Apollo 11 Summary
Table of Contents
Mission Profile
- Launched: July 16, 1969
- Landed on the Moon: July 20, 1969
- Landing Site: Sea of Tranquillity
- Returned to Earth: July 24, 1969
- Command Module: Columbia
- Lunar Module: Eagle
- Crew
Neil A. Armstrong, commander
Edwin E. Aldrin, Jr., lunar module pilot
Michael Collins, command module pilot
- Backup Crew
James Lovell, backup commander
Fred Haise, backup lunar module pilot
William A. Anders, backup command module pilot
A Small Step in Learning to Walk
In his commentary on the Apollo 17 transcript, Gene Cernan says that,
in his experience, landing a jet on an aircraft carrier at night is
more difficult than landing the LM. Certainly, in the LM he had plenty
of help from Earth; visibility was good; and there were no winds or
waves to move the target around. Still, the LM was an experimental
craft and the vehicle that Neil Armstrong and Buzz Aldrin landed was
only the fourth that had ever been flown. And, of course, no carrier
landing had ever had quite the historic overtones of Apollo 11; nor
had any carrier landing ever been performed before so large an audience.
Literally billions of people listened as it happened.
Down to 50,000 feet above the Moon, Apollo 11 was little different
from 10. Armstrong, Aldrin, and Command Module Pilot Mike Collins
had a flawless launch from Earth, a long, uneventful coast out to
the Moon, and a nominal engine burn to put themselves into lunar
orbit. As they crossed over the Sea of Tranquillity for the first
time, Armstrong remarked that "the pictures and maps brought back
by Apollo 8 and 10 have given us a very good preview of what to
look at here. It looks very much like the pictures; but, like the
difference between watching a real football game and watching it
on TV, there's no substitute for actually being here." On that first
orbit, the planned landing site itself was still enveloped in pre-dawn
darkness and it wasn't until their fourth pass - during the LM checkout
- that Aldrin reported seeing it from the LM windows.
Site Selection
In his excellent book To a Rocky Moon, geologist Don Wilhelm's
discusses the process by which Apollo landing sites were chosen. After
Apollo 12, scientific considerations were given considerable weight
but, for the very first landing, the site was chosen entirely for
operational reasons. During the Lunar Orbiter missions, the high resolution
cameras had been focused on promising sites strung out along a 10-degree-wide
band straddling the lunar equator. Equatorial sites were of interest
because they could be reached with a minimal expenditure of fuel.
Sites were also sought at least 45 degrees west of the east limb of
the Moon - the right edge as seen from the northern hemisphere on
Earth - because the landers were going to orbit from east to west
and Houston was going to need several minutes of tracking data so
that the landing computer could be updated prior to the descent. As
Jack Schmitt related during a review of this introduction, "The targeted
point for Apollo 8 was picked as the easternmost site that the Flight
Control Division thought they could handle, the easternmost certified
(acceptably smooth) site for which they thought there would be enough
time after AOS (Acquisition of Signal) to track the Lunar Module,
update its state vector, and get a successful landing. So Apollo 8
was targeted for that site (designated as Apollo Landing Site 1) and,
when it came time for Apollo 10, they targeted it to the same site,
because they already had a rough data package (that is, data on orbits
and the timing of events during the mission) that they could refine
based on the relative positions of the Earth and Moon at the planned
time of launch. (Launch times were picked in part, so that, at the
time of landing, the Sun would be between 5 and 13 degrees above the
landing site horizon, low enough to give good shadow definition of
the terrain and not so low that everything would be obscured by overly-long
shadows. Lighting conditions at the Cape and at abort recovery sites
were also factors.)
"When I heard that they were going to target Apollo 10 for the
Apollo 8 target site, I went to Tom Stafford and said, 'Tom, you
know, this is really not the most efficient way to prepare for Apollo
11. First, we've already seen the Apollo 8 site, admittedly from
high orbit (60 miles altitude), and we came away with some confidence
that it was acceptable. Second, if we target Apollo 10 for the next
certified site west (certified landing sites were spaced about 12
degrees apart - about the distance the sunrise line moves in 24
hours - in case there was a launch delay and you didn't want to
have to wait a whole month), the fact that Apollo 10 is going to
spend an extra day in orbit means that, by the time you're ready
to leave, the Sun will have risen on the third site. So, by the
end of Apollo 10, we will have three options for Apollo 11.' That
was my basic argument. And Tom liked the idea.
"So I worked out more of the detail and began to raise the idea
up the chain of command. One of the people we briefed was Jerry
Hammack, the Recovery Chief, who was in charge of recovery back
here on Earth. We had stuck something in our arguments to get his
attention because, had we maintained the Apollo 8 target for Apollo
10, we would have had a pre-sunrise, quasi-nighttime splashdown.
And he'd been nervous about that. We didn't know how nervous, but
it didn't seem like a good idea to us and, by retargeting to the
next site, you ended up with a post-sunrise splashdown in the Pacific.
And when we briefed Chris Kraft, the discussion went back and forth
and, just as I paused, Jerry said 'All that and a daylight landing,
too!' And that impressed Chris and I think he became an advocate
then.
"But then we took it up to the next level, late one night, to George
Low and Sam Phillips, who were in town (Houston), and gave them
the whole presentation. And when we left the room, George had indicated
that he didn't think it was a good idea. Sam had not indicated one
way or the other, but did say that we were just too far down the
line to change the data pack. So, when Tom and I left, we were sort
of discouraged. But the next morning, Tom called me and said that
George had changed his mind. And I said, 'I think Sam Phillips changed
George's mind.' But, whatever the reason for it, they said go ahead
and target for the next landing site. And that ended up being Tranquillity
Base. When we got to Apollo 11, there was no question. We knew we
had plenty of time after coming around the limb, the tracking had
been done (on Apollo 10), and we'd seen the sight close up (from
9 miles rather than 60). And even I couldn't argue that we ought
to go further west."
Preparing for the Descent
Eighty six hours and five-and-a-half lunar orbits into the mission,
the crew of Apollo 11 settled down for their last rest period before
the landing. As Jack Schmitt relates in his Apollo 17 commentary,
six hours of intermittent sleep in orbit can be as restful as six
hours of uninterrupted sleep on Earth and, during the outbound trip
from Earth, the Apollo 11 crew had been getting between 9 and 10 hours
during each of the rest periods. The final rest before the landing
was necessarily a short one, but the three of them each got six hours
of deep sleep. When the wake-up call - answered by a very groggy Mike
Collins - came at ninety-three hours into the mission, they were rested
for the historic day ahead.
For the next eight hours, Armstrong, Aldrin, and Collins got ready
for the descent. By the time they disappeared behind the Moon for
the fourteenth time, they were suited and undocked, and just minutes
away from the 30-second burn that would put the LM on the Apollo
10 descent trajectory down to 50,000 feet. Collins would remain
in a circular orbit 60 nautical miles above the Moon and, because
of his higher altitude, it was he who was first to regain radio
contact with Earth. Everything had gone well. The LM would be coming
around the corner in just a moment and right on time.
There were no seats in the LM. Armstrong and Aldrin were standing,
held in place by elastic cords attached to the flooring. For sixteen
minutes they looked out the windows and timed the passage of landmarks
below them (across a scale marked on Armstrong's window) to confirm
the tracking data that Houston was getting. With Houston's help,
they also checked and double checked the health of the LM.
The Lunar First Landing
When the twelve-and-a-half-minute descent burn finally began, they
had the spacecraft oriented so that they were flying with their feet
and the engine forward. They were also flying with the windows facing
the Moon so that they could do some post-ignition landmark timing;
but then, as planned, three minutes into the burn Armstrong rotated
the spacecraft to a face-up position. Now, he and Aldrin needed to
fly with their backs to the Moon so that, as they approached the landing
site and the LM began to rotate upright, Armstrong would be able to
see the ground ahead and pick out a good, clear landing spot. As they
flew, they monitored the LM's performance and the readouts of the
guidance computer. All of the data indicated that they were flying
very close to the planned trajectory.
If, as Cernan suggests, landing on the Moon was easier than landing
on an aircraft carrier at night, one of the many advantages was
the fact that the LM was equipped with what was - for the time -
a sophisticated on-board computer that did much of the routine work
of flying the spacecraft. During all but the final moments of the
approach, flying the proper trajectory was a matter of analyzing
navigation data from inertial and radar systems and then subtly
adjusting the thrust and pointing of the LM engine. It was a labor-intensive
task and a job well suited to computer control. Not until after
an event called pitchover - when the spacecraft rotated from 60
degrees off vertical to 20 degrees - did the astronauts' roles become
more than that of monitor-and-backup.
Several times during the descent, the computer flashed alarms.
The trajectory looked good but the "1202" message - like a later
"1201" - wasn't one that the crew recognized and there were a few
tense seconds until Houston radioed "We're GO on that alarm." As
it turned out, parts of the computer memory were being overloaded
with extraneous data from the rendezvous radar and, fortunately,
not only had the computer been programmed so that it could continue
to handle high priority tasks but, also, the person who knew the
computer best - engineer Steven Bales - needed only a few seconds
to diagnose the problem and recommend that the landing continue.
Bales later stood beside the crew at a White House ceremony and
was decorated for his singular contribution to the success of the
mission.
The on-board computer handled a variety of tasks during the descent
and, in addition to the unanticipated flood of data from the radar,
there were also annoying, computer-related losses in communications
with Earth. The LM was equipped with a pair of broad-beam, "omni-directional"
antennas, but a high rate of data transmission could be achieved
only through use of a narrow-beam, steerable antenna. It was the
computer's job to maintain proper spacecraft orientation so that
the high-gain antenna could maintain a lock on Earth. The computer
had been instructed to avoid certain spacecraft orientations which
would force the antenna to look through the LM and, thereby, lose
enough signal strength that the "lock" on Earth would be lost. However,
the computer had been given an inaccurate "map" of the LM and loss
of signal was a recurring problem throughout the descent. Because
the precise landing spot was not critical on this first mission,
all that Houston needed was enough information to be sure that the
spacecraft was operating properly and, through the combined use
of the omni antennas and voice relays through Collins in the Command
Module, adequate communications was maintained.
The program alarms and the communications dropouts were annoying
but in all other respects, the LM computer and the navigation system
performed beautifully. Eight minutes and thirty seconds into the
burn, the computer pitched the LM nearly upright and Armstrong got
his first close-up view of the place to which the computer was taking
them. He was about 5000 feet above and about 20,000 feet east of
it. As planned, he had fuel enough for five more minutes of flight.
Each of the astronauts had a small, double-paned, triangular window
in front of him. On the inner surface of each pane in Armstrong's
window, there was a long vertical scale marked in degrees and, at
right angles to it, a similar but shorter horizontal scale. At pitchover,
Armstrong positioned himself so that the vertical scales were aligned;
and Aldrin read a computer output to him that indicated just where
he should look on the scale to see find the computer's intended
landing point. In principle, if he didn't like the spot, he could
pulse the pistol-grip hand controller forward or back or to either
side and, thereby tell the computer to move the target a small amount
in the indicated direction. According to plan, Aldrin was to give
Armstrong an "angle" every few seconds until, at an altitude of
about five hundred feet, the window targeting lost its usefulness
and Armstrong took over complete manual control for the final descent.
However, once Aldrin had given him an initial target angle, Armstrong
realized that, although the site selection team had picked a smooth
patch of ground, the state of the guidance art at the time of Apollo
11 wasn't nearly as refined as it would be for the later missions,
and fate and the computer were taking the LM into a field of boulders
on the northeast shoulder of a crater the size of a football field.
Nowhere on the Moon are craters of that size more than a few kilometers
apart and, for this first landing, the NASA flight engineers were
not yet ready to fine-tune the approach trajectory to much better
than about eight kilometers east or west of the target point and
about two kilometers north or south. The Apollo 11 "landing ellipse"
contains dozens of craters a hundred meters across or more, and
the important point is that the LM had plenty of range so that Armstrong
could avoid even the largest of them.
There was no doubt in Armstrong's mind about landing in the boulder
field. It wasn't essential that he land the LM perfectly upright.
A tilt of up to fifteen degrees would cause no particular problem
with a launch. However, if he hit the engine bell or one of the
landing struts on a large rock, there would be a real chance of
sustaining structural damage. Two minutes after pitchover and about
two minutes prior to the landing, Armstrong took action. He decided
to follow an old maxim: "When in doubt, land long." To do that,
he would have to overfly the crater and land well to the west of
it; and there was clearly no point - nor really much time - to give
the computer enough of an update via the hand controller. The Landing
Point Designator (LPD) was designed for fine tuning and what Armstrong
needed was a big change. So he switched to manual control, pitched
the LM forward, and began to fly it like a helicopter. Within seconds,
he had slowed his rate of descent from about twenty feet per second
down to about three and flew the LM about 1100 feet west beyond
the craters and the boulders
Even with the computers to help, landing a LM was a tricky operation,
one that required countless hours of training in indoor simulators
and in an ungainly "flying bedstead" called - more formally - the
Lunar Landing Training Vehicle. According to Cernan, the LLTV was
actually harder to fly than the LM. It was equipped with a big jet
engine which provided enough thrust to counteract 5/6th of the pull
of Earth's gravity and that big engine - firing more or less straight
down - made the trainer more unstable than the LM. Indeed, during
training, Armstrong had to eject from one of the LLTV's. His was
the second of three trainers that went unstable and crashed and,
as Cernan relates, the trainer he flew in preparation for Apollo
17 was the only survivor of an original fleet of four. The long
hours of training paid off, of course.
While Armstrong flew the LM toward a good landing spot, his attention
was totally focused on the job at hand. Aldrin did virtually all
the talking; and he, too, was all business. He read the computer
output to Armstrong, giving him their altitude, their rate of descent
and their forward speed. Back in Houston, Flight Director Gene Kranz
and other members of the support team in the Mission Control Room
were watching telemetry from the LM. They did not know about the
crater yet - Armstrong wouldn't discuss it until well after the
landing - but it was obvious that the landing was taking longer
than planned. Indeed, with each passing second there was mounting
concern about how much fuel remained. Because of uncertainties in
both the gauges in the tanks and the estimates that could be made
from telemetry data on the engine firing, the amount of time remaining
until the fuel ran out was uncertain by about 20 seconds. If they
got too low, Kranz would have to order an abort.
Drama was the last thing that any one had wanted for the first
landing. The event itself was exciting enough. Finally, Armstrong
found a place that he liked and he began to kill his forward velocity
and let the LM ease down toward the surface. As they came down through
75 feet, Duke radioed that they had sixty seconds of fuel left and,
in the cabin, Aldrin had already seen a warning light that was telling
him the same thing. But they were close now and it was just a matter
of easing themselves down. Armstrong had killed almost all of their
forward velocity and now, as they began to kick up dust with the
engine exhaust, he asked Aldrin to confirm that they were still
moving forward a little. He wanted to land on the surface he could
see in front of them, rather than on ground he couldn't see behind
them. Aldrin gave him the confirmation that he wanted and, eight
seconds later, they saw the contact light. The ten-foot-long probes
that dangled from the landing gear had touched the Moon. A second
or two later they were down and had the engine shut off. Forty seconds
had passed since the sixty-second warning, but they were down.
(Post-mission analysis indicated that they actually had about 45
seconds of fuel left, rather than 20. Nonetheless, it the smallest
margin of all the Apollo landings. Note, also, that, in the interest
of reducing uncertainty, the fuel gauging system was improved for
Apollo 12.)
Despite the drama of the moment and the enormous feelings elation
and relief that they both felt, Armstrong and Aldrin had little
time for anything but getting the LM ready for an immediate departure.
No one expected that they would have to launch right away but, just
in case a problem did develop - say a leak of the high pressure
helium that they would use to pressurize the propellant tanks in
the Ascent Stage, they wanted to be ready. However, despite being
very busy with things in the spacecraft for nearly two hours after
they landed, from time to time they stole glances out the window
and described the scene for the radio audience back on Earth.
Preparing to Go Outside
In all directions, the land was West Texas flat. The circular
horizon was broken here and there by the subtle rims of distant craters.
In the middle distance, Armstrong and Aldrin could see boulders and
ridges, some of the latter perhaps 20 or 30 feet high. Close at hand,
a hodgepodge of craters pockmarked the surface; and there were small
rocks and pebbles scattered everywhere. It was a flat, level site
but, as with Australia's Nullarbor (Latin for "Treeless") Plain, small
variations gave the surroundings a subtle beauty of its own. And,
of course, because this was the very first landing on the Moon, everything
was of enormous interest. However, before Armstrong and Aldrin could
pay much attention to the view or think about going outside themselves,
they had to be sure that they had a healthy spacecraft and that the
navigation computer was properly loaded with the information needed
to get them back to orbit for a rendezvous with Collins. Finally,
two hours after the landing, they and the NASA engineers were satisfied
that the LM was ready to come home and, therefore, that it was safe
to stay for a while.
According to the flight plan, Armstrong and Aldrin were scheduled
to take a five-hour rest break before getting ready to go outside.
However, it came as no surprise when they suggested to Houston that,
after a scheduled hour-long meal, they prepare for what was called,
in the NASA jargon, an EVA - a period of Extravehicular Activity.
Normally, the EVA preps were supposed to take about two hours but,
because this was to be the shortest of the Apollo EVA's no one -except,
perhaps, the waiting, worldwide TV audience - was bothered when
the EVA preps actually took three and a half hours.
One Small Step
Finally, about six and a half hours after the landing, they had
the hatch open and Armstrong crawled out onto the porch - feet first
and on his hands and knees. Moments later he was on the top rung of
the ladder and pulled a lanyard to release a work bench / stowage
area that was attached to the side of the LM. The Modular Equipment
Storage Assembly or MESA was pivoted at the bottom so that, when Armstrong
pulled the lanyard, the MESA swung down into a horizontal position.
The most important piece of gear on it was undoubtedly the black-and-white
TV camera. It was mounted in such a way that, when the MESA swung
down, the camera was pointed directly at the foot of the ladder. For
the astronauts, the landing had been the big moment of the mission.
But, for the waiting world, the big moment was still to come - the
first footstep.
From the bottom rung of the ladder, Armstrong had to make a three-foot
jump down to the footpad - a contingency against a less than gentle
landing that might have compressed and shortened the landing strut.
From the footpad, he had only a couple of inches to step down to
the surface itself. He stood on the pad for a moment or two, testing
the soil with the tip of his boot before he made the epochal "small
step".
The soil was very fine grained and had a powdery appearance and,
once he stepped down, his boot sank perhaps a couple of inches,
making a sharply defined print. Because of the Moon's relatively
weak gravity field (one-sixth as strong as Earth's), Armstrong's
total weight - half astronaut, half suit and backpack - was only
about sixty pounds. Movement wasn't particularly tiring but because
of the dramatic upward-shift in his center of mass caused by the
backpack, he had to lean forward to keep his balance and it took
a few minutes before he could walk comfortably. Just in case he
had to end the EVA suddenly, Armstrong used a long-handed tool called
the Contingency Sampler to scoop up a bit of rock and soil into
a Teflon bag. He then removed the bag from the Sampler, folded it,
and stored it in a shin pocket.
Aldrin joined Armstrong out on the surface about fifteen minutes
later and then, for the next hour and forty minutes, the two of
them examined the LM, moved the TV camera out about 50 feet, deployed
a pair of scientific instruments, and collected more samples. One
important set of questions to be addressed, of course, concerned
the crew's ability to get the work done. If all went well, following
crews could stay longer on the Moon, venture farther from the LM,
and undertake more ambitious sets of tasks. For the first half hour
or so, neither Armstrong nor Aldrin did more than a shuffling walk
as they went about their work and it was planned, after this initial
period of familiarization, for Aldrin to try to take advantage of
the 1/6th gravity and try to run. Starting from near the LM, he
first ran toward the TV camera, rolling from foot to foot in a loping
or, as Jack Schmitt calls it, a cross-country skiing stride. Then
as he turned and ran back toward the LM, he used the same gait again
but twice changed direction by sticking a foot out to the side and
pushing off of it, rather like an American football running back.
Coming back toward the camera for a second time, he tried a kangaroo
hop but decided that it didn't give him as much fore/aft stability
as he got with the loping gait. It looked as though a crew that
ventured a few hundred meters away from their LM would be able to
run back in just a few minutes if the need arose.
In general, the crew of Apollo 11 went about their work with appropriate
caution. However, as with later crews, as time passed, their confidence
grew. Generally, they walked without bounding and, compared with
later crews, their movements seem fairly stiff and restricted. However,
toward the end of the EVA, the TV audience got a glimpse of Armstrong
running back from a brief visit to a crater 60 meters east of the
spacecraft. There was even one moment - a bit earlier in the EVA
when Aldrin was lifting the scientific instruments down from its
storage compartment - when Armstrong appeared to bob down on one
knee, a difficult maneuver in the stiff spacesuit. Clearly, it was
possible to get work done and to move with relative ease. Later
crews would have more time to adapt and, building on the Apollo
11 experience, would do their work with greater and greater confidence.
With only a short time at their disposal, Armstrong and Aldrin
had only a few things they could get done before they had to have
the hatch closed. They raised an American Flag, deployed a solar
wind collector, gathered forty-seven pounds of samples, and carried
a laser reflector and the passive seismometer about twenty meters
south of the LM for deployment. They hammered two, short core tubes
into the soil, took about one hundred color photographs, and, finally,
got themselves and the samples back into the spacecraft. Because
of the restrictions imposed by the pressurized suits, by the shifted
center of mass, by the weak gravitational field, and especially
by the clumsy, pressurized gloves, the work was generally harder
to do than it would have been in a shirtsleeve environment.
Deploying the Scientific Equipment
Compared with later missions, the suite of scientific gear that
Armstrong and Aldrin deployed was quite modest and, as Jack Schmitt
told the story during our review of this Apollo 11 summary, at least
part of the reason was a concern over fuel margins.
"Probably it was spring of '68. The PSAC - the President's Scientific
Advisory Committee which was chaired by Charlie Townes - asked NASA
for a set of briefings that would detail how the first lunar landing
mission would be conducted. And NASA had never done that because
they were concentrating so hard on getting the spacecraft ready
to fly. And it was a very good request; PSAC was right on the money.
Asking questions like that is the way a science advisory committee
can really contribute to the process, and the PSAC forced NASA to
think things through. So what NASA did was assign two astronauts
to each of three phases of the mission: launch to Lunar Orbit Insertion
(LOI), LOI to TEI (TransEarth Insertion), and then the trip home.
And Buzz Aldrin and I were assigned the middle part of that. He
was to do spacecraft stuff in orbit and I was to put together what
we were going to do once we were on the surface. At that time the
only thing NASA really had ever done in any detail was the so-called
design reference mission. In fact, NASA didn't do it; Grumman did
it. And that was a mission with four 4-hour EVA's. And the only
thing that had happened since then was NASA backed off and said
'Well, with the ALSEP (Apollo Lunar Science Experiment Package)
on board and the geology experiment, we'll have two EVA's.'
"There was lots of discussion about it. I mean, at that same time,
some people were saying 'Well, maybe we ought to just have one guy
go out on an umbilical; it's too dangerous.' Slayton wanted a buddy
system -two guys going out with backpacks - and I was supporting
him on that and I got into a lot of arguments. God, the kinds of
things we went through to finally get there. And, at the same time,
Buzz Aldrin was trying to get to be the first guy to go out. (Laughing)
He had me working on some scheme to figure out how in the world
we could justify having him and Armstrong switch places in the LM
after landing. God! Anyway, in putting together the Lunar Surface
EVA Operations Planning Book for the PSAC - which was the first
time anybody tried to do a detailed timeline for two EVA's - it
became increasingly obvious - when you put it in light of the problems
the LM was having in terms of weight and everything - that the chances
of 300 plus pounds of ALSEP flying were pretty small. So, in my
draft charts before the final briefing, I included some issues that
had to be addressed. And one of them was: do we need a contingency
ALSEP? What were the two experiments that you'd like to have on
the Moon if you never got another chance? And, very quickly, it
was obvious what those were. One was the seismometer and one was
the corner reflector. And so I had this on my draft charts.
"We did a dry run with the JSC management before giving it to PSAC.
And, when that chart came up Bill (Wilmot) Hess just went ballistic!
He wouldn't hear of not flying the ALSEP. I mean, the guy just lost
it. And everybody was just sort of staring at him. He was Science
Director and he just couldn't control himself. I don't think he's
ever forgiven me for doing that. But the judgment of Bob Gilruth
and George Low was 'It makes sense, so let's go to work.' Basically,
we had six months - I think it was - to get it ready. It would be
solar powered and lightweight. I don't remember how much it weighed.
And Bill Hess was absolutely convinced - and was right - that, as
soon as the contingency package existed, they'd take the ALSEP off
of Apollo 11. Well, my position was that they were going to do that
anyway and, if you didn't have something, you weren't going to get
anything. God, we went around and around on that. But that's why
Apollo 11 didn't have ALSEP but did have some science experiments."
Weight limitations were certainly one reason why Apollo 11 flew
with only a few pieces of scientific gear. Another was the simple
fact that, on this first landing, it was unlikely that NASA management
would have approved an EVA long enough to allow the astronauts to
deploy a complete ALSEP. On the Apollos 12 and 14, the ALSEP deployment
typically took most of the first four-hour EVA and, as the first
crew to do a lunar EVA, it seems unlikely that Armstrong and Aldrin
would have been allow to stay out that long.
Closing Out the EVA
As Cernan suggests in his Apollo 17 commentary, there is always
a best way to get a job done under lunar conditions; and, although
Armstrong and Aldrin didn't have time to discover many of the tricks
and didn't have the experiences of prior crews to guide them, the
EVA went smoothly. That success can be ascribed readily to forethought,
to careful training, and to a measure of justified caution on this
first lunar visit. The only significant problem that they encountered
came when Aldrin tried to drive the core tubes into the soil. Despite
hammering hard enough to actually dent an extension handle attached
to the top of the tubes, on both attempts Aldrin only managed to drive
the tubes about 8 to 9 inches into the ground. In hindsight, the cause
of Buzz's troubles was the fact that, more than a few inches below
the surface, lunar soil is almost perfectly compacted, a circumstance
that had not been anticipated. The core tubes were of a fairly standard
design which included an internal bevel to provide some compaction
of the entering soil so that it wouldn't promptly fall out. Because
the lunar soil was already very compact, it simply couldn't be forced
into a standard tube and it was impossible for Buzz to drive one more
than a few inches deep.
What was probably the least efficient work that either Armstrong
or Aldrin did came during the final minutes when Armstrong used
a piece of equipment called the Lunar Equipment Conveyor or LEC
to get the rock box up to Aldrin in the cabin. Essentially, it was
a clothesline. After Aldrin hooked the LEC to a pulley in the cabin,
Armstrong hooked the rock box to the LEC, backed away from the LM
to make the line taut, and then pulled hand-over-hand as the box
bounced its way up to Aldrin. It was hard work. At the start of
the EVA, Armstrong's heart rate had been about 120 beats per minute
and it had declined more or less steadily toward a low of about
80 as he took pictures at the rim of the crater east of the spacecraft.
With time running short, he began a hurried collection of rocks
and soil and his heart rate climbed to the 120-140 beat range. And
then, while he was using the LEC, his heart rate shot up to 160
beats per minute and Houston had to call for a short rest. Other
Apollo Commanders didn't have to work quite so hard when they were
using the LEC. The excitement of the moment and the rush of collecting
the bulk sample surely were contributing factors in Armstrong's
case. But the LEC was an inefficient tool and, beginning with Apollo
14, the astronauts started carrying at least some of their gear
up to the cabin by hand. The 16 and 17 crews did away with the clothesline
LEC entirely - having decided that it was more trouble than it was
worth - and hand carried everything except a bag containing their
camera. That bag they raised and lowered with a hook and lanyard,
a humble rope that somehow managed to inherit the LEC's name.
Two hours and thirty one minutes after they first opened the hatch,
Armstrong and Aldrin reported it closed again. There were still
five hours to go before Houston said "Good Night" and there was
still plenty to do. There were samples to stow, gear to be jettisoned,
and a long list of housekeeping tasks to be taken care of before
they could have a scheduled rest period.
They slept in their suits - or tried to - with Aldrin curled up
on the floor and Armstrong propped up on the ascent engine cover
in the rear of the cabin. The rest period was, they said, "almost
a complete loss." They were bothered by spacecraft noises and by
sunlight leaking around the edges of the window shades and in through
the sextant. They were cold and damp in the suits and, of course,
they were really too excited to sleep. Not until Apollo 15 did anyone
really get any sleep on the Moon. From Apollo 12 onward, the crews
had a heater to help with the cabin temperature and hammocks they
could lie in. However, it wasn't until Apollo 15 that the lunar
stays were long enough - and the astronauts and mission planners
had confidence enough - that the crews got out of their suits during
the rest periods and, with the help of earplugs to cut down on the
noise, really got some sleep. Aldrin may have gotten two hours of
fitful sleep. Armstrong got none at all.
For seven hours Houston left them alone with their
thoughts. Then it was time to wake up, have a quick breakfast, and
get ready for the launch, the rendezvous with Collins, and the heroes'
welcome awaiting them at home. If, from a practical point of view,
Apollo 11 was a demonstration flight, a point of departure for the
more sophisticated missions that would follow, it was still the
one for the history books. The other crews would work in relative
obscurity, stepping briefly into the spotlight but without leaving
so lasting a public impression. There would never be anything quite
like making that first footprint on another world but then, too,
there was still a long way to go before humanity could claim to
be more than temporary visitors to the Moon.
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