Category The First Men on the Moon

RETRIEVING EAGLE

Immediately after the TLI manoeuvre, the S-IVB adopted an orientation calculated to yield favourable illumination for the separation of the CSM and its subsequent transposition, docking and extraction (TD&E) of the LM. Armstrong yielded the left-hand couch to Collins who, as CMP, had trained for this delicate operation. The reaction control system (RCS) comprised four units at 90-degree intervals on the side of the service module, each with a cluster of four rocket thrusters that could be fired separately or in various combinations to control roll, pitch and yaw motions. During the climb through the atmosphere, the conical adapter mounted on top the S-IVB was allowed to vent to ensure that there would be no sudden release of air when the spacecraft separated.

“You’re Go for separation,” called Bruce McCandless, 3 hours 15 minutes into the mission.

After using the left-hand translational controller to start the aft-facing thrusters, Collins threw a switch to detonate pyrotechnic charges around the rear rim of the service module to detach that module from the adapter. Once a display indicated that he was moving at about 1 foot per second, he ceased to thrust. Meanwhile, the four panels of the adapter hinged open like petals and then detached to drift away. After 15 seconds, he used the right-hand rotational controller to initiate a 2-degree-per-second pitch motion. When so instructed, the digital autopilot was to maintain this angular rate but, to his frustration, it cancelled the rotation and adopted a fixed attitude. He had to repeat the procedure several times before the autopilot accepted the rotation. In consequence, the rotation used rather more propellant than planned. The issue was later determined to be procedural in nature. Once the spacecraft was facing the S-IVB, Collins terminated the rotation and fired the aft-facing thrusters again, this time to halt 100 feet out, whereupon he fired them a third time in order to move back in.

“I hope you’re getting some pictures, Buzz,’’ Armstrong said.

“I’ve got the 16-millimetre going at 16 frames per second,’’ confirmed Aldrin, referring to the Maurer camera he had mounted in window 4. The LM was clearly visible, supported within the annular ring near the base of the adapter by fixtures on its folded legs.

“Be sure that your RCS is working,” Armstrong prompted Collins, to confirm that the forward-facing thrusters to be used for braking were functional, because if they failed the CSM would smash into the LM. When Collins did so, he noted that the efflux rippled the aluminium thermal shielding of the ascent stage, and hoped he wouldn’t damage it.

The extended probe on the apex of the spacecraft was not visible through the small forward-facing window, but Collins did not need to see it as there was a ‘stand off target on the roof of the LM which, when correctly viewed, meant that the probe was centred on the conical drogue. With the Sun over his shoulder, the roof of the LM was nicely illuminated. In easing the probe into the drogue, Collins was conscious that his vehicle had a mass of 65,000 pounds, and that the 33,000-pound LM was attached to the ‘dead weight’ of the spent S-IVB. As the probe penetrated the socket at the apex of the cone, three small capture latches around the tip of the probe automatically engaged for a ‘soft docking’. When he was sure that the vehicles were lined up, Collins threw a switch and a discharge of nitrogen gas pneumatically retracted the probe, in the process drawing the two collars together and triggering 12 spring-loaded latches that established a rigid connection, or ‘hard docking’.

Although the docking was accomplished, Collins was dissatisfied. ‘‘That wasn’t the smoothest docking I’ve ever done.’’

‘‘Well, it felt good from here,’’ Armstrong complimented.

‘‘I mean the gas consumption,” explained Collins. He had used rather more fuel during the transposition manoeuvre than expected.[19]

While manoeuvring, the quality of signal using the omnidirectional antennas had degraded to the point at which communication became impractical. Aldrin operated the controls to slew the high-gain antenna mounted on a boom on the rear of the service module to point its beam towards Earth to restore communications; once locked on, the system would steer itself to maintain maximum signal strength as the line of sight evolved.

The 30-inch-diameter tunnel to the LM ran through the apex of the command module. As per the plan, an open valve in the LM’s overhead hatch had allowed its cabin to vent. Having already raised the pressure in the command module, Collins opened a valve to allow oxygen to pressurise the tunnel, and thence the LM. On opening his hatch, he noted an odour reminiscent of charred electrical insulation, but all the exposed wiring in the tunnel appeared to be factory fresh and he pressed on with his checklist, jiggling each of the docking latches by hand to confirm that it was properly engaged.

In 1958 America’s first satellite, Explorer 1, discovered that there is an intense belt of charged-particle radiation present within the Earth’s magnetic field. In fact, as subsequent satellites revealed, there is an inner belt of high-energy protons and an outer belt of electrons. These ‘radiation belts’ were named after the scientist who

supplied the instrument that made the initial discovery – James van Allen of Iowa University. The proton belt would pose a severe health risk to any astronaut unwise enough to linger within it, but fortunately it was concentrated above the equatorial zone and extended out only a few thousand miles, and because the Moon orbits Earth at an angle to the equator Apollo 11 was able to avoid the most intense part of this belt. Also, as with any object that is thrown upwards in Earth’s gravity, as soon as the S-IVB shut down its engine it began to slow as it pursued a ballistic trajectory. At that time it was at an altitude of 177 nautical miles and was climbing at 21,345 nautical miles per hour. When Collins separated the CSM from the S-IVB, their altitude was over 3,000 nautical miles, and this distance had doubled by the time he completed the transposition and docking 10 minutes later. The radiation received was therefore no worse than that involved in having a chest X-ray. The radiation within the Earth’s magnetic field originates from the ‘solar wind’, which is a flow of charged particles emanating from the Sun. This was discovered in 1962 by Mariner 2, the first spacecraft to report on conditions beyond the realm dominated by the Earth’s magnetic field. Cislunar space – the environment between Earth and the Moon – is comparatively benign, unless a ‘solar flare’ directs a blast of charged-particle radiation in our direction. In terms of sun spots, the intensity of solar activity varies with an 11-year periodicity and, in fact, 1969 was a risky time to be heading for the Moon!

Looking back at Earth, which was rapidly shrinking, Armstrong displayed his keen sense of geography – a childhood passion. Their departure trajectory offered a better view of the northern hemisphere than of southern latitudes. ‘‘Houston,’’ he called, ‘‘you might be interested that out of my left-hand window right now, I can observe the entire continent of North America, Alaska and over the pole, down to the Yucatan peninsula, Cuba, the northern part of South America – and then I run out of window.’’

Meanwhile, Collins had inserted electrical plugs to feed power through to the LM’s heaters and to pyrotechnics in the adapter. McCandless gave them the go – ahead to retrieve the LM. Precisely one hour after initiating the transposition and docking sequence, and now 12,600 nautical miles from Earth, Collins fired the charges to release the LM, and springs eased the 98,000-pound docked spacecraft away from the spent stage. If the charges had failed, the CSM would have undocked and gone on to fly an Apollo-8-style mission in lunar orbit, but this would have been a poor consolation.

The next task, some 20 minutes later, was to perform a manoeuvre to increase the rate of separation from the spent S-IVB. The cutoff velocity at TLI had been set marginally faster than that of the ideal trajectory, with the intention of using the service propulsion system (SPS) of the CSM to cancel the excess. This engine had been designed in such a manner that it was unlikely not to fire, but it was wise to test it early on. Delivering 20,500 pounds of thrust, it would be able to impart the desired velocity change (delta-V) of 19.7 feet per second in 3 seconds, which was just long enough for the telemetry to verify the propellant supply, the combustion chamber pressure and the stability of the gimbal. There was no need for an igniter because the hydrazine-based fuel and nitrogen tetroxide, being hypergolic, ignited immediately on coming into contact after being fed through a pattern of holes in the injector into the combustion chamber.

After running through the post-burn checklist, Armstrong returned to the view of Earth. “We didn’t have much time to talk about the view out the window when we were preparing for LM ejection, but up to that time we had the entire northern part of the day hemisphere visible – including North America, the North Atlantic, and Europe and the northern region of Africa. There was a cyclonic depression over northern Canada, east of Athabasca. Greenland was clear, and it appeared that we were seeing just the icecap. All of the North Atlantic was pretty good. And Europe and northern Africa seemed to be clear. Most of the United States was clear. There was a low, it looked like a front, stretching from the centre of the country, up north of the Great Lakes and on into Newfoundland.’’

“I didn’t know what I was looking at,’’ added Collins, “but I sure did like it!’’

“The view must be pretty good from up there,’’ McCandless agreed. “We show you about 19,000 nautical miles out now.’’ Although this was the altitude at which satellites in geostationary orbits reside, Apollo 11 was far above the plane in which such satellites operate.

If the S-IVB were to pursue the trajectory established by TLI, then it, like the spacecraft, would pass just in front of the leading limb of the Moon. To eliminate any possibility of a collision in transit, once Apollo 11 was clear of it, the ground commanded the S-IVB to execute a venting process designed to deflect its path to pass close by the trailing limb for a gravitational ‘sling shot’ into solar orbit. This venting would involve several phases over the period of about 40 minutes, and the planners had worked out how the spacecraft should be oriented to enable the crew to observe it.

‘‘We’ve completed our manoeuvre to observe-the-slingshot attitude,’’ Collins reported, ‘‘but we don’t see anything – no Earth, and no S-IVB.’’ Houston provided a revised attitude, and Collins started the manoeuvre, but because he had not only used more propellant than expected during the transposition and docking, but had also undertaken a fruitless manoeuvre, he initiated this new manoeuvre at a slow rate.

The venting could not be postponed because, once commanded, the Instrument Unit could not be interrupted. ‘‘It doesn’t look to us like you will be able to make it around to the observation attitude in time,’’ McCandless warned. ‘‘We recommend that you save the fuel.’’

‘‘Our manoeuvre has already begun,’’ pointed out Collins, ‘‘so it’s going to cost us about the same amount of fuel to stop it no matter where we stop it, and we may as well keep going.’’

‘‘We’ve got the S-IVB in sight at what I would estimate to be a couple of miles away,’’ announced Aldrin several minutes later. ‘‘The dump appears to be coming out at radially opposite directions.’’ As this preliminary part of the sequence was to be non-propulsive, the stage was venting oxidiser from opposite sides at the rear. About 25 minutes later, the venting was switched to occur through the J-2 engine, but by then the S-IVB was no longer visible. Finally, the two auxiliary propulsion system modules on the rear of the stage were fired to complete the manoeuvre.

As McCandless read up instructions to reconfigure the fuel cells that generated electrical power, the astronauts started their first meal. ‘‘If we’re late in answering you,’’ Collins apologised, ‘‘it’s because we’re munching sandwiches.’’

‘‘I wish I could do the same here,’’ said McCandless.

‘‘No. Don’t leave the console!’’ Collins warned. ‘‘Flight doesn’t like it. How is he today?’’ The flight director was Clifford Charlesworth, and Collins had served as his CapCom during the Apollo 8 mission.

‘‘Oh, he’s doing quite well,’’ McCandless laughed.

‘‘I think today is the birthday of California,’’ Armstrong called. ‘‘I believe they are 200 years old, and we send them a happy birthday. I think it is also Dr George Mueller’s birthday, but I don’t think he’s that old!’’ George E. Mueller, Director of the Office of Manned Space Flight, was celebrating his 51st birthday.

Six hours into the mission, Charlesworth’s Green Team handed over to Gene Kranz’s White Team, and Charlie Duke took over as CapCom. After crossing the road to brief the press in the News Center, Charlesworth joined his controllers in the ‘Singing Wheel’, a red-painted wooden barn of a building that housed the bar that served as a ‘watering hole’ for off-shift flight controllers heading home.

Having taken sextant sightings to realign the inertial platform, Collins initiated a deep-space navigation test. This P23 exercise required him to measure the angles of five stars relative to Earth’s horizon. In each case, the computer was to orient the vehicle to enable the sextant to measure from the ‘substellar point’. However, the system was not aligning properly, and a measurement along a line that was not perpendicular to the horizon would yield an inaccurate result. The technique was valid, it was simply that something had gone amiss in planning. But he persevered because the data would help the engineers to determine the problem. The test was scheduled at this time in order to confirm the ability to make such measurements before the spacecraft was so far away that Houston could not provide a check. This technique was intended primarily for navigating the approach to re-entry, in order to provide a contingency against loss of communications on the way home.

Meanwhile, first Aldrin and then Armstrong doffed their pressure suits. It was a dynamic process involving a colleague unzipping the rear of one man’s suit and holding him stable while he squeezed out. After finishing his navigation exercise, Collins joined them. With the various parts of the three suits adrift, there was, as Aldrin later put it, ‘‘a great deal of confusion, with parts and pieces floating about the cabin as we tried to keep the logistics under control’’. The suits were carefully folded, stuffed into storage bags and stowed beneath a couch. It was a great relief to remove the urine-collection and fecal-containment devices, which were stowed in a locker in the lower equipment bay. There was no toilet. Urination would be through a tube into a plastic bag that would be periodically vented overboard into vacuum. Defecation would involve the use of a plastic bag, part of which fitted over the hand like a glove. When finished, a germicide pill would be inserted into the bag to prevent bacteria generating gas. This ‘glove bag’ had proved effective on Gemini flights, when, because of the pill, it was euphemistically referred to as a ‘blue bag’. Used bags were stowed in a special container in the lower equipment bay. It typically took 45 minutes to defecate. The use of the bags did not obviate the associated odours, however.[20] Over their constant-wear garments the men wore two-piece teflon-fabric flight suits. With the crew in ‘shirt sleeves’ and the centre couch removed, the cabin appeared considerably larger. The decor was ‘battleship grey’. At an early stage a psychologist had recommended that, in order not to cause disorientation, there ought to be a two-colour scheme with brown below a certain horizontal level and blue above it, which sounded very reasonable until it was pointed out that in weightlessness there was no unique sense of ‘up’, and, by the psychologist’s own logic, if the colour scheme really did matter, then an inappropriate one would be upsetting! Aldrin, who had mastered weightlessness spacewalking on Gemini 12, found the freedom of movement in the command module enjoyable because, as he put it, he was spacewalking indoors! Fortunately, due to the care taken during their first few hours in space, none of the Apollo 11 crew developed any symptoms of ‘space sickness’.

The checklist for donning and checking the accoutrements required to venture out onto the surface was lengthy and excruciatingly detailed. First, each man unstowed his PLSS from its mount on the side wall and stood it on the floor by the forward hatch, then the bags containing the extravehicular gloves and helmet augmentation were retrieved and deposited on the floor next to the backpacks. Next, Armstrong retrieved the OPS packages from the stowage compartment on the side wall. In the event of the primary oxygen supply failing during the moonwalk, the OPS – which would be mounted on top of the PLSS backpack – contained sufficient oxygen to facilitate an emergency ingress and switch back to the cabin’s supply. Finally, he retrieved the remote control units containing status displays for the PLSS and radio system that were to be worn on the chest, and the light-blue deeply treaded rubber overshoes for firm traction outside in the weak lunar gravity. After Aldrin assisted Armstrong to put on his overshoes, Armstrong did so for Aldrin. Aldrin transferred his PLSS to the circular cover of the main engine of the ascent stage, added the OPS, then turned around and reversed up against the backpack. Armstrong helped him to fasten the waist and shoulder harnesses, which clipped to rings on the suit, attach the chest unit to the shoulder harnesses, and run the oxygen umbilicals from the PLSS to the sockets on the front of the suit. Aldrin then helped Armstrong to do likewise. The next step was to conduct a communications check with the portable radios. Aldrin disconnected his cabin communications umbilical and plugged in the one from his PLSS, and Armstrong did the same. As the backpacks projected 10 inches to the rear, they greatly reduced the scope for movement in the cramped cabin. On Earth the backpack weighed 120 pounds but on the Moon it was only 20 pounds. However, it retained its inertia and if it were to even nudge against the lightweight structures it would deliver a significant impact.

“Houston,” Collins called, “could you enable the S-Band relay at least one way from Eagle to Columbia, so that I can hear what’s going on?”

“There’s not much going on at the present time,’’ McCandless noted, “but I’ll see what I can do about the relay.’’

As part of the PLSS communications checks, the crew switched to VOX, and although this enabled people to listen in, the terse to and fro was not particularly illuminating for anyone without a checklist. McCandless participated only when addressed.

As 108 hours approached, Public Affairs Officer Jack Riley announced, “We do not at this time have a good estimate for the start of the EVA.’’ The astronauts were 30 minutes behind on the checklist, and slipping further. Jan Armstrong, on the floor in front of the television, laughed. “It’s taking them so long because Neil is trying to decide about the first words he’s going to say when he steps out on the Moon.’’ In the Collins home there was impatience rather than tension. Pat Collins sat with a plate of lasagne in the company of Clare Schweickart, Barbara Gordon and Mary Engle. Rusty Schweickart was attempting to follow the preparations by listening to the squawk box, but the astronauts’ commentary was not particularly informative. Noting that her husband had requested a one-way relay to enable him to listen in to transmissions between Eagle and Houston while on the near side of the Moon, Pat suspected that he would be on the far side when the moonwalk started, and therefore miss it. Joan Aldrin was relaxing, listening to Duke Ellington records. On breaking off, she said to Audrey Moon, “I’ve thought sometimes, privately, and may even have said so to Buzz, that he was so caught up in the mechanics of all this that he really hadn’t realised the significance of what he was doing; but now I really think he did!’’ She settled down to a plate of buffet nibbles and awaited developments.

Advancing through the preparations, Aldrin inserted the circuit breaker for the television system. “Houston, are you getting a signal on the television?’’ he asked. The MESA compartment was still in its stowed position, denying illumination to the camera inside, but the system was transmitting.

“The data we’re receiving looks good,’’ said McCandless, “and we’re getting synchronisation pulses and a black picture.’’

With the Sun low in the east, the 23-foot-tall vehicle was casting a very long shadow, and the ladder on the forward leg was facing westward. “You’ll find the area around the ladder is in a complete dark shadow,’’ Armstrong pointed out, “so we’re going to have a problem with the television, but I’m sure you’ll be able to see the lighted horizon.’’

“We request that you open the television circuit breaker,’’ McCandless called. “It’s been on about 15 minutes now, with the MESA closed.’’ Houston wanted it switched off to preclude the camera overheating in the insulated compartment. Aldrin was to have pulled the circuit breaker immediately following the test, but had missed a step on the checklist.

“Do we have a Go for cabin depress?’’ Armstrong asked.

When there was no response, Aldrin quipped about VOX letting Houston listen

in, “They hear everything but that!” He made the call himself just in case there had been a fault with Armstrong’s radio. “Houston, this is Tranquility. We’re standing by for a Go for cabin depress.’’ Actually, the delay was because Charlesworth was polling his flight controllers. McCandless ought to have replied to Armstrong with a ‘Standby’.

“You’re Go for cabin depressurisation,’’ McCandless replied finally.

In fact, they were currently some 22 minutes behind their 108:00 estimate, and had just received permission to proceed with the final phase of the preparations; it would be another half hour before they would be ready to start the depressurisation of the cabin. With the moonwalk imminent, the Apollo 12 LM prime and backup crews of Pete Conrad, Al Bean, Dave Scott and Jim Irwin joined McCandless. Gene Kranz returned and sat with Charlesworth to watch the telecast on one of the wall screens.

Having configured the cabin for exposure to vacuum, Armstrong and Aldrin were able to finish suiting. Once the cooling system had been checked, the water umbilical was run from the PLSS to the suit to circulate water through the liquid coolant garment. The umbilical to the cabin’s oxygen system was removed, and the OPS umbilical was plugged into the vacant sockets. After he had applied an anti-fogging agent to the inside of Aldrin’s ‘bubble’ helmet, Armstrong slipped it over Aldrin’s head and locked it into position. He followed up with the polycarbonate shell incorporating the visor assembly that provided an inner and outer visor. The outer visor had a gold coating to reflect the harsh glare from the Sun which, in the absence of an atmosphere, was not only bright but also full-spectrum. Aldrin then repeated the procedure for Armstrong. Finally, they donned their extravehicular gloves, which had coverings of woven steel-fibre and rubberised finger tips for a modicum of dexterity. Taken together with the PLSS, OPS, helmet augmentation, extravehicular gloves and overshoes, the suit was described in NASA-ese as the extravehicular mobility unit. Aldrin wore a watch over the gauntlet-like sleeve of the right glove, but Armstrong decided to leave his watch inside as an emergency backup to the spacecraft’s event timer. A checklist for the external activities had been stitched onto the gauntlet of each left glove, listing that man’s specific tasks. Owing to uncertainty regarding the metabolic rate of an astronaut working on the lunar surface, and the fact that no one knew for certain how long the coolant water would last, the duration of the moonwalk had been set conservatively. However, the ‘clock’ on the life – support system started when the PLSSes were activated to pressurise the suits prior to depressurising the cabin.

‘‘Now comes the gymnastics,’’ Armstrong observed.

Aldrin carefully reached down and opened the valve built into the waist-high forward hatch, and then they monitored the pressure meter, which was initially at 4.8 psi. The depressurisation was slowed by the bacterial filter incorporated into the valve to protect the lunar environment from terrestrial biota, lest this be sampled, returned to Earth and misinterpreted as evidence of lunar life. As the pressure decreased, the rate of decrease slowed as it took time for the remaining gas molecules to find their way to the vent valve. ‘‘It sure takes a long time to get all the way down, doesn’t it?’’ mused Aldrin. When the pressure fell below 0.2 psi he tried the hatch, but it would not budge.

‘‘Neil, this is Houston. What’s your status on hatch opening?’’ McCandless called 10 minutes into the procedure.

‘‘Everything is Go here. We’re just waiting for the cabin to blow enough pressure to open the hatch. It’s about one-tenth on our gauge now,’’ Armstrong replied. Fifteen seconds later, he announced, ‘‘We’re going to try it.’’ But even at 0.1 psi, the 32-inch-square hatch would not open. Aldrin suggested that they also open the overhead valve, but they decided to wait. The cabin had vented sooner in altitude chamber tests, but as a chamber never establishes a perfect vacuum this had not given an accurate time measurement. As the hatch was only a thin metal cover of little rigidity, Aldrin carefully peeled back one of its corners to break its seal. Ice crystals formed as the residual air rushed out. Aldrin then readily hinged the hatch in towards his feet. “The hatch is coming open,” Armstrong announced.

“The valve’s in Auto,” Aldrin confirmed as he set the hatch valve to enable it to be operated from the outside.

The final task was to install the lunar equipment conveyor (LEC). This was a long nylon tether with a hook at each end to enable it to be linked into a loop and run around a pulley on a fixture located in the cabin. It had additional hooks on it to attach equipment for transfer to or from the surface. For Armstrong’s egress, the tether was hooked to the tie-down strap of his neck-ring as a safety precaution. With the hatch open wide, Armstrong faced aft and, with one hand leaning on the cover of the ascent engine, carefully lowered himself until he was kneeling on the floor with his feet in the hatch. Then Aldrin provided cues to help him to reverse out. With the bulky PLSS on his back it was a tight fit, but the hatch was already as large as the vehicle’s design could accommodate. Rusty Schweickart called to those in the Collins home that the hatch was finally open. Listening to Aldrin assisting Armstrong out, Schweickart remarked, “Don’t bump into anything! Just find the ladder, Neil!’’ When CBS anchorman Walter Cronkite wondered why Armstrong was taking so long, Schweickart muttered that it was “because he doesn’t have eyes in his rear end’’. Armstrong reversed out across the porch more or less flat on his stomach until his boots were at the far end, then he grasped the side rails and pushed himself up onto his knees. Aldrin pushed a bag of packaging through the hatch, and Armstrong dumped it over the side. By this point, they had been living off their PLSS resources for 25 minutes.

“Houston, I’m on the porch,’’ Armstrong announced.

Fifteen seconds later, Aldrin started the Maurer 16-millimetre camera that he had earlier installed on the bracket in the top-right corner of his window. Since he had no viewfinder, he adjusted it as best he could to view Eagle’s shadow, with a little of the illuminated lunar surface to each side. Armstrong entered the frame 30 seconds into the sequence.

“Stay where you are a minute, Neil,’’ called Aldrin. In preparation for his own egress, Aldrin partially closed the hatch to enable him to cross to the left-hand side of the cabin, and he did not want Armstrong to snag the tether on the hatch.

“Can you pull the door open a little more?’’ Armstrong prompted, when told he could continue.

“All right,’’ said Aldrin, and he opened the hatch fully, into the space where he had previously been standing.

As Armstrong prepared to descend the ladder, Columbia passed ‘over the hill’ and, deprived of his relay, Collins’s eagerness to hear what Armstrong would say as he stepped onto the lunar surface was frustrated.

In case Armstrong had forgotten to deploy the MESA, Aldrin asked, ‘‘Did you get the MESA out?’’

“I’m going to pull it now,” Armstrong replied. He located the D-ring alongside the porch using his left hand, and tugged it. The pallet on the front-right quadrant of the descent stage hinged down until just short of horizontal. “Houston, the MESA came down all right.’’

“Roger,” replied McCandless. “And we’re standing by for your TV.’’

“The television circuit breaker is in,’’ reported Aldrin. The transmission was by the high-gain antenna.

The objective of the Lunar Orbiter series was to reconnoitre possible landing sites for Apollo. As they had insufficient film to search for sites, they concentrated on sites that appeared suitable on the basis of telescopic observations. The Apollo Site Selection Board reduced an initial list of 30 candidates – all located on the near side of the Moon within 45 degrees of the meridian and 5 degrees of the equator – to a short-list of five by applying the following operational factors:

Of which more in chapter 10.

The primary objective of the Surveyor missions was to investigate the dark plains. Five Apollo Landing Sites (ALS) were selected in the equatorial zone for the early Apollo landings (bottom).

• Smoothness: Relatively few craters and boulders.

• Approach: No large hills, high cliffs, or deep craters that could result in incorrect altitude signals to the lunar module landing radar.

• Propellant requirements: Least potential expenditure of spacecraft propellants.

• Recycling: Effective launch preparation recycling if the countdown were to be delayed.

• Free return: Sites within reach of the spacecraft launched on a free-return translunar trajectory.

• Slope: Less than 2-degree slope in the approach path and landing area.

The flight dynamics team insisted that the primary site be located in the eastern hemisphere, in order to allow room further west for one or two suitably lit backup sites in the event of the launch being postponed by several days. As the launch ‘windows’ for a given site occurred only once per month, it was thought better to go for a secondary site several days late than to wait a month for the primary site to present itself again. The time of landing had to be just after local sunrise, as the Sun was required to be low on the horizon to cast sufficient shadows to reveal surface topography. Because the Sun traverses the lunar sky at a rate of 12 degrees per 24 hours, the backup sites were set 12, 24 or 36 degrees apart in lunar longitude to ensure that the illumination would be right for a delayed mission. On the other hand, the primary site could not be too far east, as this would not allow sufficient time after the final limb crossing to perform the navigational checks prior to initiating the powered descent. All sites had to be within 5 degrees of the lunar equator because a higher latitude would require a less propellant-efficient trajectory, and propellant economy was a priority for the first landing mission. Furthermore, the approaches to the sites had to be flat in order not to complicate the task of the landing radar. These operating constraints restricted the first landing to an eastern dark plain near the equator, which put the primary landing site in either the Sea of Tranquility or the Sea of Fertility, the backup site in the Meridian Bay, and the reserves in the Ocean of Storms. However, the Sea of Fertility was too far east to accommodate the final navigational update, which left the Sea of Tranquility, where there were two sites. The trajectory of Apollo 8 had been timed to inspect the easternmost site, ALS-1, called 2P-2 by the Lunar Orbiter team, at ideal illumination.

The time of the landing was determined by the location and the acceptable range of Sun elevation angles. The range of these angles ran from 6 to 14 degrees, east to west. Under these conditions, the visible shadows of craters would aid the crew in recognising topographical features. As the Sun angle approached the descent angle, the mean value of which was 16 degrees, the viewing conditions would be degraded by a ‘washout’ phenomenon in which backward reflectance was high enough to eliminate contrast. Sun angles above the flight path were not as desirable, because shadows would not be readily visible unless the Sun was significantly outside the descent plane. Because lunar sunlight incidence changed about 0.5 degree per hour, the Sun elevation angle restriction defined a 16-hour period, recurring every 29.5 days, when landing at a given site could be attempted. The number of Earth-launch opportunities for a given lunar month was equal to the number of candidate landing sites. The time of launch was primarily determined by the allowable variation in launch pad azimuth. A total launch pad azimuth variation of 34 degrees afforded a launch period of 4 hours 30 minutes. Two launch windows occurred each day. One was available for a translunar injection over the Pacific Ocean, and the other over the Atlantic Ocean. The injection opportunity over the Pacific Ocean was preferred because it usually permitted a daytime launch.

The REFSMMAT for the translunar coast used the ecliptic, which is the plane in which Earth orbits the Sun: two of the three axes of the REFSMMAT were relative to the ecliptic, and the third was aligned along the Earth-Moon line at the time of TLI. To prevent one side of the spacecraft roasting and the opposite side freezing in the constant sunlight of cislunar space, it was to be oriented with its principal axis perpendicular to the ecliptic, then set rolling on a 20-minute cycle for passive thermal control (PTC) in a regime more popularly known as the barbecue mode. This had to be established before the astronauts could retire for the night. There were four options in the flight plan for midcourse corrections to refine the trajectory for lunar orbit insertion. The first was scheduled 9 hours after TLI, but since the delta-V was only 17 feet per second the burn was deleted, and the initiation of PTC advanced. Ten hours into the mission, after orienting the spacecraft perpendicular to the ecliptic, Collins gave the computer 20 minutes in which to fire the RCS thrusters as necessary to eliminate any axial wobble.

While waiting, Aldrin enquired about their altitude, which was 50,000 nautical miles. “It’s a beautiful sight,” he enthused, referring to Earth. “I can see snow on the mountains of California. It looks like LA doesn’t have much of a smog problem today. With the monocular, I can discern a definite green cast to the San Fernando Valley.’’

“How’s Baja California look, Buzz?’’ Duke asked.

“It has got some clouds up and down it, and there is a pretty good circulation system a couple of hundred miles off the west coast of California.’’

“Your rates look really great, now,’’ Duke called a few minutes later. “You can start your PTC.’’

“If you would like to delay PTC for 10 minutes or so, we can shoot you some television of a seven-eighths-phase Earth,’’ Armstrong offered.

Duke checked whether Goldstone was configured to receive television; it was. “It will be recorded at Goldstone and then replayed over here, Neil. Any time you want to turn her on, we’re ready.’’

“We’re sending a picture of Earth right now. Let us know if they’re receiving at Goldstone.’’

“Goldstone says it looks great,’’ Duke confirmed.

Armstrong was pointing the camera through the window beside his couch, and they had put up shades to prevent the Sun entering the other windows and causing internal reflections. He zoomed in until Earth filled the screen, and was pleased to observe that the automatic gain control adjusted the aperture to compensate.

“We’d like 10 minutes’ worth of television,’’ Duke requested. “And we’d like a narrative on the exterior shots. We also suggest you might try an interior position.’’

“We’re seeing the eastern Pacific Ocean,’’ replied Armstrong. “We’ve not been able to visually pick up the Hawaiian Island chain, but we can clearly see the western coast of North America – the United States, the San Joaquin Valley, the High Sierras, Baja California, and Mexico down as far as Acapulco and the Yucatan peninsula. And you can see on through Central America to the northern coast of

South America, Venezuela and Colombia. I’m not sure you’ll be able to see all that on your screen down there.’’

“Roger, Neil,’’ acknowledged Duke. “We wanted a narrative so that when we get the playback we can correlate what we’re seeing.’’

Although Armstrong and Aldrin had each remarked on the diminishing view of Earth, Collins had been too busy sighting on stars and operating the computer. “I haven’t seen anything but the DSKY so far,’’ he pointed out.

“It looks like they’re hogging the windows,’’ Duke consoled.

“You’re right,’’ Collins confirmed.

There was a distinct sense of distance – Earth and the Moon were both far off – but the distances were so immense that, in the absence of points of reference along the way, there was no sensation of movement despite the spacecraft’s high speed.

After 15 minutes, Duke announced, “You can terminate the television at your convenience, and then initiate PTC.’’ The impromptu telecast had verified that the television system was working beautifully.

Collins initiated the roll. With the Sun, Earth and Moon passing in procession by the windows, the illumination in the cabin became very dynamic.

As the camera was packed away, Armstrong gave a crew status report, reading their individual radiation monitors, noting that they had not taken any medications, and saying that in his opinion they were “fit as a fiddle’’, by which he meant they had not developed any symptoms of ‘space sickness’.

“As far as we can see,’’ Duke agreed, ‘‘you’re cleared for some zzzz’s.’’ In fact, as a result of having deleted midcourse correction 1, they were two hours ahead on the time line.

When testing the CSM with Apollo 7, Wally Schirra’s crew had maintained a staggered sleeping cycle in which there was always one man awake to monitor the spacecraft. On Apollo 8 Frank Borman’s crew had done the same, with the result that they slept poorly and were exhausted on entering lunar orbit. It was therefore decided that future crews should adopt a single sleep cycle. Armstrong was eager for his crew to conserve their energies in transit, to ensure that they would be alert on arrival in lunar orbit. In fact, it had been agreed that he and Aldrin would act as passengers because their mission would not start until they were in lunar orbit, and Collins would act as the chauffeur for the translunar coast. Although Duke signed off early, the crew did not retire until 10.30 pm on their Houston-time watches. Having arisen very early to prepare for launch, it had been a long day, and in their last few hours they were feeling distinctly drowsy. They had their supper, placed shades over the windows to block out the Sun and dimmed the internal lamps. Armstrong and Aldrin then disconnected their communications links and snuggled into enclosed hammocks – in effect mesh sleeping bags slung beneath the side couches – while Collins, the ‘watch keeper’, donned a lightweight headset with its earpiece on low volume, in case of a call from Mission Control, and strapped into the left-hand couch using a lap belt; as he rested, he realised that he no longer had any discomfort in his knee.

Cliff Charlesworth, Gene Kranz and Glynn Lunney were to rotate 8-hour shifts during the translunar coast. The ‘graveyard’ shift was handled by Lunney’s Black

Team. For the first 24 hours of a mission, flight controllers maintain a particularly close eye on the telemetry in order to identify the quirks of the new craft early on, and to establish norms and consumable rates.

Goldstone sent the taped telecast to Houston by a land line, where the signal was fed through conversion equipment for display on the wall screen and release to the media. On arriving home from the Cape and finding the press on her lawn, Jan Armstrong informed them that it had been a long day and she really needed to sleep, but happened to switch on her television as the networks started to run the telecast; the other wives missed it.

On the flight plan, the moonwalk was scheduled to be made when the 210-foot – diameter dishes at Goldstone and the Parkes Observatory in New South Wales, Australia, would both have a clear line of sight in order to provide 100 per cent redundancy in these large antennas. However, advancing the schedule meant that the Parkes antenna, which could not dip all the way down to the horizon, could not receive until the Moon was well up; and in any case, wind gusts threatened to cut operations short. And since a problem at Goldstone was degrading the slow-scan television signal, the smaller 85-foot antenna at the Honeysuckle Creek Tracking Station 25 miles from Canberra, Australia, became the prime receiver for coverage of the egress. Built in 1967, Honeysuckle Creek had tracked previous missions but as Bernie Scrivener, the administrative officer, noted, “Somehow this seemed to be much more important; this was the day for which everyone on the station had worked and trained.’’ Australia’s Prime Minister, John Gorton, joined a large group of technicians to witness the event. At 11.15 am local time, the Moon rose and the signal was strong. The Westinghouse black-and-white camera provided 320 lines of resolution at a scan rate of 10 frames per second. As television technician Ed von Renouard reflected, “When I was sitting there in front of the scan converter waiting for a pattern on the input monitor, I was hardly aware of the rest of the world. I heard Buzz Aldrin say ‘Television circuit breaker in’.’’ The signal came in. “When the image first appeared, it was an indecipherable puzzle of stark blocks of black at the bottom and grey at the top, and was bisected by a bright diagonal streak. I realised that the sky should be at the top – and on the Moon the sky is black.’’ Several weeks earlier, NASA had noticed that when the MESA was opened the camera affixed to it would be oriented upside down, and a switch had been installed at each ground station to flip the picture, and when von Renouard threw the switch ‘‘all of a sudden it made sense’’.

As one of the 10-foot-by-10-foot Eidophor screens in Mission Control flickered to life, it prompted cheers in the viewing gallery. ‘‘We’re getting a picture on the TV,’’ McCandless announced.

‘‘You got a good picture, huh?’’ Aldrin asked.

‘‘There’s a great deal of contrast in it,’’ McCandless replied, ‘‘and currently it’s upside down on our monitor, but we can make out a fair amount of detail.’’ In fact, the initial feed to Houston was by a land line from Goldstone, where the technician waited 30 seconds before flipping the image upright. Unfortunately, the problem with the conversion system made the image extremely contrasty.

“Will you verify the aperture I ought to have on the camera?” Aldrin asked. He was referring to the Maurer.

“Stand by,” McCandless re­plied.

Since the MESA rotation had stopped short of 90 degrees, the television view depicted the hor­izon tilted slightly down to the right. Watched by a mesmerised audience, Armstrong carefully descended the nine-rung ladder.

“Neil, we can see you coming down the ladder now,” reported McCandless.

The specifications for the extravehicular suit had required it to protect against temperatures in the range -250°F to +310°F, the former representing deep shadow and the latter full sunlight plus heat radiated by the surface. Although the ladder was in shadow, Armstrong was able to hold onto it without ill effects. Indeed, as he would later recall, “At no time could I detect any temperature penetrating the insulated gloves as I touched things.” hacking an atmosphere, the lunar surface is exposed to micrometeoroid bombardment. The tough outer covering was judged sufficient to protect against microscopic motes impacting at cosmic speeds.

On touchdown, the narrow lower section of the strut was to act as a piston and slide into the wider main strut and, by virtue of crushing a honeycombed filler, absorb the shock of the vehicle falling the final few feet, but Eagle had landed so gently that there was no significant compression and the interval from the lowest rung on the ladder to the foot pad was at almost its maximum 3.5 feet – a fact that Armstrong discovered when he jumped backwards off the final rung and, sliding his hands down the rails to maintain his stability, landed with both feet within the 3- foot-diameter pad. He jumped back up onto the ladder to verify that ascent was feasible, then down again. Meanwhile, Aldrin opened the f-stop of the Maurer on his own initiative. Although this washed out the ground beyond the shadow, it much improved the view of Armstrong. Twenty seconds later, McCandless issued the recommended settings, “Buzz, f/2 and 1/160th second for shadow photography on the sequence camera.”

At this point the Network controller in the Mission Operations Control Room noticed that the video from Honeysuckle Creek, which was being transmitted by microwave to Sydney and then relayed by an Intelsat geostationary satellite over the Pacific Ocean, was clearer, and so he switched to this. Although NASA fed the Honeysuckle picture to the commercial television networks, it used Goldstone’s audio.

The first step

For Armstrong, being a test pilot, the significant achievement of the mission had been the act of landing on the Moon. But for the public, that was only the prelude to a man making an imprint of his boot on the lunar surface.

“I’m at the foot of the ladder,” Armstrong announced. Standing on the foot pad, holding the ladder with his right hand and bent forward slightly in order to balance his PLSS, he inspected the surface to the left of the pad, as he had done in training. Although he was deep in Eagle’s shadow, sunlight backscattered from the zero-phase angle illuminated the shadowed side of the vehicle, enabling him to see reasonably well. “The LM foot pads are only depressed in the surface about 1 or 2 inches, although the surface appears to be very, very fine grained; as you get close to it, it’s almost like a powder.’’ At home, his wife urged him to “be descriptive”. Joan Aldrin clapped her hands in delight, “I can’t believe this’’. In the Collins home, someone remarked in amazement, “This is science fiction!’’ Although the picture from the slow-scan camera was ‘ghostly’, it was remarkable (and, oddly, not envisaged by science fiction) that people on Earth were able to watch their representative take his first step onto the lunar surface ‘live’ on television. The Mission Operations Control Room was totally silent. In the News Center, journalists were watching on a theatre­sized Eidophor screen. Ironically, the town of Carnarvon, which hosted one of the tracking stations of the Manned Space Flight Network, had no television facilities. However, the Australian Broadcasting Corporation had arranged for the Overseas Telecommunications Commission to relay the moonwalk via satellite. In the local theatre the townspeople had installed a 14.5-inch set which people at the rear of the hall watched through binoculars!

Having described the strut and the adjacent surface, Armstrong announced, ‘‘I’m going to step off the LM now.’’ On the translunar coast, Aldrin had asked him if he had decided what he would say on stepping onto the surface, and he had said he was still thinking it over. Having rejected quotations from Shakespeare and the Bible, and things that he deemed to be pretentious, it dawned on him as he stood at the foot of the ladder that there was, in fact, only one thing to say! Holding onto the ladder with his right hand, he placed his left boot firmly on the surface alongside the pad. ‘‘That’s one small step for a man, one giant leap for Mankind.’’[33] [34]d The historic first words having been issued, the Mission Operations Control Room broke into hearty applause. Dave Scott, who flew on Gemini 8 with Armstrong, would later reflect that it was typical of the man to have deliberated for so long over what to say, and then expressed so much in so few words.

Armstrong released his grip on the handrail of the ladder and stepped fully off the foot pad. Walter Cronkite proudly told his CBS audience that a 38-year-old

American was now standing on the surface of the Moon. When Armstrong scraped his foot across the surface, he noticed that the dark powdery material coated his overshoe. “The surface is fine and powdery. I can kick it up loosely with my toe. It adheres in fine layers like powdered charcoal to the sole and sides of my boots.” Although his boots only slightly impressed the surface, the material preserved the imprint of his boots very well. “I only go in a small fraction of an inch – maybe one – eighth of an inch – but I can see the prints of my boots and the treads in the fine, sandy particles.”

Wearing the 180-pound extravehicular mobility unit, Armstrong’s mass was 340 pounds, but in the weak lunar gravity he weighed only one-sixth of this and was light on his feet. He did not feel the weight of the suit, since its internal pressure made it self-supporting. Holding the ladder with both hands, he did several knee-bends and then took a few steps away from the foot pad, briefly leaving the view of the television camera. Some members of the medical community had expressed concern that the astronauts would have difficulty in rapidly adapting to lunar gravity, and had urged that time be reserved for acclimatisation, with an immediate recall if this were to prove difficult. However, this ignored the fact that they would have been exposed to lunar gravity inside the LM for several hours prior to egressing, during which time they would be acclimatising – if, indeed, a period of acclimatisation should prove necessary. Others had expressed concern that if an astronaut were to fall onto his back he might have difficulty regaining an upright stance. If Armstrong had slipped early on, this may have prompted his immediate recall. He was determined to allay such concern. “There seems to be no difficulty in moving around as we suspected,’’ he continued. “It’s even perhaps easier than the simulations at one-sixth gravity. It is actually no trouble to walk around.’’

Having moved back in order to see beneath the vehicle, Armstrong said, “The descent engine didn’t leave a crater of any size. It has about 1 foot clearance off 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.’’ At this point, he unhooked the LEC from his suit, but kept hold of it. “Buzz, are we ready to bring down the camera?’’

“I’m ready,’’ replied Aldrin. “You’ll have to pay out all the LEC. It looks like it’s coming out nice and evenly.’’

After training had suggested that it would be difficult to carry the loaded rock boxes up the ladder at the end of the moonwalk, the LEC, dubbed the ‘Brooklyn clothes line’, had been devised. It had then been decided to use this to transfer out the Hasselblad camera. Armstrong was to use the LEC in hand-over-hand fashion to lower the equipment transfer bag. Now that he had stepped away from the LM, the illuminated terrain ruined his dark adaptation. ‘‘It’s quite dark here in the shadow, and a little hard for me to verify that I have good footing,’’ he pointed out. ‘‘I’ll work my way over towards the sunlight here, without looking directly into the Sun.’’ He did not want to enter full sunlight because he did not yet desire to lower his gold-coated visor. As he moved off to the southern edge of the shadow, Aldrin elevated the Maurer, and the western horizon appeared in the field of view. At this point, the movie camera exhausted the 8 minutes of film that had remained in the magazine with which Aldrin had set it running. At this point, too, having briefly switched the television feed back to Goldstone, then to Honeysuckle Creek and once again to Goldstone, Houston was informed that the 210-foot antenna at Parkes had finally acquired the signal and, since this had the best image quality to date, it was fed to commercial television networks for the remainder of the moonwalk.

The bodywork of the Hasselblad 500EL Data Camera was highly reflective for thermal control on the lunar surface, and it had an f/5.6 lens with a focal length of 60 millimetres. The shutter speed, aperture and focus were all manual; only the electric film-advance was automatic. The adjustments had been enlarged to enable them to be operated by gloved hands. The astronauts had memorised the exposure settings for different Sun angles. In order to facilitate precise measurements across a frame for ‘data extraction’, a glass plate bearing a grid of 25 crosses had been positioned immediately in front of the focal plane. It was originally intended that the camera would be operated hand-held, but during training Armstrong had suggested that a bracket be added to the chest pack in order to make the camera hands-free. Because the helmet would prevent use of the top-mounted view finder, the rotating mirror and viewing plate had been deleted, and the astronauts had learned to aim by trial and error. They had two cameras, but only one had the modifications for external use.

After removing the Hasselblad from the equipment transfer bag, Armstrong mounted it on his bracket. He draped the LEC beside the forward leg. Noticing that the Maurer had stopped, Aldrin attended to it. In addition to exchanging the film magazine, he moved the camera to a bracket on a bar running horizontally across his window, set the exposure for the illuminated terrain, and pointed it northwest in order to document the locus of most of the external activities. As Armstrong set out to snap pictures for a partial panorama of the site, McCandless prompted him to take the contingency sample. This had priority on the checklist for the early part of the excursion because, if a suit or PLSS problem were to oblige him to retreat before he could fill the rock boxes, or if it should prove impossible to transfer the boxes to the cabin, they might have to return to Earth with only this small sample. Armstrong said that he would collect the sample when he had taken his pictures. He shot nine frames, turning slightly each time to document the horizon running from due south, through west and around to due north. This done, he moved north about 12 feet, stepping out of Eagle’s shadow into sunlight to enable him to see the ground as he took the sample, knowing that this position would be within the field of view of the Maurer. As he still had not lowered his gold-plated visor, he stood with his back to the Sun, drew a scoop from the pocket strapped onto his left thigh, and straightened the multi-segmented handle just as Aldrin restarted the Maurer. As Armstrong scraped the scoop across the surface, he discovered that although the surficial material was loose, it consolidated with depth and prevented the scoop from penetrating more than a few inches. Nevertheless, by dragging the tool across the ground several times he was able to fill the bag.

‘‘It looks beautiful from here, Neil,’’ Aldrin called, referring to the sampling.

Armstrong, presuming Aldrin’s remark to be a comment on the moonscape, replied, “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.’’ Then to Houston he said, “Be advised that a lot of rocks have what appear to be vesicles in their surfaces.[35] Also, I’m looking at one now that appears to have some sort of phenocrysts in it.’’[36] After detaching the transparent sample bag from the scoop he inserted the handle several inches into the ground. On inspecting the contents of the bag, he noted that although the surface generally appeared shades of tan, the sample was black. After sealing the bag, he kneaded it with his fingers, observing that although most of the material was very finely grained there were also fragments of rock. His next task was to put the bag into his thigh pocket, but the peripheral vision through the visor was so limited that he could not see the flap. “Is the pocket open, Buzz?’’

“Yes, it is. It’s not up against your suit though. Hit it back once more. More towards the inside. Okay. That’s good.’’

“Is that in the pocket?’’

“Yes. Push it down. It’s not all the way in. Push it. There you go.’’

“The contingency sample is in the pocket,’’ Armstrong informed Houston, to the relief of the scientists. In fact, they would have preferred the sample taken well away from Eagle because the exhaust plume had disturbed the fine material in the immediate vicinity and potentially contaminated that which remained. In addition, the oxidiser pressure had been relieved soon after landing by venting, and some of the nitrogen tetroxide might have coated the surface. But Armstrong had been told to remain close to the vehicle.

Second man out

After Armstrong had been on the lunar surface for about 15 minutes, Aldrin asked, “Are you ready for me to come out?’’

“Just stand by a second. I’ll move this over the handrail,’’ replied Armstrong. He adjusted the position of the LEC on the strut to ensure that it would not hinder Aldrin’s egress, and then he stood to the southwest in order to document Aldrin’s egress. When Fred Haise alerted Joan to her husband’s imminent appearance, she, as a former actress, observed, “It’s like making an entrance on stage.’’

Before Aldrin left, he gave the Maurer camera a final inspection. On 27 February 1969 Maxime A. Faget, Director of Engineering and Development at the Manned Spacecraft Center, wrote to Owen E. Maynard, chief of the mission operations branch. Knowing that the television coverage of the moonwalk would not be of very high quality, Faget had had high hopes for the film record. But discovering what was intended, he was dismayed. “From the stand point of public information and historical documentation,” he wrote, “I am terribly disappointed to find that although 560 feet of movie film has been set aside for lunar surface use, none will be exposed with the intent of providing a first-class visual appreciation of the astronauts’ activity on the Moon during this singularly historical event. The impression of this occasion will be marred and distorted by the fact that the greatest frame rate [in automatic mode] is 12 frames per second. One can argue that ‘suitable’ (although jerky) motion rendition is produced by double-framing. Nevertheless, it is almost unbelievable that the culmination of a $20 billion program is to be recorded in such a stingy manner.’’ The situation was actually worse than Faget had been led to believe, since with the camera running at its slowest rate of 1 frame per second a 140-foot reel of thin base film was sufficient for only 93 minutes, and because there would be no one available to replace the magazine it would not be possible to document the entire moonwalk.

‘‘All set,’’ called Armstrong. ‘‘You saw what difficulties I was having. I will try to watch your PLSS from here.’’ As Aldrin’s feet appeared in the hatch, Armstrong gave cues to assist him to reverse out along the porch.

Aldrin, ‘‘making sure not to lock it on my way out’’, partially closed the hatch in order to protect the cabin from the harsh thermal environment.

‘‘A pretty good thought,’’ chuckled Armstrong.

‘‘That’s our home for the next couple of hours, and we want to take good care of it,’’ Aldrin added. ‘‘Okay. I’m on the top step.’’ As he started down the ladder he provided commentary because one of his assignments was to evaluate the ability of a man to operate in the lunar environment, ‘‘It’s a very simple matter to hop down from one step to the next.’’ As her husband appeared on the television, Joan screamed with delight, rolled on her back and kicked her legs in the air, then sat up again and blew kisses.

‘‘You’ve got three more steps and then a long one,’’ Armstrong advised.

Aldrin continued his commentary as he prepared to jump down on to the foot pad, ‘‘I’m going to leave that one foot up there, and both hands down to about the fourth rung up.’’

‘‘There you go,’’ said Armstrong as Aldrin jumped.

Following Armstrong’s lead, Aldrin tested jumping back up, but in this case his boot fell short of the lowest rung and dropped down again.

‘‘About another inch,’’ Armstrong noted.

Aldrin jumped up again, this time successfully. It was a matter of recalibrating his muscles for one-sixth gravity. ‘‘That’s a good step,’’ he noted wryly.

‘‘About a 3-footer,’’ said Armstrong.

‘‘Beautiful view!’’ said Aldrin, as he looked left and right while standing on the foot pad.

‘‘Isn’t that something!’’ Armstrong agreed. ‘‘It’s a magnificent sight out here.’’

Impressed by the contrast between the stark shadows and the barrenness of the illuminated surface, Aldrin said, ‘‘Magnificent desolation.’’ Retaining hold of the ladder with both hands, he stepped backwards off the pad, then let go with his left hand and turned to face north. He was struck by the Moon’s small size. To a man

standing on the surface, the horizon was less than 2 miles away, making it very evident that he was on a sphere with the surface falling away in all directions. This had not been so evident when looking out of the window since, being higher, with the horizon further away, he had been able to see to a ‘reasonable’ distance. Standing freely, he noted that it was necessary to lean forward about 10 degrees to balance the mass of his backpack. However, this stance assisted in looking down, and he remarked that although the surface was finely grained and there were some rocks, there were some other objects that looked like clods of dirt. The loose material was different from terrestrial soil which, in addition to fragments of rock, contains the products of chemical weathering and organic humus – the lunar material is best described as a ‘regolith’, this being the term for material composed solely of rock fragments with a seriate distribution of sizes. Since a breccia is a consolidation of rock fragments bound in a matrix of finer material, geologists would subsequently introduce the term ‘regolith breccias’ for the compacted clods of regolith which, although they looked like rocks, readily fell apart when disturbed.

‘‘This pad sure didn’t penetrate far,’’ Aldrin observed.

‘‘No. It didn’t,’’ Armstrong agreed.

As had Armstrong, Aldrin stepped back and peered beneath Eagle, ‘‘There’s absolutely no crater there at all from the engine.’’ Although the plume had blown the dust out radially, it had not excavated the surface. However, there was a mark directly beneath the engine where the probe of the left landing gear had struck the surface.

Armstrong had also observed that whereas the probe on the left leg was bent beneath the vehicle, that on the right leg was bent outward. ‘‘I think that’s a good representation of our sideward velocity at touchdown.’’

As per his checklist, Aldrin continued to familiarise himself, but since he had not set the voice-actuated keying control for his downlink at its maximum setting he was cutting out; at times, much of what he said was rendered unintelligible.

Meanwhile, Armstrong had tilted the MESA down past horizontal and pulled a lanyard to remove the thermal insulation blanket to expose the stowed apparatus. ‘‘Houston, I have the insulation off the MESA now, and the MESA seems to be in good shape.’’ Turning his attention to the television camera, he announced, ‘‘I’m going to change lenses on you.’’ As installed, the camera had a lens that provided an 80-degree field of view. He retrieved one with a 35-degree field of view from a slot of the MESA and put it on the camera, stowing the original lens. ‘‘Tell me if you’re getting a new picture.’’

‘‘That’s affirmative,” replied McCandless. ‘‘We’re getting a new picture. You can tell it’s a longer-focal-length lens. And for your information, all LM systems are Go.’’

‘‘We appreciate that,’’ Aldrin replied. ‘‘Thank you.’’

The commemorative plaque

Although each man had his individual checklist sewn onto the gauntlet of his left glove, several items were not listed. The unveiling of the commemorative plaque on the forward strut was such a late addition to the training that only Armstrong was

familiar with it. With both men standing alongside the ladder, in view of the television camera, he described the plaque, “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 AD. We came in peace for all mankind’. It has the crew members’ signatures and the signature of the President of the United States.’’ Measuring 9 by 7.625 inches with a thickness of 0.006 inch, it was made of #304 stainless steel with a brushed finish. The map and signatures were black epoxy in etched inscriptions. It was curved, conformal with the 4-inch radius of the strut but not actually in contact with it, being instead attached to the ladder by four spring clips, two on the third rung and two on the fourth rung. Armstrong hinged out and unlatched the sheet of stainless steel that had protected the plaque, in order to leave it exposed.

According to NASA Administrator Thomas O. Paine, the decision to make the plaque was a last-minute affair in which he and Wallis H. Shapley, an Associate Deputy Administrator, sketched the design, called in an artist to draw it properly, and sent the result to the White House for approval. However, Paine’s account is contradicted by Jack A. Kinzler, an engineer at the Manned Spacecraft Center. This account stated that when Robert R. Gilruth phoned seeking ideas for how to celebrate the landing, Kinzler suggested a plaque to be left on the descent stage. Kinzler and colleague David L. McCraw produced a prototype that featured a US flag of red, white and blue paints baked into the etched figure in stainless steel, together with the signatures of the crew and the name of the landing site – on the assumption this would be named. Gilruth replaced the flag by two hemispheres with continental outlines devoid of national boundaries, to identify the planet of origin. Kinzler said that, ‘‘Once the plaque concept was approved, NASA headquarters took it over.’’ When it was sent to the White House, Nixon changed the wording to past tense, and asked that his signature be added. Julian Scheer, head of the Public Affairs Office, has added a twist to the story, saying that NASA refused a suggestion by Nixon that ‘under God’ be inserted after the word ‘peace’.[37] The plaque’s design was made public shortly prior to launch. The astronauts had not been involved in the project, but felt it was tastefully done.

‘‘Are you ready for the camera?’’ Armstrong asked.

Although Aldrin was scheduled to use the Hasselblad soon, he decided not to take it yet, ‘‘No. I’ll get it later.’’ He was closely following the checklist, and the next item was to relocate the television camera, ‘‘You take the television on out.’’

Having pulled a strap on the MESA to release the tripod on which he was to mount the television camera, Armstrong prompted, ‘‘Would you pull out some of my cable for me, Buzz?’’

‘‘How is the temperature on there?’’ Aldrin asked, as he drew the cable from a dispenser on the MESA. A temperature-sensitive patch on the television camera was designed to darken with increasing temperature; it was still white, indicating that the camera had not overheated while being tested prior to the deployment of the MESA.

‘‘The temperature of the camera is showing ‘cold’,’’ Armstrong reported. He transferred the camera from the MESA to the tripod, and set off with it northwest, dragging the cable out as he went. On the way, something shiny on the bottom of a small crater attracted his attention. It was later concluded that this was a piece of glass, formed by the heat of a high-speed impact melting the regolith. In fact, there are two types of crater, ‘primary’ and ‘secondary’, with the primary produced by the impact of an object from space at cosmic velocity, and the secondary by the fall of ejecta issued by another impact. Since ejecta expelled faster than about 1.5 miles per second will escape the Moon, the speed of a secondary impact is necessarily at least an order of magnitude lower than that of a primary, and because kinetic energy is proportional to the square of the velocity, the energy of a primary strike for a specific mass greatly exceeds that of a secondary, and is sufficient to melt and fuse regolith.

Seeing Armstrong pause, Aldrin pointed out that there was more of the cable in the dispenser. ‘‘No, keep going. We’ve got a lot more, although it’s getting a little harder to pull out.’’

‘‘How far would you say I am, Buzz?’’

‘‘Oh, 40, 50 feet.’’ Then Aldrin suggested that Armstrong give the audience a panoramic view. ‘‘Why don’t you turn around and let them get a view from there, and see what the field of view looks like?’’

‘‘Okay,’’ Armstrong agreed.

‘‘You’re backing into the cable,’’ Aldrin warned, on seeing that Armstrong was at risk of entangling his feet in the cable. ‘‘Turn around to your right; that would be better.’’

‘‘I don’t want to go into the Sun if I can avoid it,’’ Armstrong pointed out. Now that he was in full sunlight, he was taking care not to point the camera towards the Sun because flooding it with harsh sunlight would undoubtedly damage it.[38] He set the tripod down 55 feet northwest of Eagle. “I’ll just leave it sitting like that, and walk around it.’’ Once in position, he inspected the lines inscribed on the top of the camera body to indicate the angular field of view of the lens. “Houston. How’s that field of view?’’

“We’d like you to aim it a little bit more to the right,’’ McCandless instructed. Armstrong adjusted the camera. “A little bit too much to the right! Can you bring it back left about 5 degrees?’’

“Do you think I ought to be farther away, or closer?’’ Armstrong asked once it was lined up on Eagle, showing Aldrin, who, having advanced to the next item on his checklist, was configuring the MESA for sampling activities.

“You can’t get much further away,’’ Aldrin pointed out, having pulled out all the cable.

Television panorama

Armstrong now set about moving/aiming the camera to give the audience a series of views around the horizon. The image became a blur while the camera was in motion, and cleared when he set it down. “That’s the first picture in the panorama,’’ Armstrong announced. “It’s taken just about north-northeast. Tell me if you’ve got a picture, Houston.’’

“We’ve got a beautiful picture, Neil,’’ McCandless confirmed.

He moved the camera further around the horizon. “Okay. Here’s another good one.’’ The horizon was featureless, but there was a lot of detail in the foreground. “Now this one is right down-Sun, due west, and I want to know if you can see an angular rock in the foreground sticking up out of the soil.’’

“We see a large angular rock in the foreground,’’ McCandless confirmed, “and it looks like there is a much smaller rock a couple of inches to the left of it.’’

“And about 10 feet beyond that is an even larger rock that’s very rounded,’’ said Armstrong. “The closest rock is sticking out of the soil about 1 foot; it’s about 18 inches long and about 6 inches thick, but is standing on edge.’’ Armstrong was spending a lot of time on this panorama because he believed on this first landing the geologists would welcome a view of the site.

“We’ve got this view, Neil,’’ McCandless prompted.

Armstrong moved the camera again, “This is straight south.’’

“Roger,’’ McCandless replied. “And we see the shadow of the LM.’’

“The little hill just beyond the shadow of the LM is a pair of elongate craters.’’ There were two craters aligned in an east to west direction to the southwest of the vehicle. “Probably the pair together is about 40 feet long and 20 feet across, and they’re probably 6 feet deep. We’ll probably get some more work in there later.’’ Armstrong returned the camera to face Eagle, where Aldrin was still working at the MESA. He had attached to the edge of the MESA the teflon bag in which they were to place samples prior to stowing them in a rock box, and had raised a table on which a box was to be mounted for access; in their stowed positions the boxes were recessed into the MESA pallet. After some adjustments to the pointing, Armstrong left the television camera viewing Eagle and the area immediately to its front. There was an 8-foot-diameter deployable S-Band dish with its own tripod stowed in a compartment in the front-left quadrant of the descent stage, but since erecting this would take 20 minutes this was to be done only if Houston deemed the quality of the transmission using the smaller dish of Eagle’s high-gain antenna to be unsatisfactory, which was not the case.

Having unstowed the Solar Wind Collector (SWC) from the MESA, Aldrin moved out to deploy it a short distance due north of Eagle. The experiment was a sheet of exceptionally clean aluminium on a staff that was to be positioned facing the Sun to soak up solar wind particles, particularly ions of helium, neon and argon (all of which were unreactive ‘noble’ elements in the Periodic Table). After Aldrin had extended the aluminium staff, he pulled out and locked the roller at the top, then drew down the 140-centimetre-tall and 30-centimetre-wide sheet from the roller and hooked it to a catch at the lower end of the staff.8 He found it difficult to drive the staff into the ground because (as had been noted by Armstrong while collecting the contingency sample) the finely grained surface material became consolidated at a depth of 4 or 5 inches. The sheet was to be rolled up at the end of the moonwalk and returned to Earth. Because it was to be analysed by a laboratory in Switzerland, the experiment was also known as the ‘Swiss flag’. On his way back from the television camera, Armstrong took several Hasselblad pictures of Aldrin with the experiment.

Aldrin observed that although the imprints left by their boot were generally only a fraction of an inch deep, their boots penetrated several inches where the loose material was piled up on the rims of small craters, and he wondered whether there was a correlation between the loose consistency and the change of slope. He had also noticed that when the toe of his boot penetrated the loose material at a shallow angle, it tended to displace a ‘slab’ of material as if it were solid, which, of course, it was not. A similar effect had been observed while pushing the surface material using the robotic arm of a Surveyor lander. Armstrong added an observation of his own, ‘‘I noticed in the soft spots where we leave foot prints nearly 1 inch deep, the soil is very cohesive, and will retain a slope of probably 70 degrees along the side of the foot prints.’’ These were welcome ‘soil mechanics’ observations.

Clifford E. Charlesworth was appointed as lead flight director for Apollo 11. Cool headed with an easy smile, he had been nicknamed the Mississippi Gambler by the flight controllers on account of the fact that, although he always appeared relaxed, he was focused and confident. As planning firmed up in early 1969, he shared the principal tasks among the available flight directors. Of the eight major phases of the mission, five had either been demonstrated by Apollo 8 or soon were to be by Apollo 10, and the three unrehearsed phases were the powered descent to the lunar surface, the moonwalk, and the lunar liftoff. As, by Apollo 11, Charlesworth would be most familiar with the Saturn V, he took launch on through to the translunar injection manoeuvre, plus the subsequent surface excursion. Eugene F. Kranz had most experience with the LM, including its unmanned test on Apollo 5 and manned test on Apollo 9, and was therefore assigned the lunar landing and transearth injection manoeuvre. As Glynn S. Lunney would have been to the Moon twice, both times focusing on the CSM, he was given responsibility for the lunar liftoff and rendezvous. Gerald D. Griffin and Milton L. Windler were assigned to other miscellaneous tasks. The flight directors met the branch chiefs of the flight control division to create their teams of flight controllers, balancing their individual areas of expertise to each phase of the mission.

While Apollo 11 had been in Earth orbit it had been able to communicate through the standard facilities of the Manned Space Flight Network, but once it had set off for the Moon NASA added in the large antennas of the Deep Space Network at Goldstone in California, Madrid in Spain and Canberra in Australia, which, being located at 120-degree intervals in longitude, provided continuous communications. Ron Evans, the CapCom on the ‘graveyard’ shift, never had occasion to talk to the crew. Biomedical telemetry indicated that the astronauts had been active for some time when McCandless made contact. ‘‘Apollo 11, this is Houston.’’

‘‘Good morning, Houston,’’ replied Armstrong immediately.

As flight day 2 began, almost 23 hours into the mission and with Houston time approaching 8 am on Thursday, 17 July, Apollo 11 was 93,085 nautical miles from Earth and its velocity had slowed to 5,638 feet per second.

McCandless immediately read up the flight plan updates and the status of the spacecraft’s consumables. As part of the post-sleep checklist, Collins gave a crew status report: he and Armstrong had slept for 7 hours, but Aldrin had gained only 5.5 hours. While the crew freshened up and prepared breakfast, McCandless read a selection of lighthearted news provided by the Public Affairs Office. ‘‘From Jodrell Bank, England, via Associated Press: The big Jodrell Bank radio telescope stopped receiving signals from the Soviet Union’s unmanned moonshot at 5.49 Eastern Daylight Time today. A spokesman said it appeared Luna 15 ‘had gone beyond the Moon’. Another quote from a spokesman for Sir Bernard Lovell, Director of the Observatory: ‘We don’t think it’s landed.’ Washington, United Press International: Vice President Spiro T. Agnew has called for putting a man on Mars by the year 2000, but Democratic leaders replied that priority must go to needs here on Earth. Agnew, the ranking government official at your launch, apparently was speaking for himself, and not necessarily for the Nixon administration. Laredo, Texas, AP: Immigration officials in Nuevo Laredo announced, Wednesday, that hippies will be refused tourist cards to enter Mexico unless they take a bath and get haircuts. Huberto Cazaras, Chief of Mexican Immigration in Nuevo Laredo, said authorities in popular tourist spots had registered complaints about the hippies. Next is from UPI in Washington: The initial reaction to President Nixon’s granting of a holiday, Monday, to Federal employees so they can observe a national day of participation in your lunar landing was one of surprise. Rodney Bidner, AP, London: Europe is Moon-struck by your mission. Newspapers throughout the continent filled their pages with pictures of the Saturn V rocket lifting off to forge Earth’s first link with its natural satellite. The headline-writers taxed their imaginations for words to hail the feat. ‘The greatest adventure in the history of humanity has started’, declared the French newspaper Le Figaro. It devoted 4 pages to reports from the Cape and has diagrams of the mission. The tabloid Paris Jour proclaimed, ‘The whole world tells them, bravo’. The communist daily L’Humanite led with the launch picture, and devoted its entire back page to an enthusiastic report describing the countdown and launch, the astronauts’ wives and families, and some background for the lunar activities. Hempstead, NY: Joe Namath officially reported to the New York Jets training camp at Hofstra University, Wednesday, after a closed-door meeting with his team mates to discuss his differences with the pro-football commissioner, Peter Rozelle. London, UPI: The House of Lords was assured, Wednesday, that a midget American submarine would not ‘damage or assault’ the Loch Ness monster. Lord Nomay said he wanted to be sure anyone operating a submarine in the Loch ‘would not subject any creatures that might inhabit it to damage or assault’. He asked that the plan to take a tissue-sample with a retrievable dart from any monster be done without damage and disturbance. He was told that it was impossible to say if the 1876 Cruelty to Animals Act would be violated unless and until the monster was found.’’

And with that, it was back to work. McCandless provided feedback to Collins regarding the difficulties he had encountered in locating the substellar point during the P23 sextant sightings of stars during the previous day’s deep-space navigation. At the 24-hour point, Collins halted the PTC, Houston uplinked a new state vector based on tracking by the Manned Space Flight Network, and Collins performed a P52 to realign the platform prior to recalibrating the sextant as a preliminary to resuming the P23 exercise. Now at a distance of 102,436 nautical miles, Earth had a much smaller angular diameter and its horizon was sharper. He started with the star Alpheratz because it was near the horizon, simplifying the task of checking whether the automatic alignment correctly identified the star’s substellar point. Although the axis of measurement was clearly perpendicular to the horizon, the star itself was not apparent. ‘‘Everything looks beautiful except there is no star in sight. It is just not visible.’’

McCandless announced the belated realisation that the star was occulted by the body of the LM, and recommended a different attitude.

While Collins performed the manoeuvre, Jim Lovell called, ‘‘Is the commander aboard?’’

‘‘This is the commander,’’ replied Armstrong.

‘‘I was a little worried. This is the backup commander still standing by. You haven’t given me the word yet. Are you Go?’’ Lovell was reminding Armstrong that if he was not feeling up to the mission, he was willing to take his place – in jest, of course, as an exchange was impossible following launch.

‘‘You’ve lost your chance to take this one, Jim.’’

‘‘Okay. I concede.’’

Collins now announced that in the second attitude the axis of measurement was rotated 90 degrees from that needed to measure the elevation of the star. “I’m going to hold right here for your next suggestion.’’

Charlesworth decided that they should curtail the P23 exercise, and prepare for midcourse correction 2. Initiated at 026:44:57.92 at a distance of 109,245 nautical miles from Earth while travelling at 5,033 feet per second, the 2.91-second burn of the SPS engine slowed the spacecraft by 20.9 feet per second to reduce the closest approach to the Moon from the initial 175 nautical miles to the desired 60 nautical miles.

“We saw about 87 or 88 psi chamber pressure,’’ reported Armstrong, referring to the SPS. This was rather low. “I’d like you to look at that on the ground.’’

McCandless said he would pass on the result of an engineering analysis of the telemetry. Two hours later, he confirmed that the chamber pressure had been stable at 94 psi, which was acceptable. Further analysis established that the performance of the engine during both burns matched that of the acceptance trials, and that the discrepancy was merely inaccurate calibration of the onboard gauge.3 As the crew worked through the post-burn checklist, McCandless said, “we played the recorded television back last night, after you all turned in for your rest period, and the pictures came out quite well’’.

Having abandoned the P23 exercise, Collins began to re-establish PTC. He was impressed that the rotational axis had remained stable through their sleep period. While the computer worked to damp out oscillations, Lovell provided angles for the high-gain antenna, which was one of Aldrin’s tasks. “You may have to repeat some of that, James,’’ Collins warned. “We have got a LM guy taking care of the high – gain right now, and he’s got his head out the window.’’

“I understand,’’ said Lovell. “I had trouble on Gemini 12 with him, too.’’

“Hey, Jim,’’ Aldrin called, “I’m looking through the monocular now and, to coin an expression, the view is just beautiful. It’s out of this world. I can see all the islands in the Mediterranean – Majorca, Sardinia and Corsica. There is a little haze over the upper Italian peninsula, some cumulus clouds out over Greece. The Sun is setting on the eastern Mediterranean now. The British Isles are definitely greener in colour than the brownish green on the Iberian peninsula.’’

“Do you find that the monocular is any good to you, Buzz?’’ Lovell asked.

“It would be nicer if it had another order of magnitude of power on it. Of course, it has a tendency to jiggle around a little bit, and you might want to have some sort of a bracket. There is an anticyclone down in the southern hemisphere, southeast of Brazil, and the diameter of it must be over 2,000 miles across.’’ Then he reported something he had not expected. “I’ve got a comment about the point on the Earth where the Sun’s rays reflect back up toward us. In general, the colour of the oceans is mostly uniform and it’s bright and darker blue except for this circular area that’s about one-eighth of an Earth’s radius in diameter in which the blue of the water turns a greyish colour.’’

Houston would revisit this issue at the start of flight day 4.

“We noticed the same thing on Apollo 8. It’s very similar to looking at a light shining on something like a billiard ball or a bowling ball; you get this bright spot in the blue of the water, and that turns it to sort of a greyish colour.’’ The technical term for this phenomenon was specular reflection.

Aldrin had also been experimenting. “Hey, Jim, the best way to get a steady view through the monocular is to steady it out and set it close in front of your eye, and then you kind of float up next to it so that you’re not touching it at all.’’

“How does it feel to be airborne again, Buzz?’’ Lovell asked.

“I’ve been having a ball floating around inside here – it’s like being outside, except more comfortable.’’

“It’s a lot bigger than our last vehicle,’’ Lovell observed, referring to Gemini.

Collins, the chauffeur, joined in the banter. “Oh, yes. It’s nice. I’ve been very busy so far. I’m looking forward to taking the afternoon off. I’ve been cooking, and sweeping, and almost sewing, and you know, the usual little housekeeping things.’’

“It’s very convenient the way they put the food preparation system right next to the navigation station,’’ Lovell said, implying that Collins could do everything from his position in the lower equipment bay.

“Everything is right next to everything else in this vehicle,’’ Armstrong noted, meaning that the designers had done well to squeeze everything into such a small volume.

With the spacecraft’s attitude stabilised perpendicular to the ecliptic, Collins initiated the PTC roll. As he did so, they crossed the point where they were equi­distant between Earth and Moon, 112,386 nautical miles from each. However, as they were still slowing down, they were by no means half-way in terms of time. As Earth drifted by, Collins took the opportunity to take a look for himself. “I’ve got the world in my window for a change, and looking at it through the monocular it’s really something. I wish I could describe it properly. The weather is very good. South America is coming around into view, and I can see all the way down to the southern tip of Tierra del Fuego.’’ With that, Earth drifted from his field of view. Aldrin promptly pointed out that he was waiting to pick it up in the sextant for a magnified view.

“It sounds like one of those rotating restaurants!’’ McCandless said.

The mention of a restaurant prompted them to start lunch.

“Is that music I hear in the background?’’ McCandless asked.

“Buzz in singing,’’ Collins replied.

“Houston,’’ Armstrong called, “we’re just looking at you out our window here, and it looks like there’s a circulation of cloud that just moved east of Houston over the Gulf and Florida area. Did you have any rain this morning?’’

“Our report from outside says it’s raining now. It looks like you’ve got a pretty good eye for the weather there!’’

“Well, it looks like it ought to clear up pretty soon,’’ Armstrong advised.

After lunch, Armstrong and Aldrin reviewed LM activities, and Collins did the routine chores of purging contaminants from the fuel cells, topping up the charges of the batteries, dumping waste water and exchanging the lithium hydroxide filter that absorbed the carbon dioxide of the astronauts’ exhalation.

A telecast was scheduled for later in the afternoon, and the astronauts decided to conduct another system test without announcing the fact. After several minutes, McCandless called, “Eleven, Houston. Goldstone reports that they are receiving a television picture coming down. It’s a little snowy, but a good television picture.” “We’re just testing the equipment up here,’’ Armstrong explained.

“Ask if they can read the numbers,’’ Collins prompted. The view was showing the DSKY, and he wanted to know if the display was readable, as a measure of the image quality.

“What numbers are you referring to?’’ McCandless asked.

“Well,” Collins sighed, “I guess if they can’t see any numbers, it’s kind of a lost cause!’’

“We want to know what numbers, before we ask them,’’ McCandless said. Collins realised the misunderstanding. “I’m showing them the DSKY.’’

After conferring, McCandless reported, “They can read the numbers, ‘VERB’, ‘NOUN’, ‘PROGRAM’, and the ‘COMPUTER ACTIVITY’ light is flashing. ‘‘Very good. Thank you.’’

Without providing commentary, the crew, handing the camera back and forth, aimed it through window 4 at the overhead window of the LM, through window 2 at the docking target, and then provided close-up views of the main control panel of the command module.

The picture was snowy because it was transmitted through the omnidirectional antennas, which could not provide the signal strength of the high-gain antenna, and the spacecraft was just about at the limit for transmitting television in this manner. For the telecast due later in the day they were to halt PTC in order to maintain the high-gain antenna pointing at Earth.

As the flight control teams switched shifts, McCandless handed over to Duke. ‘‘How’s the White Team today?’’ Collins enquired.

‘‘Bright-eyed and bushy-tailed.’’

Collins, on the left side, braced his arms against the bulkhead ‘above’ his head to maintain his feet against the wall of the lower equipment bay. ‘‘Have you got any medics down there watching telemetry? I’m trying to do some running in place here, and I’m wondering just out of curiosity whether it brings my heart rate up.’’

‘‘We see your heart beating.’’

Armstrong, in the centre, joined in.

‘‘Look at Armstrong’s and Collins’s and see if they go up any,’’ Collins called. ‘‘We’re running in place up here. You wouldn’t believe it.’’

‘‘I’d like to see that sight,’’ Duke replied. ‘‘Why don’t you give us a television picture of that?’’

‘‘I think Buzz is trying,’’ Collins said. ‘‘Have you got it?

‘‘It’s coming in at Goldstone, but we don’t have it here in the Control Center.’’ ‘‘I’m afraid this isn’t going to help out the PTC very much!’’ Collins reflected. ‘‘I don’t know if it’s a vibration or what it is, but it makes the pitch and yaw rate needles on the FDAI oscillate a little bit where we jump up and down.’’

‘‘Goldstone say they see you running there, Mike. You’re about a 96 heart beat now.’’

“That’s about all that’s reasonable, without getting hot and sweaty.” They had only one change of clothes, one for the trip out and the other for the trip home.

Aldrin then aimed the camera through window 5 at Earth. At 31 hours into the mission, Apollo 11 was 121,158 nautical miles out, and travelling at 4,613 feet per second.

“For this television program coming, you might give some thought to how you want us to stop PTC for the best high-gain angle,’’ Collins suggested. Also, it’d be nice if you could stop us at such an attitude that we’ll have Earth out of one of our windows.’’

“Boy,” announced Aldrin, “you sure get a different perspective of the cabin in zero-g. Right now, Neil has got his feet on the forward hatch, and not only can he reach all five windows with his arms but he can also reach down into the lower equipment bay.’’

“Sounds like Plastic Man to me,’’ laughed Duke.

“I’m hiding under the left-hand couch, trying to stay out of his way,’’ Collins chipped in.

“Good idea, Mike,’’ Duke agreed. He then specified an attitude for the telecast that would both provide a good line of sight for the high-gain antenna and position Earth in the left-hand window. In fact, since the recommended attitude would hold the primary axis perpendicular to the ecliptic, Collins would be able to establish it simply by halting the roll.

When Duke said the weather over the Houston area had cleared, as Armstrong had predicted, Collins took a look through the sextant. “I can see that the coastline is clear; those clouds have moved inland. It looks like the southeastern part of the country is socked in, but California looks nice. The San Joaquin Valley shows up as a real dark spot with a lighter brown on either side of it. You can’t tell that it’s green; it looks just sort of dark grey, or maybe even real dark blue.’’

“How does the Mojave look?’’ Duke asked. “Is it clear?’’

“Yes – as usual.’’

“Can you pick out Edwards in the sextant?’’

“I can see an F-104 taxiing out for takeoff on the runway,’’ Collins joked.

“That’s super!’’

“They almost always have a 104 taxiing!’’ Collins explained.

“Hey, Charlie,’’ Aldrin called, “what’s the latest on Luna 15?’’

“TASS reported this morning that it has entered orbit close to the lunar surface, and everything seems to be functioning normally.’’ Nevertheless, the Russians had not confirmed that Luna 15 was to attempt to land, let alone that it was to scoop up a sample for return to Earth; they never announced missions in advance.

The flight plan called for a telecast starting at an elapsed time of 34 hours (i. e. 6.32 pm in Houston) and lasting for 15 minutes. After terminating PTC, they began to transmit, and this time Mission Control was configured to view ‘live’. The telecast began with a long shot of Earth. ‘‘This is Apollo 11, calling in from about 130,000 miles out,’’ Armstrong announced. ‘‘We’ll zoom our camera in slowly and get the most magnification we can.’’ Although the quality of the image using the high-gain antenna was excellent, Duke requested a description. ‘‘We’re looking at the eastern

Pacific Ocean, and in the top half of the screen we can see North America, Alaska, United States, Canada, Mexico and Central America, but South America becomes invisible just off beyond the terminator, or inside the shadow. We can see the oceans with a definite blue cast; white bands of major cloud formations across the Earth; the coastline of the western US; the San Joaquin Valley; the Sierra range; the peninsula of Baja California; and some cloud formations over the southeastern US. There’s one definite mild storm about 500 to 1,000 miles southwest of Alaska, and another very minor storm at the south part of the screen, at probably 45 degrees or more southern latitude. We can pick out the browns in the landforms pretty well. Green doesn’t show up very well, but there is some showing along the northwestern coast of the United States and Canada.’’

“The whites are distinct, but on this monitor the landmasses appear to be just a darker greyish colour rather than a brown,’’ Duke said.

“It’s true that we don’t have the depth of colour at this range that we enjoyed at 50,000 nautical miles out,’’ Armstrong said. “But the oceans still are a definite blue and the continents are generally brownish in cast, although they’re tending more towards grey now than they were at the closer range.’’

“I’ve just looked at another monitor,’’ Duke announced, “and sure enough, the browns are coming in a lot more distinctly on the Eidophor that we have up on our screen in the Control Center.’’

On the front wall of the Mission Operations Control Room there was a 10-foot by 20-foot main screen in the centre, with two 10-foot by 10-foot screens on each side. Television could be displayed using an Eidophor projector, a technology that was developed in the 1950s to create theatre-sized television images. Its optical system was similar to a conventional movie projector, but instead of spooling film it had a slowly rotating disk covered with a thick oil, and a scanning electron beam created electrostatic charges on the oil, deforming its surface in such a way that when light was passed through the oil it produced an image with light and dark areas. As the disk rotated, a blade discharged and smoothed the surface, readying the oil for the next cycle. The modern Eidophors could show colour television using sequential red, green and blue projections.

At this point, Collins, who was holding the camera while Armstrong provided commentary, interjected, “Okay, world, hold on to your hat. I’m going to turn you upside-down.’’ He slowly rotated the camera through 180 degrees.

“That’s a pretty good roll,’’ Duke complimented.

“I’m making myself seasick, Charlie. I’ll just put you back rightside-up where you belong.’’ He completed the circle.

“We would like to see some smiling faces up there, if you could give us some interior views,’’ Duke prompted. “I’m sure everybody would like to see you.’’ The astronauts’ wives especially.

The interior lights had been switched off in order to prevent reflections on the window through which the camera was viewing. Once the lights were reactivated, the camera was swung inside to display Collins. “Hello there sports fans. Buzz is doing the camera work now. I would have put on a coat and tie if I’d known about this ahead of time.’’

“Is Buzz holding your cue cards for you?” Duke enquired.

“We have no intention of competing with the professionals, believe me. We’re very comfortable up here, though. We have a happy home. There’s plenty of room for the three of us, and I think we’re all learning to find our favourite little corner to sit in. Zero-g is very comfortable, but after a while you get to the point where you sort of get tired of rattling around and banging off the ceiling and the floor and the side, so you find a corner somewhere and put your knees up or something like that to wedge yourself in.’’ Armstrong tended to remain in a couch and Aldrin spent much of his time in the lower equipment bay, but Collins, who was operating the CSM, was for ever flitting about.

The view switched to Armstrong. “It’s a real good picture we’re getting here of Commander Armstrong,’’ Duke complimented.

“Neil’s standing on his head again, trying to make me nervous,’’ said Collins. Armstrong had his feet up by the apex. “Directly behind his head are our optical instruments, the sextant and the telescope that we use to take sightings with.’’

“It’s a beautiful picture,’’ Duke enthused. “The clarity is outstanding.’’ In fact, the quality was even better than on Apollo 10. Unfortunately, this led the audience to expect to view the moonwalk in similar style.

Aldrin aimed the camera at one of his star charts, which he had taped up over window 5 to serve as a sunshade.

“He doesn’t really need the charts,’’ Collins noted. “He’s got them memorised. They’re just for show.’’ Aldrin had even brought a slide rule in case the computer should fail!

Aldrin explained that with Earth visible in one side window and the Sun in the other, the spacecraft’s current attitude was perpendicular to the ecliptic. From their viewpoint, the Moon was approaching the Sun in the sky and facing its darkened hemisphere towards them, which was why they could not show the audience their destination. He handed the camera to Armstrong, grasped wall handles using both hands, and gave a demonstration of weightless exercises.

Pointing out that it was approaching dinner time in Houston, Collins went to a locker in the lower equipment bay. “We’ll show you our food cabinet here.’’

“We see a box full of goodies there,’’ said Duke.

“We’ve got all kinds of good stuff,’’ Collins said as he pointed to the groups of packets. “We’ve got coffee up here at the upper left; and various breakfast items – like bacon in small bites; beverages like fruit drink; and over in the centre part we have all kinds of things. Let me pull one out here, and see what it is.’’ He read the label. “Would you believe you’re looking at chicken stew? All you have to do is add 3 ounces of hot water and wait for 5 or 10 minutes. Now we get our hot water out of a little spigot up here with a filter on it that filters out any gases that may be in the drinking water, and we just stick the end of this little tube in the end of the spigot and pull the trigger three times for 3 ounces of hot water and then mush it up and slice the end off it and there you go, beautiful chicken stew.’’

“Sounds delicious,’’ Duke said.

“The food so far has been very good,’’ noted Collins. “We couldn’t be happier with it.’’ Because that part of the cabin was dimly illuminated, he had been using a small torch to show the food packs. He showed how he could leave the torch in a stable orientation to illuminate the locker in order to have both hands free to sort through the packets. “The problem is that no matter how carefully you let go, you bump it just a tiny little bit and set it in motion.” He tapped one end of the slowly rotating torch with his finger, and set it spinning as a demonstration of rotation in weightlessness.

Aldrin pointed out that in preparing for the telecast, they had realised the cable for the television camera (which they had not seen in training) was probably long enough to run through the tunnel into the LM, and said that they intended to try to televise the LM inspection scheduled for the third day. Duke said that would be a great idea.

Armstrong pointed the camera back at Earth and operated the zoom to make it diminish. “This is Apollo 11 signing off.”

“Thank you for the show,” said Duke. At about 35 minutes, it had lasted twice the scheduled duration.

As they had not departed from an attitude perpendicular to the ecliptic, all that Collins needed to do to reinstate PTC was to resume the roll.

On 31 January 1969 Apollo Program Director Samuel C. Phillips asked Robert R. Gilruth of the Manned Spacecraft Center, Wernher von Braun of the Marshall Space Flight Center and Kurt H. Debus of the Kennedy Space Center to suggest symbolic activities that might be undertaken on the first lunar landing mission that would illustrate international agreements regarding the exploration of the Moon. The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space that was signed by the United States and the Soviet Union on 27 January 1967 (and, incidentally, witnessed by some of the astronauts, among them

The SWC sheet was designed in metric units, so these have been used here to enhance fidelity.

Neil Armstrong) stated, in part, that the spacefaring powers agreed not to stake territorial claims on celestial bodies. When NASA proposed that the flag of the United Nations be raised, this was rejected by Congress, which directed that the US flag be flown. Phillips proposed that they also either raise the flag of the United Nations alongside the American flag, place decal flags of the member nations of the UN on the descent stage, or just deposit an appropriate information capsule on the surface.[39] However, Congress ordered that only the flag of the United States be raised. In order to preclude any manufacturer claiming to have made the flag used on the Moon, George M. Low ordered that a 3-foot-by-5-foot Stars and Stripes be purchased (at the average price of $3) from every official supplier, that their labels be removed, and that a secretary select a flag at random; the other flags would not go to waste, because if ever there was a mission to prompt the waving of a flag this would be it!

Having returned to Eagle, Armstrong and Aldrin retrieved the flag assembly from stowage in a thermal shroud by the left-hand ladder rail. They then set off northwest, in the general direction of the television camera, Aldrin carrying the lower part of the aluminium staff and Armstrong the upper part of the staff with the crossbar attached at its top by a locking hinge, incorporating the flag itself. Once they were in position, Armstrong rotated the crossbar into position and the two men grasped opposite ends of the telescoping rod in order to draw it out, but it became stuck just short of its full extension.

At this point Columbia appeared around the limb. “How’s it going?” asked Collins. Joan Aldrin sympathised with him, “He doesn’t know what’s going on, poor Mike!’’

“The EVA is progressing beautifully,” McCandless replied. “I believe they are setting up the flag now.’’

“Great!” Collins said.

“I guess you’re about the only person around that doesn’t have TV coverage of the scene,’’ McCandless consoled.

“That’s all right,’’ Collins insisted. “I don’t mind a bit. How is the quality of the television?’’

“Oh, it’s beautiful, Mike. It really is,’’ McCandless assured.

“Oh, gee, that’s great!’’ said Collins. “Is the lighting half-way decent?’’

“Yes, indeed,’’ McCandless confirmed.

Having accepted that the crossbar would deploy no further, Armstrong set out to drive the lower section of the staff into the ground. As in the case of the staff of the SWC, the ground resisted penetration. Frustratingly, the surficial material gave little lateral support to hold the staff upright. On placing the flag assembly on top of the staff, Aldrin stepped back to salute and the flight control team stood, cheered and applauded.

“They’ve got the flag up now,” McCandless informed Collins, “and you can see the Stars and Stripes on the lunar surface!’’

“Beautiful,” replied Collins.

While Armstrong held the staff, Aldrin gripped the top and bottom of the flag and attempted to straighten it, in vain. They left it with a ‘permanent wave’ which, in retrospect, gave it a more natural appearance than if they had been able to draw it out totally flat. To finish off, Armstrong snapped two pictures of Aldrin standing by the flag.

Moving to his next checklist assignment, Aldrin set about evaluating modes of mobility. To enable the engineers to monitor his progress, he was to perform this exercise in front of the television camera. When asked, McCandless verified that he was in the field of view. He tested (1) a ‘loping gait’ in which he alternated his feet; (2) a ‘skipping stride’ that always led with the same foot; and (3) a ‘kangaroo hop’ in which both feet acted together. The conventional walking gait proved to be the most effective. On Earth he could easily halt his motion with a single step, but on the Moon it took several steps to slow down because the ratio of mass-to-weight had changed by a factor of 6. Similarly, changing direction while in motion had to be done in stages, stressing the outside leg in order to force the turn. As Aldrin paraded in front of the television camera, his wife laughed so much that her eyes wept. Pat Collins, watching with Barbara Gordon and Sue Bean, was amused by his antics. Jan Armstrong, who was ticking off items on her list, doubted they would achieve all of their assigned tasks in the time available.

Meanwhile, Armstrong had dismounted the Hasselblad and placed it on the MESA in order to start to prepare the equipment with which he was to collect what field geologists call a ‘bulk’ sample of the loose ground mass with embedded rock fragments.

A long-distance phone call

‘‘Tranquility Base, this is Houston,’’ McCandless called formally. ‘‘Could we get both of you on the camera for a minute, please.’’

‘‘Say again, Houston,’’ said Armstrong.

After repeating the request, McCandless added, ‘‘Neil and Buzz, the President of the United States is in his office now and would like to say a few words to you.’’

‘‘That would be an honour,’’ Armstrong said.

Richard Nixon had been watching them on television with Frank Borman in his private office in the White House. After the flag had been raised, Nixon went next door to the Oval Office to place a telephone call to the lunar surface. With a camera set up in the Oval Office, the television networks presented this historic call in split­screen fashion. Deke Slayton had alerted Armstrong that at some time during the moonwalk (the obvious moment being just after the flag was raised) they might receive a ‘‘special communication”, which they both took to mean a call from Nixon. However, it came as a surprise to Aldrin.

‘‘Go ahead, Mr President,’’ said McCandless.

‘‘Neil and Buzz,’’ Nixon began, ‘‘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 have done. 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 tranquillity 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.’’ “Thank you, Mr President,’’ Armstrong acknowledged. “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 interest and a curiosity and a vision for the future. It’s an honour for us to be able to participate here today.’’

“And thank you very much,’’ added Nixon, “and I look forward – all of us look forward – to seeing you on the Hornet on Thursday.’’

“I look forward to that very much, sir,’’ replied Armstrong, signing off.

Both astronauts had remained in place throughout the call. Aldrin remained silent and left it to his commander to make the responses.

In the Collins house, Rusty Schweickart said there would be scientists around the world urging the astronauts to push on and collect some rocks. Indeed, Nixon was later criticised by some in the scientific community for having ‘wasted’ the limited time available to the astronauts. Aldrin, following his checklist, shuffled around repeatedly scuffing the surface with his boot to observe how the material dispersed. When sand on a terrestrial beach is scuffed, it disperses in an arc with some of the grains travelling further than others. On the Moon, in the absence of air-drag to sort the particles by size, all the grains landed at the same radius, which depended upon the impulse imparted and the weak lunar gravity. As this phenomenon marked a striking difference between training and reality, Aldrin found it fascinating. On returning to Eagle, Aldrin was struck by the sharpness of the vehicle’s shadow. On standing in sunlight and projecting his arm into the shadow, it seemed to vanish. Furthermore, as he recalled later, ‘‘The light was sometimes annoying, because when it struck our helmets from a side angle it would enter the face plate and make a glare that reflected all over it. As we penetrated a shadow we would get a reflection of our own face, which would obscure anything else. Once when my face went into shadow it took maybe 20 seconds before my pupils dilated out again and I could see details.’’

The original concept for Apollo 10 called for the spacecraft to enter lunar orbit and for LM-4 to undock, enter a slightly different orbit, return and redock as a test of operating in lunar orbit. In December 1968, however, the mission planning and analysis division of Mission Control successfully argued the case for putting the descent propulsion system through a realistic rehearsal in which the perilune would be lower. This would test the ability of the landing radar to lock onto the surface, with the illumination on the low passes exactly as it would be on the landing mission in order to document the primary site and identify landmarks on the approach route. Howard W. ‘Bill’ Tindall, the assistant division chief, had also suggested that the LM should initiate the powered descent and abort by ‘fire-in-the-hole’ staging, but this was not pursued. After three outstandingly successful manned missions, considera­tion was given to assigning Apollo 10 the landing mission. However, because LM-4 was incapable of landing – the software was not ready for either the simulator or the

vehicle, and in any case LM-4 was too heavy to carry sufficient propellant to lift off again – Apollo 10 commander Tom Stafford argued against waiting for LM-5. “There are too many ‘unknowns’ up there,” he insisted. “We can’t get rid of the risk element for the men who will land on the Moon but we can minimise it; our job is to find out everything we can in order that only a small amount of ‘unknown’ is left.’’ The plans, procedures, mission rules, manoeuvres, thermal regime and communica­tions would provide a high-fidelity rehearsal of the landing mission. On 24 March 1969 it was announced that Apollo 10 would conduct this dress rehearsal, and if it achieved its primary objectives then Apollo 11 would attempt to land.

One aspect of the Apollo 10 mission was to assess the operation, tracking and communications of two spacecraft in lunar orbit. Apollo 8 had confirmed that the mascons significantly perturbed the orbit of a spacecraft. By having Apollo 10 fly the profile planned for the landing mission, it would be possible to assess how the guidance and navigation system of the LM coped with these gravitational effects while making the low passes of the descent orbit. Apollo 10 lifted off on schedule on 18 May, and on the fifth day the LM separated in a circular parking orbit at an altitude of 60 nautical miles, entered an elliptical orbit with a 50,000-foot perilune, made two low passes, discarded the descent stage, and made a perfect rendezvous. The first low pass rehearsed an approach to ALS-2 (site ‘A3’, later 2P-6), and while the aim point itself was acceptable, the western end of the ‘landing ellipse’ was rougher, and Stafford told Armstrong that if he were to find himself coming in ‘long’, his best option might be to abort.

з

Preparations

SIMULATION

With Apollo 10 having mitigated the risks, Armstrong and Aldrin were able to focus their training on the powered descent and lunar lift off. However, because Apollo 10 had first call on the simulators until early May, Clifford Charlesworth initiated training in April with the Saturn V launch phase. Two months then remained in which to conduct the specialised training because, with a target launch date of 16 July, the most intensive training using the simulators would be completed about 10 days earlier in order to enable the crew and flight control teams to finish other activities. Simulation explored two basic scenarios: ‘nominal’ and ‘contingency’. The nominal part occupied only a few days, and defined the Go/No-Go decision points, the procedures, and the timings for the interactions between the crew and the flight controllers. The first full set of mission rules for Apollo 11 was issued on 16 May, but was preliminary pending methodical testing by simulation. Because the nominal powered descent was to last only 12 minutes, it was possible to perform many runs and debriefings during a single day’s training. While Apollo 10 was performing its rehearsal in lunar orbit, Armstrong and Aldrin were routinely landing by flying the nominal profile. Contingency training was designed to test how the crew and flight controllers dealt with departures from the nominal profile involving trajectory and systems problems. The Simulation Supervisor (SimSup) for the powered descent was Dick Koos, an early recruit of the Space Task Group to train control teams. As there were then no graduates with computer degrees, NASA had hired engineers with experience, and his background was the computerisation of ground-to-air missiles for the Army Missile Command at Fort Bliss, Texas. Koos and his five support staff occupied a glassed-in partition at the front of the Mission Operations Control Room, and their role was to develop realistic mission scenarios that would assess the mission strategy, rules and procedures, the knowledge and coordination of the individual flight controllers, the ability of the team as a whole to develop real-time solutions to technical difficulties, and generally to probe the psyches of everyone involved. It was considered that a fully trained team of flight controllers ought to be able to function as a single ‘mind’.

The first contingency training was on 10 June. A succession of runs introduced a

An hour after the telecast, Duke asked the crew to participate in an experiment using a laser. ‘‘If you have got Earth through any of your windows, or in the telescope, would you so advise?’’

‘‘I’ve got you in the telescope,’’ Collins replied.

‘‘We have a blue-green laser that is to flash at a frequency of on-for-a-second, off – for-a-second. It’s from the McDonald Observatory near El Paso, Texas, which should be just on the dark side of the terminator. Would you take a look and see if

you can see it.” Collins agreed. “McDonald reports there is a break in the clouds,” Duke announced a few minutes later, “and they’re beaming it through.” Observing nothing through the telescope, Collins switched to the magnifying sextant, with no better result. Armstrong joined him. Aldrin reported, “Neither Neil nor Mike can see it. We did identify the El Paso area, and there did appear to us to be a break in the clouds there.’’ However, at their distance from Earth, the beam would be just a few thousand feet across, and was very likely not illuminating the vehicle.

Half an hour later Duke signed off, “The White Team bids you good night.’’

“You earned your pay today, Charlie,’’ Aldrin said.

As the Black Team began the ‘graveyard’ shift, with Gerry Griffin standing in for Glynn Lunney as flight director, the astronauts finished miscellaneous chores, had supper, and settled down for their second sleep period, this time with Aldrin as the watch-keeper. By this time, Apollo 11 was 137,219 nautical miles from Earth, and travelling at 4,132 feet per second.