16-1, 16-4.
37. Apollo 12 Mission Report, pp. 11-6
to 11-7.
38. Cohn, "Moon Quake Caused by
Lem."
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