Category The First Men on the Moon

LUNAR SURFACE EXPERIMENTS

During a meeting in the summer of 1964 at Woods Hole, Massachusetts, the Space Science Board of the National Academy of Sciences listed basic questions relating to the Moon that ought to be studied either by spacecraft placed into lunar orbit or by instruments emplaced on the lunar surface.

On 19 November 1964, after tests conducted on an aircraft providing one-sixth gravity established that astronauts would be able to offload scientific instruments from the descent stage of the LM onto the lunar surface, the Manned Spacecraft Center began to study how instruments might be powered. It was decided that the best source would be a radioisotope thermal generator (RTG) in which heat was converted by thermocouples into electricity. The Grumman Aircraft Engineering Corporation of Bethpage, New York, which was developing the LM, was asked to give some thought to how an RTG might be packaged and carried. Grumman was also asked to develop a prototype for a container in which to return to Earth samples of lunar material. This would require to be carried on the exterior of the vehicle, accessed while on the surface, loaded, hermetically sealed, transferred into the ascent stage, and later passed through the tunnel into the command module and stowed for the flight home.

In January 1965 NASA undertook a time-and-motion investigation in order to assess how best to use the limited time that would be available to the first Apollo crew to land on the Moon. In May, a preliminary list of surface experiments was drawn up, and George E. Mueller, Director of the Office of Manned Space Flight, initiated a two-phase procurement process: the definition phase was to be done in parallel by a number of companies, one of which would be selected to develop the hardware for flight. In June the Manned Spacecraft Center set up the Experiments Program Office within its Engineering Development Directorate to manage all experiments for manned spacecraft, and Robert O. Piland, formerly deputy manager of the Apollo Spacecraft Program Office, was selected to head it. On 7 June Mueller approved the procurement of the Lunar Surface Experiments Package (LSEP) and assigned responsibility for its development to the Experiments Program Office. It was to be an RTG-powered suite of instruments that had to be able to be deployed

by two men in 1 hour, and was to transmit data to Earth for 1 year. Overall, it was envisaged as a passive seismometer to monitor moonquakes; an active seismometer that would detonate calibrated explosive charges in order to seismically probe the shallow subsurface; a gravimeter to measure tidal effects that might shed light on the deep interior; an instrument to measure the heat flowing from the interior; radiation and meteoroid detectors; and an instrument to analyse the composition of any lunar atmosphere. The instruments would be electrically connected to a central station that would transmit to Earth. Mueller specified that the package should be available for the first landing mission. On 3 August NASA announced that Bendix Systems, TRW Systems and Space-General Corporation had each been given a 6-month contract worth $500,000 to propose designs. On 14 October NASA contracted the General Electric Company to supply the RTG under the supervision of the Atomic Energy Commission. An instrument to investigate any lunar magnetic field was added to the suite on 15 December. By early 1966 the instrument suite had been renamed the Apollo Lunar Surface Experiments Package (ALSEP). On 16 March NASA Administrator James E. Webb decided that, in view of the company’s experience in developing experiments for automated lunar spacecraft, Bendix of Ann Arbor, Michigan, would receive the contract to design, manufacture, test and supply four ALSEPs (three flight units and one in reserve), the first of which was to be delivered no later than 1 July 1967.

Homer E. Newell, Associate Administrator for Space Science and Applications, wrote to Mueller on 6 July 1966, “the highest scientific priority for the Apollo mission is the return to Earth of lunar surface material’’, with the position of each sample being carefully documented prior to sampling. Newell recommended that on the first moonwalk the astronauts start by collecting an assortment of readily accessible samples (a ‘grab bag’ in the vernacular of field geology), deploy the ALSEP, and end with a ‘traverse’ to collect a number of ‘documented samples’, utilising a range of tools, including core tubes.

By the autumn of 1966 the magnetometer was having serious developmental problems, and the central data-processor was in a critical state. At the end of the year, NASA headquarters suggested that an instrument on the second ALSEP be brought forward as a replacement for the magnetometer, but as the scientists said that the magnetometer would be required to properly interpret the data from the other instruments, it was decided to develop a simpler magnetometer as a stand-by. It was also necessary to consider the ‘fuel cask’ of plutonium-238 for the RTG. The cask gave structural support and thermal insulation to the fuel capsule: in the case of the SNAP-27 unit for the ALSEP this comprised 8.4 pounds of plutonium. On the Moon, an astronaut would require to remove the 500°C fuel capsule from the cask on the exterior of the LM and insert it into the thermocouple assembly. When simulations revealed flaws in this procedure, the design had to be modified, and after several launch failures unrelated to the Apollo program the cask had also to be ‘hardened’ to ensure that it would not spill its contents. The Manned Spacecraft Center established the Science and Applications Directorate in December, which took over the activities of the Experiments Program Office and, as Newell had long urged, put science on a par with engineering and operations. Wilmot N. Hess, formerly of the Goddard Space Flight Center, was appointed as Director of the Science and Applications Directorate, with Piland as his deputy.

On 4 January 1967 Christopher C. Kraft, Director of Flight Operations at the Manned Spacecraft Center, said that if a lunar landing was to involve two surface excursions, the first outing should facilitate lunar environment familiarisation, an inspection of the vehicle, photographic documentation and contingency sampling. The ALSEP should be deployed on the second outing, and be followed by a more systematic geological survey. Conversely, if only one excursion was planned, that mission should not be provided with an ALSEP since its deployment would use a disproportionate amount of the time. This rationale applied particularly to the first landing, when the mass saved by deleting the instruments would undoubtedly be able to be put to good use. It was also decided that the astronauts should be provided with a rough time line but be allowed to make real-time decisions; the surface operations must not be micro-managed by Mission Control, at least not on the first mission, when there would be so many unknowns and the people on the spot would be best positioned to make decisions. On 16 March NASA announced that 110 scientists, including 27 working in laboratories outside the USA, had been selected to receive lunar samples. In June, Apollo Program Director Samuel C. Phillips formed an ad hoc team to review the status of the magnetometer. It was concluded that while the technical problems were certain to be resolved, the instrument was unlikely to be ready for the first landing, which at that time was thought might occur in the latter part of 1968. Unfortunately, neither would the simpler magnetometer be ready for that date, so work on this was terminated. Leonard Reiffel, on Phillips’s science staff, recommended on 20 June that in view of the uncertainties concerning an astronaut’s ability to work in one-sixth gravity, “an uncrowded time line’’ would be “more contributory to the advance of science than attempting to do so much that we do none of it well’’.

By mid-September 1967, on the basis of the LM spending 22.5 hours on the lunar surface, the planners recommended that two excursions should be defined, but the second, to follow a sleep period, should not be listed as a primary objective. The decision on whether to conduct the second excursion – on which the ALSEP would be deployed – should be made on the basis of the astronauts’ performance during the first outing. However, one year later, on 6 September 1968, with the LM significantly overweight and the development of the RTG behind schedule, Robert R. Gilruth, Director of the Manned Spacecraft Center, recommended that the first landing should make a single excursion of 2.5 hours; the ALSEP should not be carried (as it could not function without the RTG); the high-gain antenna for the television should not be carried (instead, the 210-foot-diameter antenna at Goldstone in California could receive a transmission from a smaller antenna on the LM); and the geological activities be restricted to the ‘minimum lunar sample’. As Gilruth put it, “I’m sure all will agree that if we successfully land on the Moon, transmit television directly from the surface, and return with lunar samples and detailed photographic coverage, our achievement will have been tremendous by both scientific and technological standards.’’ However, Hess argued for a compromise in which, in view of the development problems of the ALSEP, a smaller package should be assigned to this

mission using instruments that would be easier to deploy, with the duration of the outing being open ended. On 9 October the Manned Space Flight Management Council, chaired by Mueller, agreed to the development of three lightweight experiments for the first landing mission – a solar-powered passive seismometer, an unpowered laser reflector, and a solar wind composition experiment that would be deployed and later retrieved for return to Earth. It was decided to carry the erectable antenna for the television transmission in case the time of the moonwalk did not coincide with a line-of-sight to Goldstone. The mass saved by not carrying the ALSEP would allow more fuel to be carried, and thereby increase the time available for the hovering phase of the descent. In effect, the first landing was to be an ‘operational pathfinder’ for its successors. On 5 November Bendix was told to make the three-instrument Early Apollo Surface Experiments Package (EASEP), which was to be shipped by mid-May 1969. On 6 December Phillips said that if the special tools under development for the geological investigation were ready, and if the astronauts had sufficient time to train in their use, they would be carried. One such item was a camera designed by Thomas Gold, an astronomer at Cornell University. In the early 1960s he had argued, on the basis of radar reflections, that the lunar surface was a thick blanket of extremely fine dust into which a spacecraft would sink without trace, and he maintained this position even after automated landers settled on firm ground. His camera was designed to take stereoscopic close-up pictures of the lunar dust.

FIRST MAN OUT

At the press conference in Houston on 10 January 1969 that introduced the crew of Apollo 11, a reporter enquired about which of them would be first to set foot on the Moon. Armstrong turned to Deke Slayton, Director of Flight Crew Operations, for guidance. Slayton said the matter had not yet been decided, but would be resolved by the training exercises. This ambiguity provoked much speculation in the media. The Gemini precedent was that a commander remained in the spacecraft while his copilot undertook extravehicular activity. In March, after the success of Apollo 9 increased the likelihood of Apollo 11 being assigned the first lunar landing, Kraft and George M. Low, Manager of the Apollo Spacecraft Program Office in Houston, had an informal discussion and both felt that since the first man to set foot on the Moon should be a Lindbergh-like figure, Armstrong would be preferable to Aldrin. On hearing a rumour that Armstrong had been chosen to egress first because (despite his being a former naval aviator) he was ‘‘a civilian’’, Aldrin discussed the issue with Armstrong, who said simply that since it was not their decision to make they must wait and see. Several days later, Aldrin went to Low and urged that a decision be made in order to facilitate training. This was a reasonable request, because one of Aldrin’s assignments in planning the mission was to refine procedural issues. Low and Kraft then met with Gilruth and Slayton, and they formally decided that the first man to exit the LM would be Armstrong, if only for the fact that the hatch was hinged to open towards the man on the right, meaning that the man on the left, the

Portable life-support system 17

commander, must exit first. When Slayton called the astronauts into his office, he cited the hinge on the hatch as the reason for Armstrong being first out and last in.1 On Monday, 14 April, Low announced to the press that if all went well, Armstrong would be the first man to set foot on the lunar surface.

Apollo spacecraft CSM-107 was built by North American Rockwell at its plant at Downey, California. The conical command module was 11 feet 5 inches high, 12 feet 10 inches in diameter, and provided a habitable volume of 210 cubic feet. The cylindrical service module was 12 feet 10 inches in diameter and 24 feet 7 inches tall. Radial beams divided it into a central tunnel, which contained tanks of helium pressurant, and six outer compartments, four of which held propellant tanks, one contained the fuel cell system and the sixth was unused.9 The systems tests on the individual modules were completed on 12 October 1968, and the integrated tests on 6 December. The modules were flown to the Cape on 23 January 1969 by a ‘Super Guppy’ aircraft of Aerospace Lines. They were mated on 29 January, passed their combined systems testing on 17 February and altitude chamber tests on 24 March. At the Grumman Aircraft Engineering plant at Bethpage on Long Island, LM-5 completed its integrated test on 21 October 1968, and its factory acceptance test on 13 December. The ascent stage arrived at the Cape on 8 January 1969 and the descent stage on 12 January. After acceptance checks, the stages were mated on 14 February, passed their integrated systems tests on 17 February, and altitude chamber tests on 25 March. Overall, the vehicle stood 22 feet 11 inches tall. The descent stage was 10 feet 7 inches high and had a diagonal span of 31 feet across its foot pads. Two layers of parallel beams in a cruciform shape gave it a central cubic compartment (housing the descent engine), four cubic side compartments (each housing a propellant tank) and four triangular side compartments (carrying apparatus the astronauts would require during their moonwalk). The ascent stage comprised a pressurised crew compartment and midsection with a total volume of 235 cubic feet, and an unpressurised aft equipment bay.

The 138-foot-long, 33-foot-diameter S-IC first stage of the sixth launch vehicle in the Saturn V series was fabricated by Boeing at the Michoud Assembly Facility in Louisiana, and moved in a horizontal configuration by barge up the Intracoastal Waterway to the Mississippi Test Facility, arriving on 6 August 1968. It was then shipped around the southern tip of Florida, to the Kennedy Space Center. On arrival on 20 February 1969 the 24-wheeled trailer bearing the stage was offloaded by a

The fuel cell system had three fuel cells, two tanks of cryogenic oxygen and two tanks of cryogenic hydrogen, and provided 28 volts.

prime mover and driven into the ‘low bay’ annex of the Vehicle Assembly Building. The S-II second stage had the same diameter as the S-IC, but was only 81 feet 6 inches in length. After assembly at the North American Rockwell plant at Seal Beach in California, it was shipped via the Panama Canal to the Mississippi Test Facility, where it was tested on 3 October 1968. On arriving at the Cape on 6 February 1969, the S-II, complete with its 18-foot-tall aft interstage ‘skirt’, was driven on its 12­wheeled trailer to the low bay. After tests at the Douglas Aircraft Corporation facility in Sacramento, California, the S-IVB third stage was flown to the Cape by ‘Super Guppy’ on 19 January 1969. In all, some 12,000 companies across America participated in the production of the launch vehicle.

The principal structure of the Vehicle Assembly Building was 718 feet long, 517 feet wide and 525 feet tall. Its internal volume of almost 130 million cubic feet required a 10,000-ton air-conditioning system to prevent a ‘weather system’ with its own rainfall developing. The cavernous interior provided four ‘high bays’ for simultaneous assembly of Saturn V vehicles. Each pair of bays shared a bridge crane located 462 feet above the floor. The operator was in walkie-talkie contact with his colleagues at the work sites, and used a computer to move loads of up to 250 tons with a tolerance of 1/228th of an inch. Mobile Launch Platform 1 was a two-level steel structure 160 feet long, 135 feet wide and 25 feet high. At one end was the Launch Umbilical Tower, which rose 398 feet above the deck, and offset towards the other end of the platform was a 45-foot-square hole to allow launch vehicle exhaust to pass through. On 21 February the S-IC was hoisted, turned to vertical, and clamped to the supporting arms, one on each side of the hole. The S-II was added on 4 March. The next day the 260-inch-diameter S-IVB, now with its flared aft skirt fitted, was added, and the Instrument Unit containing the guidance system for the launch vehicle (which had arrived on 27 February) was placed on top. The 28-foot – long truncated-cone to house the LM and support the 154-inch-diameter CSM was fabricated at the North American Rockwell plant in Tulsa, Oklahoma, and delivered on 10 January. The integrated CSM, LM, adapter and launch escape system tower was referred to as the ‘spacecraft’ because it was the payload of the three-stage launch vehicle. Its addition on 14 April completed the ‘stack’. From the aperture of the F-1 engines of the first stage to the tip of the escape tower, the ‘space vehicle’, as the integrated launch vehicle and spacecraft was known, stood 363 feet tall. Nine hydraulically operated arms on the umbilical tower provided access to key sections of the vehicle.[17] The combined systems test of LM-5 was finished on 18 April. The integrated systems test of CSM-107 was completed on 22 April, and the spacecraft was electrically mated with the launch vehicle on 5 May. The overall test of the space vehicle was accomplished on 14 May.

The 6-million-pound transporter for the mobile launch system was 131 feet long,

VHF ANTENNA(2)

TRANSFcR TUNNEL AND OVERHEAD HATCH

EVA ANTENNA

AFT EQUIPMENT BAY

REPLACEABLE ELECTRONIC ASSEMBLY

FUEL TANK (REACTION CONTROL)

REACTION CONTROL

INGRESS/EGRESS HATCH

CREW COMPARTMENT

LAND NG

PAD (4)

LUNAR SURFACE SENSING PROBE

A cutaway diagram of the two LM stages.

Launch Escape System (LES)

ty, ‘ у Command module (CM)

Service module (SM)

Spacecraft/LM adapter (SLA)

Lunar Module (LM)

Instrument Unit (IU)

S-IVB

From the point of view of the Saturn V launch vehicle, the ‘spacecraft’ comprises the Launch Escape System, the CSM, and the LM contained within the adapter.

The space vehicle for Apollo 11 is ‘stacked’ in the Vehicle Assembly Building (clockwise from top left): a crane hoists the S-IC on 21 February; the S-II is added on 4 March; the S-IVB is added on 5 March; and the spacecraft is added on 14 April 1969.

114 feet wide, and travelled on four independent double-tracked crawlers, each ‘shoe’ of which weighed about 1 ton. The access road was comparable in width to an 8-lane highway. It comprised three layers, averaging a total depth of 7 feet. The base was a 2-foot-6-inch-thick layer of hydraulic fill. Next was a 3-foot-thick layer of crushed rock. This was sealed by asphalt. On top was an 8-inch layer of river rock to reduce friction during steering. The vehicle was operated jointly by drivers in cabs located on opposite diagonals, who communicated by intercom. On 20 May the Apollo 11 space vehicle was driven to Pad A, the southernmost of the two launch sites of Launch Complex 39. Because the concrete pad was built above ground level to accommodate a 43-foot-tall flame deflector in the flame trench, the transporter had to climb a 5 per cent gradient while tilting the platform such that the tip of the launch escape system tower did not diverge more than 1 foot from the vertical alignment. Once in position, hydraulic jacks lowered the platform to emplace it on six 22-foot-high steel pedestals on the pad. In all, the ‘roll out’ lasted 6 hours. In its final orientation, the umbilical tower stood towards the north, with the axis of the central trench aligned north and south. After the transporter had withdrawn, the flame deflector was rolled in beneath the hole in the platform. On 22 May, the transporter collected the Mobile Service Structure from its parking place alongside the access road, and delivered it to the pad. The flight readiness test was completed on 6 June. The countdown demonstration test started on 27 June; the ‘wet’ phase was completed on 2 July, and the ‘dry’ phase on 3 July. As Kurt H. Debus, Director of the Kennedy Space Center, once said in jest, ‘‘When the weight of the paperwork equals the weight of the stack, it is time to launch!’’

After the P22 landmark tracking, Collins had initiated a manoeuvre to orient the docked vehicles to enable Eagle to calibrate its abort guidance system (AGS). As he waited for this to finish, he noted that there was an advantage to being behind the Moon, as they then were, “It’s nice and quiet over here, isn’t it?’’

“You bet,’’ agreed Aldrin.

On finishing the manoeuvre, Collins nulled out the rates and then went ‘free’ while Eagle performed the calibration. After five minutes Collins asked, ‘‘How’s the Czar over there? He’s so quiet.’’

‘‘I’m punching buttons,’’ replied Armstrong, referring to the DSKY activity.

A few minutes later, Collins, having been thinking ahead, urged, ‘‘You cats take it easy on the lunar surface. If I hear you huffing and puffing, I’m going to start bitching at you.’’

“Okay, Mike,’’ Aldrin promised.

During the calibration, the only tasks that could be performed were those that would not induce vibrations. One permissible operation was to open the helium valves to pressurise the DPS propellant tanks. Once the calibration was finished, Collins called, “I’m going to manoeuvre to the undocking attitude.’’ He aligned the docked vehicles ‘vertically’, with the CSM beneath. “How about 100 hours and 12 minutes as an undocking time? Does that suit your fancy?’’

“That’ll be fine,’’ agreed Armstrong.

‘‘Are you guys all set?’’ Collins asked, as the clock ticked down.

‘‘We’re all set when you are, Mike,’’ Armstrong confirmed.

‘‘15 seconds,’’ called Collins. He released the capture latches. If these were to fail to release, the design allowed for a suited crewman to manually release them, either by Collins pulling a handle or by a LM crewman pushing a button on the tip of the probe; in either case, the cabin would require to be depressurised and the appropriate hatch opened to gain access to the mechanism. The latches, however, did release. As the residual air in the tunnel escaped, it made the vehicles slowly drift apart.

Since it was desired that the LM remain in the orbit resulting from the LOI-2 manoeuvre, the parameters of which had been precisely defined by Manned Space Flight Network tracking, the same state vector had been loaded into both vehicles and as soon as Eagle was free Armstrong cancelled the 0.4-foot-per-second rate of separation that the PGNS indicated had resulted from the undocking.[23]

‘‘I’ve killed my rates, Mike,’’ Armstrong announced, ‘‘so you drift on out to the distance you like and then stop.’’

When Collins was about 65 feet away, he halted to station-keep.

Meanwhile, in the Aldrin home, son Andrew wondered aloud why NASA had not installed a communications satellite to relay while the spacecraft was behind the Moon.[24] In the Collins home, Joe and Mary Engle were looking after the children. Pat Collins, flight plan on her lap, was eager for AOS to find out if the undocking had occurred. Jan Armstrong was also at home with her flight plan, thinking the same thoughts.

‘‘Eagle. Houston. We’re standing by,’’ called Duke as the vehicles appeared on revolution 13.

‘‘The Eagle has wings,’’ replied Armstrong.

Collins had installed his 16-millimetre Maurer in window 4 to document this part of the mission. On the flight plan, the television camera was to have been set up

alongside it to provide ‘live’ television, but about 57 hours into the translunar coast Houston had cancelled this telecast owing to the lack of an available channel on a geostationary satellite to relay the transmission from the Madrid receiving station to Houston for conversion. In any case, as Collins had said shortly prior to LOS, he was too busy to set up the television system. The loss of ‘live’ views of Eagle in flight was a disappointment to the national television networks, which had hoped to use it to introduce their uninterrupted coverage of the next phase of the mission.

Several minutes into the near-side pass, Armstrong yawed Eagle around and pitched it up in order to place it ‘side on’ to Columbia, and then slowly yawed it through 360 degrees to enable Collins to visually confirm that the legs had fully deployed and the probes were in position. An unusual sound late in the translunar coast had prompted Armstrong to speculate that the hinged panel on the right side of the vehicle had prematurely deployed, but Collins confirmed that this was in its stowed configuration. ‘‘You’ve got a fine-looking flying machine,’’ he assured.

‘‘See you later,’’ promised Armstrong, as the separation manoeuvre loomed.

‘‘You guys take care,’’ said Collins. With his spacecraft oriented apex-up, he fired his forward-facing RCS for 8 seconds to impart a downward radial thrust in order to withdraw at 2.5 feet per second, during which time the rendezvous radar mounted on Eagle’s ‘forehead’ tracked Columbia as a test of the radar’s ability to lock onto the transponder on the other vehicle, and Columbia tested its VHF ranging apparatus; these tests being designed to verify the rendezvous systems prior to Eagle entering the descent orbit. The separation burn occurred about 10 degrees east of the landing site, and placed Columbia into an equi-period orbit with its perilune 90 degrees later, and some 5 nautical miles lower.

Meanwhile, at home

Astronauts cycled back and forth between the Armstrong and Aldrin homes, as indeed did their wives, although rarely together because their efforts were divided between the families – it was a routine that Jan and Joan understood, as they had done the same thing themselves, and there was no need to play host because it was a self-organising process.

The flight dynamics team felt sufficiently confident to further reduce the size of the target ellipse and reject the requirement that the landing site be free of terrain relief, to permit the next mission to tackle a more confined site in rougher terrain. In 1962 Gene Shoemaker and R. J. Hackman had issued a stratigraphic map of part of the Imbrium Basin’s rim. In extending this map, R. E. Eggleton classified the peripheral hummocky terrain as ejecta from the Imbrium impact, and called it the Fra Mauro Formation. Although one geological unit, this terrain was distributed in isolated patches around the periphery of the basin. In terms of total area, it was the largest distinct stratigraphic unit on the near side. Contemporary understanding of lunar history was based on how the ejecta from the Imbrium impact had splattered across thousands of miles. Dating this impact was the single most important item on the lunar science agenda, as it would ‘lock in’ many other structures. It was not just a matter of learning about the Moon. The lunar basins indicated that the early Solar System was an extremely violent place. If the Moon had suffered such an intense bombardment so, too, must Earth. Studying the Moon would provide insight into the early history of our own planet. The terrestrial record of this age is missing, in part because of erosion but mainly because the crust is recycled by plate tectonics. The Moon, however, is so endogenically inert that its face has remained essentially unchanged for billions of years. The task was to find a crater in the hummocky Fra Mauro Formation which had a rocky rim, offered a safe line of approach from the east, and was within a mile of a landing site. A 1,200-foot-diameter pit situated 22 nautical miles north of the large crater Fra Mauro, south of the Imbrium Basin, was chosen. As a result of its shape, the ‘drill hole’ crater to be sampled was named Cone. The best landing site was on the undulatory plain 1,000 yards further west, but the target was set twice as far out in order to avoid the fringe of Cone’s ejecta. So great were the results to be gained from this site that after Apollo 13 had to abort and make an emergency return to Earth, Apollo 14 was reassigned this site and the target moved to the optimal landing place.

On 5 February 1971 Al Shepard and Ed Mitchell landed their LM, ‘Antares’. Following the pattern, they deployed their ALSEP on the first day and made the traverse on the second. Since the rocks were consolidations of shattered precursors (i. e. breccias) the analysis was rather more complicated than for previous missions. The primary objective was to date when the fragments had been bound together, in order to date the impact that applied the shock. This was achieved by exploiting the fact that the isotopic ‘clocks’ used to measure formation date are ‘reset’ when a rock is melted. This was not an issue for basalts from the dark plains, but the study of a breccia involved dating its individual clasts. The samples tended to cluster in two age ranges, one spanning the interval 3.96 to 3.87 billion years and the other spanning the interval 3.85 to 3.82 billion years. It was therefore inferred that the breccias

formed around 3.84 billion years ago as ejecta splashed from the Imbrium impact. The older dates provided the formation ages of the rocks shattered by that impact. It had been hoped that samples taken from right on Cone’s rim would characterise the basement on which the Fra Mauro Formation resided, which was expected (by some) to be volcanic. At first, several intriguing samples did look as if they might represent such volcanism, but they proved to be the first instances of another type of breccia. In fact, there proved to be many forms of breccia. The terms ‘fragmental breccia’ was coined for clasts of shattered rock bound up in a matrix of pulverised rock. As further samples were studied, it was found that fragments of individual minerals could become bound into breccias, showing that not all clasts were lithic. Also, since breccias themselves could be caught in impacts, there were ‘breccias of breccias’ in which the clasts of one breccia were fragments of earlier breccias, and the term ‘one-rock’ and ‘two-rock’ were coined to reflect this history. The samples initially thought to be volcanic were a type of breccia in which clasts were bound in impact-melt.4 Despite the violence of the shock-melting, the breccias contained very fragile crystals that could only have been formed by diffusion as mineral-rich vapour escaped from the ejecta. This crystallisation process was very similar to sulphur encrustation of volcanic vents on Earth, but in this case the gas was released by the ejecta itself rather than from the ground on which the ejecta sat, indicating that the rubble was hot when it was deposited and then fused as it congealed. Intriguingly, the impact-melt breccias proved to be KREEPy. Analysis revealed that they were originally a gabbro (i. e. a basalt that solidified deep underground rather than on the surface) that derived from the magma ocean. In the process of crystallisation, an element is accepted or rejected according to whether it fits the crystalline structure; elements that do not fit are known as ‘incompatibles’. As trace elements tend not to participate in mineralisation, they remain in the melt as the ‘compatible’ elements are extracted, with the result that their concentration progressively increases. The radioactives at depth helped to maintain this reservoir molten, and were locked in when it finally solidified. The impact that made the Imbrium Basin had penetrated sufficiently deep to excavate and scatter some of this material across the surface; mystery solved.

THE END OF THE BEGINNING

Apollo 14 drew to a conclusion the initial phase of the exploration of the Moon in which astronauts traversed on foot. Even before Apollo 11, NASA had ordered the design of a battery powered Lunar Roving Vehicle to enable the so-called ‘J’-class missions to range far and wide across their sites, carry a variety of tools, and return a large amount of material. . . but the stories of these missions are for another book.

Impact melt resembles basalt to the extent that it is a solidified rock melt, but endogenic basalt is homogeneous.

On 14 April 1969 Neil Armstrong, Buzz Aldrin and Mike Collins donned their training suits to have their Apollo 11 portrait taken in front of a 5-foot-diameter picture of the Moon.

Frames from the 16-millimetre camera showing Neil Armstrong collecting the contingency sample alongside Eagle, setting up the television camera, and, with Buzz Aldrin, erecting the Stars and Stripes.

Buzz Aldrin stands alongside the SWC. The rim of the crater that Eagle passed over immediately prior to landing forms the horizon, marred by the glare of the Sun.

Part of a panoramic sequence taken by Buzz Aldrin looking north across Eagle’s shadow, showing the television tripod, the Stars and Stripes and Neil Armstrong working at the MESA.

Having left the ALSCC where he took the previous picture, Neil Armstrong moved further out to take a panoramic sequence, catching Buzz Aldrin placing the PSE on the ground. The LRRR is still in the SEQ bay. Notice the ‘washed out’ landscape down-Sun, due to backscattered sunlight and the fact that shadows are masked by the objects that cast them.

[1] Madalyn Murray O’Hair, a militant atheist, described by Life magazine in 1964 as “the most hated woman in America’’, sued the federal government over Apollo 8’s reading from Genesis, arguing that this violated the separation of state and church. This was rejected by the Supreme Court.

[2] In 1967 North American Aviation merged with the Rockwell Standard Corporation, as North American Rockwell; in 1973 this became Rockwell International.

[3] The Stars and Stripes shoulder patch was introduced by Jim McDivitt and Ed White after being prohibited from naming their Gemini 4 spacecraft ‘American Eagle’. In addition to retaining the flag, for their Gemini 5 flight Gordon Cooper and Pete Conrad introduced a mission patch. Both became standard adornments.

[4] Asa treat, in his personal preference kit Armstrong had an opal that Wendt had supplied, which, upon its return to Earth, Wendt intended to give to his wife Herma.

[5] Wendt kept the trout in his deep freeze until having it remounted in a more conventional way.

[6] Britain’s ambassador to Washington, John Freeman, having attended the launch of Apollo 10, declined his invitation to Apollo 11 on the basis that – as an embassy spokesman put it – ‘‘when you’ve seen one Apollo launch, you’ve seen them all’’.

[7] The Saturn V was so much more powerful than its predecessors that the sound of the first launch on 9 November 1967 took everyone by surprise. ft not only rattled the tin roof of the VfP bleacher but also threatened to collapse the booth from which Walter Cronkite was providing his television commentary.

[8] NASA preferred to use nautical rather than statute miles for space missions. One nautical mile is 2,000 yards, or 6,000 feet; whereas a statute mile is only 1,760 yards or 5,280 feet.

[9] Three of these names were coined by Gus Grissom to celebrate his Apollo 1 crew (‘Navi’ was his middle name, ‘Ivan’, spelt in reverse; ‘Dnoces’ was the reverse spelling of ‘second’, as in Edward H. White II; and ‘Regor’ was the reverse spelling of ‘Roger’, as in Roger B. Chaffee) and, as far as the International Astronomical Union was concerned, they were unofficial.

[10] Of the ‘Original Seven’ astronauts, Wally Schirra, Gus Grissom and Gordon Cooper were on the active list; Deke Slayton and Al Shepard had been grounded for medical reasons; Scott Carpenter had returned to the Navy; and John Glenn, who had been grounded on the basis that as a national icon he was too valuable to risk on a second mission, had left to pursue a political career.

[11] Being detachable, the magazine of a Hasselblad is traditionally referred to simply as a ‘back’.

[12] The engine did not ‘burn’ its propellant; instead a silver catalyst in the chamber converted the H2O2 to superheated steam and oxygen, and the gas passed through the nozzle to produce thrust.

[13] The Lunar Landing Research Facility at the Langley Research Center became operational on 30 June 1965. It was a 260-foot-tall 400-foot-long frame structure with a system of travelling pulleys to suspend a vehicle in such a manner as to balance five-sixths of its weight. It provided a ‘flying volume’ 180 feet in height and 360 feet in length, with a lateral range of 42 feet. Its main role was to test instruments and software to be used by the LM during the final 150 feet of a lunar descent, but astronauts used it to familiarise themselves with flying in one-sixth gravity prior to advancing to the LLTV.

[14] Based on an account in First on the Moon: A Voyage with Neil Armstrong, Michael Collins and Edwin E. Aldrin Jr, by Gene Farmer and Dora Jane Hamblin. Michael Joseph, pp. 216­218, 1970.

[15] In his debriefing after Apollo 11, Armstrong confirmed the fidelity of the LLTV, and thereafter each mission commander trained with it.

[16] The hypergolic propellants were nitrogen tetroxide oxidiser and a fuel comprising a 50:50 mix of hydrazine with monomethyl hydrazine. The RCS of the CSM required 300 pounds, the SPS of the CSM required 41,000 pounds, and the LM’s propulsion systems required a total of 23,245 pounds.

[17] The swing arm numbers and their interface points are: 1, S-IC intertank; 2, S-IC forward; 3, S-II aft; 4, S-II intermediate; 5, S-II forward; 6, S-IVB aft; 7, S-IVB/IU forward; 8, SM; 9,

crew access.

[18] The eagle that attracted Collins’s interest appeared on p. 236 of the book, Water, Prey, and Game Birds of North America, published by the National Geographic Society in 1965. In fact, the plate in the book was a mirror image of the original painting by Walter Alios Weber, which was published in the July 1950 issue of National Geographic Magazine. The eagle on the mission patch matches the orientation in the original.

[19] Telemetry showed the RCS propellant supply to be about 20 pounds below nominal following the transposition manoeuvre.

[20] In some ways, the most unfortunate person involved in the mission was the man who opened the hatch immediately following splashdown!

[21] Prior to the dawning of the space age, astronomers had defined lunar longitudes in terms of their view of the Moon in the terrestrial sky, with the leading limb being east. However, in 1961 the International Astronomical Union had redefined the system to place east in the direction of sunrise as seen from the lunar surface, which reversed the old scheme.

[22] At the post-flight party, the flight controllers voted Bill Tindall an honorary flight director, with the team colour grey.

[23] As was realised later, however, although the impulse from the tunnel venting was cancelled, this manoeuvre, and others made while ‘displaying’ Eagle to Collins, imparted slight residuals which, when propagated forward in time through the DOI manoeuvre, nudged Eagle’s trajectory slightly ‘off at the PDI point.

[24] Some at NASA would later suggest doing precisely this for later missions.

[25] The ground level of Mission Control held the Real-Time Computer Complex, and each of the two upper levels held a Mission Operations Control Room. Apollo 11 was managed from the top level.

[26] What no one realised was that the program driving the antenna was flawed, with the result that at certain times what was expected to be a clear line of sight to Earth was blocked by the structure of the vehicle.

[27] For the LM, yaw was a rotation around the thrust axis.

[28] There was a spare Maurer body, and Aldrin had tested both cameras during his inspection earlier in the mission; the spare was not needed (and was jettisoned with the trash after the moonwalk).

[29] This was long before the advent of computer-generated imagery, so the animations now appear quaint!

[30] Post-mission analysis established that several interrelated factors contributed to the position-velocity error at PDI – including uncoupled attitude manoeuvres such as station­keeping, hot-fire thruster testing, and venting of the sublimator cooling system – but most of these perturbations were more or less self-cancelling. The principal error was the propagation forward of the impulse imparted at undocking due to the incomplete venting of the tunnel; this was not a mistake by Collins, it was an oversight in planning. Due to the ‘vertical’ attitude of the stack at undocking, the perturbation was to the radial component of Eagle’s velocity.

[31] The down-Sun line was called the ‘zero phase’. With the Sun low in the east, the shadows of rocks and craters were hidden when looking west, and coherent backscatter from cleavage planes in the fractured crystalline rocks produced a very strong solar reflection that tended to ‘wash out’ the scene.

[32] At the time of Apollo 11, the law suit brought by Madalyn Murray O’Hair regarding the reading from Genesis by the Apollo 8 crew was still pending.

[33] Due to Armstrong’s manner of speech, he appears to have appended the ‘a’ to ‘for’, which came out as ‘for-a’, thereby giving the impression that he misspoke and uttered something meaningless!

[34] The time in Houston was 9.56 pm on Sunday, 20 July 1969.

[35] Vesicles were a characteristic of igneous rock in which the melt contained bubbles of gas that left spherical holes in the solidified rock. Since this occurs more readily in lava that has been extruded onto the surface or is at shallow depth, it supported the inference that the landing site was a basalt lava flow. Armstrong would expand on this observation later in the excursion.

[36] Phenocrysts were crystals embedded in the finely grained matrix of an igneous rock.

[37] These accounts are derived from interviews compiled by Glen E. Swanson in Before this Decade is Out… Personal Reflections on the Apollo Program, SP-4223, NASA, 1999.

[38] As indeed would happen at this point in the mission of Apollo 12.

[39] Engineers in Houston designed a ‘stand’ which, when deployed, would display the flags of the member states of the United Nations in the style of a tree.

[40] This picture of Aldrin became the iconic Apollo 11 ‘Man on the Moon’ image. It is on the front cover of this book.

[41] Although McCandless was told that a laser reflection had been detected while Eagle was still on the surface, and he relayed this news to Collins, this was not so.

[42] The seismometer included a detector to measure dust accumulation and radiation damage to the solar cells, and an isotope heater to keep the electronics warm during the long lunar night. Despite operating temperatures that exceeded the planned maximum by 30°C, the instrument functioned normally through the maximum heating around lunar noon. With the power output from the solar arrays in decline about 5 hours before local sunset (on 3 August 1969) transmission was halted by command from Earth. ft was turned on again on the next lunar day, but (on 27 August) near noon of this second lunar day the instrument ceased to accept commands and the experiment was terminated.

[43] The platform began to be unusable after 4 hours, and the computer failed just over 3 hours later. Both items had operated for considerably longer than had been predicted. The other systems were still functioning. The last contact with Eagle was at 137:55, when the battery output dipped below that required for the AGS to maintain the vehicle’s attitude within the antenna’s requirements for communication with Earth. Although Eagle was released in an almost circular orbit, perturbations by the mascons would soon have caused it to strike the surface, but it is not known when or where this occurred.

[44] On subsequent missions, crews would tease Duke about this misidentification.

[45] In fact, Armstrong was in error because Columbiad was the name of the giant cannon that fired Verne’s spaceship to the Moon; the ship did not have a name, always being referred to simply as ‘‘the projectile”.

[46] Note that there was a presumption that the astronauts would not get sea sick while wearing their suits, as the mask would have to have been removed in order to vomit, which would have violated the isolation.

[47] There are several Hasselblad pictures of Armstrong on the lunar surface, but he is in shadow and it was some time before his presence on these frames was noted.

[48] The aim point was at 0°42’50"N, 23°42’28"E.

[49] Actually, as Apollo 11 was heading home, NASA decided to withdraw one Saturn V from the lunar program in order to launch the Skylab space station, but this had not yet been announced.

[50] This is what Pete Conrad and Al Bean did after walking on the Moon on Apollo 12. Their CMP, Dick Gordon, remained in the lunar program in the hope of commanding Apollo 18, but this flight was cancelled.

[51] The name ‘armalcolite’ was derived from the first letters of the astronauts’ surnames. Some years later this mineral was found on Earth, too.

[52] These could be characterised in terms of their terrestrial equivalents as olivine basalt, pyroxene basalt, ilmenite basalt and feldspathic basalt.