Moonshot: The Inside Story of Mankind's Greatest Adventure - Dan Parry (2009)

Chapter 14. A WALK ON THE MOON

By the time Apollo 11 was ready to launch, few people still believed that heavy objects settling on the Moon would sink into the dust. Yet in preparing to step on to the unfamiliar surface, Neil took the precaution of securing himself to the LM.1 Before sliding through the hatch, he set up the lunar equipment conveyor (LEC), a strap and pulley system that would allow a camera, and other awkward items, to be hoisted to and from the cabin. With one end of the LEC secured to the cockpit and the other to his suit, Neil faced the rear of the cabin. Kneeling down, he pushed his feet out through the hatch until he found the porch at the top of the ladder. After testing his ability to pull himself back inside, Armstrong got down again and began to slide out backwards. Guided by comments from Aldrin, he moved slowly to avoid snagging his PLSS.

Aldrin: 'OK. You're not quite squared away. Roll right a little. Now you're even.'

Armstrong: 'OK, that's OK.'

Aldrin: 'That's good. You've got plenty of room to your left.'

Armstrong: 'How am I doing?'

Aldrin: 'You're doing fine.'

Aldrin: 'OK. You want this bag?'

Once outside on the porch, the first thing Neil did was throw out the bag, containing empty food trays and other equipment which couldn't be used again. After this he pulled a handle on the left of the porch which opened a compartment built into the hull of the LM beneath Buzz's window. Known as the MESA (modular equipment stowage assembly), it contained the crew's sampling tools and rock-boxes. As its door hinged down it exposed a TV camera fastened to its inside surface and aimed at the foot of the ladder. By closing a circuit breaker on the instrument panel Buzz sent power to the camera, allowing a snowy picture of Neil to be transmitted back to Earth.

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The decision to include television cameras on the mission had been controversial from the start. Transmitting and receiving live pictures from the Moon created complications on the ground and required equipment to be added to a spacecraft that was already severely restricted in the weight it could carry. In early 1969 George Low asked Chris Kraft to look into the subject. Kraft was anxious to see 'those first steps live' and tried to do what he could to build the necessary support.2 Gene Kranz's unpredictable communications officer Ed Fendell was given the task of looking at the question in detail, with a view to producing a favourable report. 'I should have given them better direction,' Kraft later fumed.3 At a meeting attended by almost everybody with an interest in the subject, Fendell finished his report with the thought that there was no reason to have television on the Moon. Kraft erupted. 'I can't believe what I'm hearing,' he shouted above a clamour of raised voices. 'We've been looking forward to this flight – not just us, but the American taxpayers and in fact the whole world – since Kennedy put the challenge to us.'4 With the old hands leading the way, the pro-TV camp quickly gathered force and the room soon came round to their way of thinking. Once Armstrong and the crew gave them their support the matter was officially settled. But privately, reservations remained. Referring to it as 'a bloody nuisance of an afterthought', Michael Collins wrote that 'we simply didn't have time to fool around with it'.5

There wasn't time to develop a colour camera for use on the lunar surface; instead, the LM was equipped with a Westinghouse slow-scan model that shot ten frames a second in black and white. It was fitted with a bayonet mount, designed to allow the lens to be changed by an astronaut wearing a pressure- suit. Television pictures, transmitted via the LM, would be received by the Manned Space Flight Network tracking stations at Honeysuckle Creek in eastern Australia and Goldstone Lake, California. Due to the crew's four-hour rest, as scheduled in the flight-plan, the EVA would begin twenty minutes after the Moon had set at Goldstone. This meant NASA would be principally relying on the facilities in Australia. Honeysuckle was supported by the Parkes Radio Telescope in central New South Wales, which, like Goldstone, was equipped with a giant 210-foot antenna.

In eastern Australia the landing occurred at 6:17am local time on the morning of 21 July. Although it would be seven hours before the Moon was high enough to be seen from Parkes, this was anticipated in the flight-plan.6 So when the crew decided to drop their rest period, the Parkes technicians feared the whole thing would be over before the Moon had risen above their part of the world. They would have to give way to Goldstone. But as the preparations aboard the LM dragged on, hope returned to Parkes. By the time Neil finally emerged from the hatch, six hours and 22 minutes after the landing, the Moon was just beginning to rise above New South Wales.7 Yet now the Parkes technicians faced a new problem. Parkes scientist John Sarkissian recalled that the winds were so high the huge dish was forced to operate well outside safety limits.8

The signal from Parkes was sent to Sydney, and there it was converted into a format suitable for domestic television before being distributed to the Australian TV networks. At the same time, it was relayed to a communications satellite over the Pacific and then passed to Houston, where a six-second delay was added in case anything happened to the astronauts. The pictures were then ready to be released to the rest of the world. Parkes, Honeysuckle and Goldstone received television from the Moon simultaneously and Houston briefly distributed the picture from Goldstone and Honeysuckle before deciding for technical reasons to stay with Parkes for the rest of the EVA.9

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Before a television audience of 600 million people, a fifth of the human population, Neil slowly climbed down the ladder on the leading leg of the LM.10 The ladder stopped three feet above the ground to prevent it being bent by protruding rocks. In Mission Control the TV picture was projected on to a screen on the front wall, creating a ripple of excitement among Cliff Charlesworth's team of flight controllers.

Mission Control: 'OK. Neil, we can see you coming down the ladder now.'

Armstrong: 'OK. I just checked getting back up to that first step, Buzz. It's...the strut isn't collapsed too far, but it's adequate to get back up.'

Mission Control: 'Roger. We copy.'

Armstrong: 'Takes a pretty good little jump.'

Jumping down from the last rung, Neil found himself standing in the landing pad. Before he went any further he rehearsed the jump back on to the ladder to be sure it wouldn't be a problem later. He then jumped back down into the landing pad.

Armstrong: 'I'm at the foot of the ladder. The LM foot-pads are only depressed in the surface about one or two inches, although the surface appears to be very, very fine grained, as you get close to it. It's almost like a powder. Ground mass is very fine.'

Armstrong: 'I'm going to step off the LM now.'

Still tethered to the cabin by the LEC, Armstrong stepped off the landing pad, placing his left foot on the dust and tentatively shifting his weight. To Buzz it seemed like a 'small eternity' before he heard Neil say anything.11

Armstrong: 'That's one small step for man; one giant leap for mankind.'

In the years after the mission, Neil's apparently tautological historic words have become the subject of much debate. Armstrong later said he intended to say 'one small step for a man' and believed he had done so. Yet, despite extended efforts by some to prove the contrary, the 'a' appears to be missing from the sound recording of Neil's transmission. Nevertheless, for most people his message was clear.12

Armstrong: 'The surface is fine and powdery. I can kick it up loosely with my toe. It does adhere in fine layers, like powdered charcoal, to the sole and sides of my boots. I only go in a small fraction of an inch, maybe an eighth of an inch, but I can see the footprints of my boots and the treads in the fine, sandy particles.'

Having put both feet on the surface, for the first time Neil let go of the ladder and disconnected himself from the LEC tether. In front of him stretched an arid desert, bathed in bright daylight beneath a dark night sky. The silent wastes appeared to be tan, but their colour dissolved to shades of grey the closer he looked towards areas of shadow. Armstrong thought the ground beside his feet was a charcoal grey, 'the colour of a lead pencil'.13 Close to the spacecraft, light grey dust lay scattered across small rocks that had been thrown aside during the landing. Further away were two features that could be described as low hills, while several hundred feet to the right of the LM lay a boulder field. Without high ground or a hazy atmosphere to obscure his view Neil could see as far as the horizon, which curved away in all directions. For 360 degrees there was nothing but dust, rocks and craters. Only Eagle offered any relief from the stark landscape, its golden foil and silver-coloured components reflecting the dazzling light like a gleaming beacon of precious metal. Bathed in sunshine, the LM cast depths of shadow of breathtaking blackness.

Armstrong: 'There seems to be no difficulty in moving around - as we suspected. It's even perhaps easier than the simulations of one-sixth g that we performed in the various simulations on the ground. It's absolutely no trouble to walk around.'

Armstrong: 'OK. The descent engine did not leave a crater of any size. It has about one-foot clearance on the ground. We're essentially on a very level place here. I can see some evidence of rays emanating from the descent engine, but a very insignificant amount.'

The airy black and white TV pictures gave Neil a ghostlike appearance, and at first it was hard to make out what was happening. In the Armstrong household, six-year-old Mark heard his father describe the lunar dust, and asked, 'How come I can't see him?'14 But to the technicians at Parkes, the controllers in Houston and fascinated TV viewers around the world, an astronaut was definitely moving about on the surface. The Moon was now within man's reach as much as next-door's back yard. Joan Aldrin clapped her hands and cried, 'I can't believe this.'15

While the TV pictures might have been a little murky, Neil and Buzz were equipped with a modified Hasselblad 500EL camera, capable of taking pinpoint photographs on 70mm film. Buzz used the LEC to lower the camera down to the surface, and once he had retrieved it Neil secured it to a mount on the remote control unit on his chest.

Armstrong: 'I'll step out and take some of my first pictures here.'

Mission Control: 'Roger. Neil, we're reading you loud and clear. We see you getting some pictures and the contingency sample.'

After taking a series of panoramic pictures while standing at the bottom of the ladder, Armstrong left the shadow of the LM and walked ten feet over to a sunlit area. Here, within the view of the 16mm film camera in Buzz's window, Neil took a tool from a pocket on his left leg and collected an initial sample of dust. He deposited the material into a bag, which he then returned to his pocket. If the EVA ended early, Armstrong still hoped to be able to bring home a small selection of material.

Armstrong: 'This is very interesting. It's a very soft surface, but here and there where I plug with the contingency sample collector, I run into a very hard surface. But it appears to be a very cohesive material of the same sort. I'll try to get a rock in here. Just a couple.'

Armstrong: 'It has a stark beauty all its own. It's like much of the high desert of the United States. It's different, but it's very pretty out here. Be advised that a lot of the rock samples out here - the hard rock samples – have what appear to be vesicles [small cavities] in the surface. Also, I am looking at one now that appears to have some sort of phenocrysts [crystals].'

Mission Control: 'Houston. Roger. Out.'

Aldrin: 'OK. Are you ready for me to come out?'

Armstrong: 'Yeah. Just stand by a second. I'll move this [the LEC strap] over the handrail. OK.'

Fifteen minutes after Neil arrived on the surface, Buzz emerged from the hatch, guided and photographed by Armstrong.

Aldrin: 'OK. Now I want to back up and partially close the hatch. Making sure not to lock it on my way out.'

Armstrong: 'A particularly good thought.'

As Buzz paused on the ladder, television viewers saw a man apparently taking time to reflect. In fact Buzz was relieving himself before jumping down to the landing pad. 'The whole world was watching, but I was the only one who knew what they were really witnessing,' he later remarked.16 Still holding on to the ladder, Aldrin marvelled at the emptiness stretching before him.

Aldrin: 'Beautiful view!'

Armstrong: 'Isn't that something! Magnificent sight out here.'

Aldrin: 'Magnificent desolation.'

'I felt buoyant,' Buzz wrote, 'and was full of goose pimples.'17 He was intrigued by the lunar dust; comparing it to sand on a beach he found it notably different. When kicking grains of sand, some quickly fall down while others scatter a little further, but Buzz discovered that in doing the same thing on the Moon every grain travelled the same distance. Both men found that as fine as the grains of dust were they had a tendency to stick together, forming clods of material that crumpled under their boots.18

Together with his suit and backpack, on Earth Buzz weighed a total of 360lb. On the Moon this was cut to 60lb. Taking his first few steps away from the LM, Aldrin found that it was easier to walk if he leant forward a little. With practice, he was able to move around as comfortably as if he were at home. When Buzz tried to run he felt himself to be much lighter, and realised that if he were to stop suddenly he would topple over. Instead he had to wind down slowly, being careful to avoid rocks near the LM which were slippery with dust. Neil tried jumping a few times but found that the PLSS had a tendency to make him tip over backwards, and after nearly falling he decided 'that was enough of that'.19 In the piercing sunshine, Buzz thought that Neil's pressure-suit gleamed 'like no white I had seen before', making Armstrong stand out on the surface almost as brightly as the LM.20

Neil found that the suit was largely comfortable and allowed him to move around freely – with the exception of bending down to pick up things from the surface. This had already been established during practice sessions at home, influencing the design of the soil-sample tools. The suits also prevented the men kneeling, and this fact, together with the difficulty of retrieving things with their hands, led to concerns about dropping things. Objects could be scooped up using tools but this was a time-consuming process. 'The suit was cumbersome and bulky and not really easy to operate,' Neil recalled, 'but on the whole, it performed remarkably well. When you think that the surface temperature was something north of 100 centigrade, in terms of the [air] flow and the cooling, it was really doing an excellent job, and allowed us to really do most of the things we planned to do – although perhaps not as quickly as we would have liked to do them.'21

After familiarising himself with the surface and the suit, Aldrin watched Armstrong remove the cover of the commemorative plaque that was secured between the rungs of the ladder. Since the ladder was attached to the descent stage, the plaque would remain on the Moon.

Armstrong: 'For those who haven't read the plaque, we'll read the plaque that's on the front landing gear of this LM. First there's two hemispheres, one showing each of the two hemispheres of the Earth. Underneath it says "Here Men from the planet Earth first set foot upon the Moon, July 1969 A.D. We came in peace for all mankind." It has the crew members' signatures and the signature of the President of the United States.'

Aldrin later said, 'This was one place where I felt signing "Buzz" was too informal'.22

Neil then took the TV camera from the MESA and after changing its lens he carried it to a point some 60 feet away to the right of the LM, where it could cover a wider region of the surface. While looking for a suitable spot, something in a crater caught his eye. This was later thought to be a glassy material produced during the intense heat and shock of a high-velocity impact. 'We were supposedly in a nondescript area,' Aldrin recalled, 'but there was far more to investigate than we could ever hope to cover. We didn't even scratch the surface.'23 The camera's white cable, leading back to the LM, retained a spiral kink that left it sticking up above the surface. Once it became dirty it was hard to see. Neil caught his foot in it and needed help from Buzz to untangle himself.

While Armstrong was working on the camera, Aldrin set up the solar wind collector about ten feet to the right of the LM. Looking like a narrow flag, one foot wide and four and a half feet tall, the SWC was made of thin aluminium foil. Deployed facing the Sun, it was designed to capture particles of helium, neon and argon that were found in the solar wind.

After setting up a table at the MESA, Buzz helped Neil remove the US flag from its case beneath the ladder. They carried it back towards the TV camera and chose a spot around 15 feet from the LM. The flag was designed to hang from a telescopic arm that extended perpendicularly from the pole. But despite pulling as hard as they dared, the arm wouldn't properly extend and Armstrong and Aldrin feared an imminent public relations disaster.24 The flag was left distinctly ruffled – as were conspiracy theorists, who later wanted to know why it looked as if it were being blown by the wind. After coping with this problem, the flag still threatened to upstage the men when it refused to be pushed into the ground. The dust on the surface was relatively soft but deeper down it became hard to penetrate. Inside his gloves Neil's hands were sweating and he found it difficult to grip the staff and drive it into the soil.25 At first the flag defied attempts to make it stand upright but eventually Armstrong forced it into the dust by about seven inches, far enough to prevent it toppling over live on television.

In the meantime Collins, now on his eighteenth orbit, returned from his enforced silence and began to pass across the near side once again.

Collins: 'Houston, Columbia on the high gain. Over.'

Mission Control: 'Columbia, this is Houston. Reading you loud and clear. Over.'

Collins: 'Yeah. Reading you loud and clear. How's it going?'

Mission Control: 'Roger. The EVA is progressing beautifully. I believe they are setting up the flag now.'

Collins: 'Great!'

Mission Control: 'I guess you're about the only person around that doesn't have TV coverage of the scene.'

Collins: 'That's all right. I don't mind a bit. How is the quality of the TV?'

Mission Control: 'Oh, it's beautiful, Mike. It really is.'

Neil took a picture of Buzz saluting the flag and then he went back to the MESA to begin collecting more material from the surface.

Mission Control: 'Tranquility Base, this is Houston ... we'd like to get both of you in the field-of-view of the camera for a minute. Neil and Buzz, the President of the United States is in his office now and would like to say a few words to you. Over.'

Armstrong: 'That would be an honour.'

Mission Control: 'All right. Go ahead, Mr President. This is Houston. Out.'

Nixon: 'Hello, Neil and Buzz. I'm talking to you by telephone from the Oval Room at the White House, and this certainly has to be the most historic telephone call ever made. I just can't tell you how proud we all are of what you [unclear] For every American, this has to be the proudest day of our lives. And for people all over the world, I am sure they, too, join with Americans in recognising what an immense feat this is. Because of what you have done, the heavens have become a part of man's world. And as you talk to us from the Sea of Tranquility, it inspires us to redouble our efforts to bring peace and tranquility to Earth. For one priceless moment in the whole history of man, all the people on this Earth are truly one; one in their pride in what you have done, and one in our prayers that you will return safely to Earth.'

Armstrong: 'Thank you, Mr President. It's a great honour and privilege for us to be here representing not only the United States but men of peace of all nations, and with interests and the curiosity and with the vision for the future. It's an honour for us to be able to participate here today.'

Nixon: 'And thank you very much and I look forward, all of us look forward to seeing you on the Hornet on Thursday.'

Armstrong : 'I look forward to that very much, sir.'

Armstrong later told Aldrin that he had known the president might call. Buzz, who had had no such knowledge, wrote that the experience made him feel awkward. He felt he ought to have made some profound comment, but without wanting to intrude on the conversation he took what seemed to be the next best alternative and remained silent.26

After the call, the astronauts went back to the MESA where Buzz picked up the Hasselblad camera left there by Neil. While Armstrong collected samples of rocks, Buzz took pictures of the impression his boots made in the dust. As he set up collection bags and the sample return containers on the table, Neil found he was working in shadow. He wanted to avoid collecting material that had been contaminated by the exhaust from the descent engine, and in looking for an undisturbed sunlit area he walked back towards the solar wind collector. He tried to scoop up as many different types of rocks as he could before taking them back to the table and dropping them into a bag. Making around ten trips to this spot, Armstrong repeatedly crossed back and forth from harsh sunlight into the LM's stark shadow and he found his eyes were sometimes slow to adjust. During training it had been suggested that he could possibly twist the LM immediately before landing, to make sure the MESA was in sunlight. But Armstrong remembered that 'I was very reluctant to do any fancy manoeuvring on the first lunar touchdown'.27

Taking the camera from Buzz, Neil photographed the sample area before taking a full-frontal picture of Aldrin. Buzz, his gold visor pulled down, stands with his left arm raised as he prepares to read from the checklist on his glove, in what has since become one of the most iconic photographs of all time. Neil then gave the Hasselblad back to Buzz before taking from the MESA a stereoscopic camera, designed to snap close-up images of the lunar dust. It was a late addition to the flight, and Neil found it tricky to operate.28 Now half an hour behind their timeline, Armstrong tried the stereoscopic camera while Buzz removed the seismometer and the laser reflector from the LM's scientific equipment bay.

Aldrin: 'OK; have you got us a good area picked out?'

Armstrong: 'Well, I think right out on that rise out there is probably as good as any.'

Buzz set up the seismometer about 50 feet to the left of the LM, placing it behind a large rock to shield it from the effects of lift-off. While he made sure it was level and that the solar panels were properly deployed, Neil set up the reflector. Made up of many finely machined quartz corners, the device would allow the measurement of small changes in the motion of the Moon or the Earth.

Mission Control: 'Neil, this is Houston. Over.'

Armstrong: 'Go ahead, Houston.'

Mission Control: 'Roger. We've been looking at your consumables, and you're in good shape. Subject to your concurrence, we'd like to extend the duration of the EVA 1-5 [i.e. 15] minutes from nominal. We will still give Buzz a hack at 10 minutes prior, for heading in. Your current elapsed time is 2 [hours] plus 12 [minutes]. Over.'

Armstrong: 'OK. That sounds fine.'

After setting up the experiments, their next task was to take a documented sample of the surface. This involved Buzz taking two core samples from an area that Neil would then closely photograph. While Aldrin prepared the tubes, Armstrong decided to break from the timeline and dash back to the 80-foot crater they had flown over just before landing. He knew this would be his best opportunity to take a look beneath the surface. The crater lay nearly 200 feet away to the east of the spacecraft, towards the Sun, and in the true spirit of exploration Neil freely ran across the ground, carrying the Hasselblad and the stereoscopic camera. He found that the crater was 20 feet deep, and after peering inside he spent a minute taking pictures.

Researchers Joe O'Dea and Thomas Schwagmeier have shown that if Neil had been standing on the penalty spot in front of the right-hand goal on a soccer pitch, the LM would be just in front and to the right of the other penalty spot.29 The TV camera would be in the far right-hand corner, the flag would be between the camera and the LM, and the seismic and LRRR experiments would be over towards the left-hand boundary line.

Neil ran back to the LM just as Buzz was preparing to push in the first core sample, near the solar wind collector. Both Armstrong and Aldrin described attempts to run as more of a lope – somewhere between a run and a walk, where both feet would be off the ground at the same time. Finding that their actual 'foot motion' was quite slow, Neil said that while loping he would find himself 'waiting to come down' in between strides.30 At home in Houston, Pat Collins exclaimed, 'Look at Neil move. He looks like he's dancing – that's the kangaroo hop.' Joan Aldrin thought that Buzz too was doing a form of kangaroo bounce and she asked, 'How can you be serious about what you're doing when you're doing that?' For her, the moonwalk had an unreal quality about it, as if she were watching a Disney cartoon. In the Armstrong household, there was some debate as to who was saying what since Neil and Buzz sometimes sounded alike. Ricky suggested his father was easy to recognise since 'he always says uhhh'.31

Taking two core tube samples, Aldrin needed a hammer to drive them into the ground. Nearby, Neil used a pair of longhandled tongs to retrieve any unusual examples of rocks he could find. He dropped them into a collection bag which was then put into one of the sample return containers. Hammering as hard as he could, Buzz found it difficult to force the tubes into the ground. After retrieving them, he then took down the solar wind experiment, rolled it up and placed it back in its container. This was also put into a sample return container, then both were sealed.32

Mission Control: 'Buzz, this is Houston. It's about time for you to start your EVA close-out activities.'

Aldrin: 'Roger. That's in progress.'

Grabbing the magazine from the stereoscopic camera, Buzz put it in a pocket and started up the ladder, which he found was slippery now that his boots were covered in dust. Neil collected the magazine from the Hasselblad, attached it to the first rockbox, then secured both to the LEC strap so that he could haul them up to the cabin. Halfway up, the magazine fell off. Neil leant on the ladder, picked it up and attached it to the second rock-box while Buzz pulled the first into the cockpit. Neil then attached the magazine and the second box to the LEC. Coming at the end of the EVA, this was one of the most demanding moments during the walk on the surface. 'I worked real hard at a high workload,' Neil recalled.33

Armstrong: 'OK. I've got one side [of the LEC] hooked up to the second box and I've got the film pack on.'

Aldrin: 'OK. Good.'

Armstrong: 'Boy, that filth from on the LEC is kind of falling over me while I'm doing this.'

By the time they got the second box into the cabin everything was caked with dust, including the LEC. 'We all looked like chimney sweeps,' Armstrong later remarked.34 Neil asked Buzz whether he had remembered to leave the Apollo 1 badge and the two Russian medals on the surface. They had imagined improvising some form of ceremony but Buzz described it more as an 'afterthought'.35 Taking a pouch containing the items from his pocket, he threw it down on to the ground. Neil then jumped on to the ladder and climbed back into the spacecraft, once again guided by Buzz.

Locking the hatch shut at 12.09am, they completed their post-EVA checklist before re-pressurising the cabin. Both felt a little disappointed that they had barely succeeded in getting everything done. After removing their helmets, they discovered a strange smell which Neil described as 'wet ashes' and Buzz as slightly 'metallic'.36 This smell was later noticed by other astronauts on subsequent lunar missions, one describing it as 'spent gunpowder'.37

Meanwhile, aboard Columbia, Michael, on his nineteenth orbit of the Moon, was just coming back into radio contact with Houston. He had taken photos of the surface but still hadn't located Tranquility Base.

Mission Control: 'ColumbiaColumbia. This is Houston. Over.'

Collins: 'Roger, Columbia on [omni antenna] Charlie. How do you read?'

Mission Control: 'Roger, Columbia. This is Houston. Reading you loud and clear on Omni Charlie. The crew of Tranquility Base is back inside their base, repressurised, and they're in the process of doffing the PLSSs. Everything went beautifully. Over.'

Collins: 'Hallelujah.'

Aboard Eagle, Neil and Buzz were collecting the items they wouldn't be needing again, and dumping them into a bag. This would be jettisoned, along with the backpacks, in an attempt to save as much weight as possible. The Hasselblad camera had already been abandoned on the surface. Using a second camera, Buzz took a picture of a very relieved-looking Neil, then looked back at the flag and at the boulder field beyond it.38 The rocks appeared to be relatively close and the flag seemed to be right outside the window, but he knew that they hadn't got anywhere near the boulders and the flag was 15 feet away. With all available space now taken up by the bubble helmets, LEVAs, PLSSs, camera magazines and rock-boxes, the men tried to find space to eat. Armstrong later said that 'With all that stuff in the cockpit, there's really no place left for people to relax.'39 They then read through a checklist of switch positions, and in doing so Buzz noticed what at first glance appeared to be a serious problem.

Aldrin: 'Houston, Tranquility. Do you have a way of showing the configuration of the engine arm circuit breaker? Over. The reason I'm asking is because the end of it appears to be broken off. I think we can push it back in again. I'm not sure we could pull it out if we pushed it in, though. Over.'

While wearing his PLSS, at some point Buzz had knocked off the switch that would send electrical power to the ascent engine - on which they were depending to get home. 'The little plastic pin simply wasn't there,' Buzz wrote.40

Nearly a minute after Aldrin reported the problem, Houston responded.

Mission Control: 'Tranquility Base, this is Houston. Our telemetry shows the engine arm circuit breaker in the open position at the present time. We want you to leave it open until it is nominally scheduled to be pushed in, which is later on. Over.'

The crew's next task was to depressurise the cabin in order to open the hatch and eject the backpacks and the bag of rubbish. Before they began, for the first time in the mission Deke Slayton came directly on the radio.

Slayton: 'Tranquility Base, Houston.'

Armstrong: 'Go ahead. Tranquility Base here.'

Slayton: 'Roger. Just want to let you guys know that, since you're an hour and a half over your timeline and we're all taking a day off tomorrow, we're going to leave you. See you later.'

Armstrong: 'I don't blame you a bit.'

Slayton: 'That's a real great day, guys. I really enjoyed it.'

Armstrong: 'Thank you. You couldn't have enjoyed it as much as we did.'

Slayton: 'Roger.'

Aldrin: 'It was great.'

Slayton: 'Sure wish you'd hurry up and get that trash out of there, though.'

Armstrong: 'Yes. We're just about to do it.'

Slayton: 'OK.'

In depressurising the cabin, this time they used a second valve to speed up the process, and with their suits connected to the LM's life-support system they opened the hatch. Neil threw the two backpacks down the ladder, along with their over-boots and the bag containing food trays and other litter.

Mission Control: 'Tranquility. We observed your equipment jettison on the TV, and the passive seismic experiment recorded shocks when each PLSS hit the surface. Over.'

Armstrong: 'You can't get away with anything any more, can you?'

Armstrong and Aldrin had now been awake for more than 21 hours, and with their last task of the day completed, at 3.23am Houston bid them goodnight. Although filthy with dust, the cockpit was tidier and there was now room to sleep. Settling down for the seven-hour rest period, Buzz lay on the floor while Neil sat on the ascent engine cover, his feet suspended by a cable lashed above the instruments. They kept their helmets and gloves on, hoping that this would shut out some of the whirring noise from the life-support system.41 But as the temperature dropped, both men found it hard to doze.

On Earth, Pat Collins was also finding it hard to sleep, and in the small hours of the morning she strolled outside to gaze up at the Moon.42 In a Vietnamese prison camp, air force pilot Sam Johnson – an old friend of Aldrin's – approached one of the guards and, pointing to the Moon, said, 'That's ours now.'43