Category Paving the Way for Apollo 11

BORING HOLES IN THE SKY

AS-205 lifted off from Pad 34 at 15:02:45 GMT on 11 October 1968 to fly the ‘C’ mission. Flown by Wally Schirra, Donn Eisele and Walt Cunningham, Apollo 7 was

to be open-ended up to 11 days and its purpose was to assess the performance of the Block II spacecraft.

The ascent phase was nominal and the S-IVB achieved a 123 x 152-nautical mile orbit. Prior to separating from the spent stage, the crew temporarily took command of the Instrument Unit and manually manoeuvred the combined vehicle in pitch, roll, and yaw, then they returned control to the launch vehicle. By the time the spacecraft separated at 002:55:02.40, venting of S-IVB propellants had raised the orbit to 123 x 170 nautical miles. The spacecraft moved clear, flipped and moved back in as if to retrieve the LM (which was absent). Since one of the four panels of the SLA had not fully deployed, it was decided that in future the panels would be jettisoned. One of the primary objectives was to demonstrate Apollo’s rendezvous capability using the spent stage as the target. At Schirra’s insistence, one man was awake at all times to monitor the spacecraft’s systems, even though the ongoing work made sleeping difficult. The rendezvous rehearsal was successfully achieved on the second day.

Although this was the first US spacecraft to have sufficient habitable volume for a man to leave his couch and move around, the crew suffered no disorientation in the weightless state, despite efforts to induce motion sickness. However, all three men developed head colds early on, making them grumpy, and in-flight TV, which was a secondary objective, provided a focus for their frustration. When the monochrome camera was finally switched on, however, it delivered excellent results and the crew played up to their audience. But it was a long and tedious flight of monitoring the systems to evaluate their performance, always prepared to intervene in the event of a problem. In fact, it was an exercise in would later be derided as “boring holes in the sky’’.

At 11:11:48 GMT on 22 October the command module splashed in the Atlantic 1.9 nautical miles from the target point. It initially assumed an apex-down attitude, but was soon turned apex-up by the inflatable bags on its nose. The astronauts were retrieved by helicopter and arrived on USS Essex an hour later.

The Apollo 7 mission was successful in every respect, with the service propulsion system firing perfectly eight times. Indeed, afterwards Schirra described the flight as a “101 per cent success’’. In combination with previous missions and ground tests, it certified the CSM for use in Earth orbit and for tests in the cislunar and lunar orbital environments.

MEN ORBIT THE MOON!

On 7 November 1968 George Mueller declared that AS-503 was fit for a mission to the Moon. On 11 November Sam Phillips recommended to the Manned Space Flight Management Council that Apollo 8 enter lunar orbit. Later that day, Mueller told Thomas Paine that he had discussed the mission with the Science and Technology Advisory Committee and with the President’s Science Advisory Committee, both of which had endorsed the proposal, and he recommended that it should be undertaken. After speaking to Frank Borman by telephone, who confirmed his willingness to fly the mission, Paine gave the formal go ahead and told Phillips to make the necessary arrangements. The next day, NASA announced that Apollo 8 would be launched on 21 December and attempt a lunar orbital mission. Earlier in the year, Michael Collins had withdrawn from the crew to undergo a surgical procedure, and had been replaced by his backup, James Lovell.

Tom Stafford, John Young and Gene Cernan were announced on 13 November as the prime crew of Apollo 10, backed up by Gordon Cooper, Donn Eisele and Edgar Mitchell. This established the precedent for a crew backing up one mission, skipping two, and becoming the prime crew of the mission after that. It had yet to be decided, however, whether Apollo 10 would fly the ‘F’ or the ‘G’ mission.[51]

On 9 October 1968 AS-503, complete with CSM-103 and LTA-B, was rolled out to Pad 39A. The countdown demonstration test was completed on 11 December, and the actual countdown began at 00:00 GMT on 16 December. The launch window ran from 20 to 27 December, and it had been decided to try for 21 December to enable the astronauts to inspect the ALS-1 landing site in eastern Mare Tranquillitatis soon after local sunrise.

Frank Borman, James Lovell and Bill Anders entered the spacecraft with a little under 3 hours on the clock. There were no unplanned holds, and Apollo 8 lifted off at 12:51:00 GMT on 21 December for the ‘C-prime’ mission.

The ascent was nominal and the deviations from the trajectory when the S-IVB cut off at T+ 684.98 seconds were + 1.44 ft/sec in velocity and -0.01 nautical mile in altitude, which was almost perfect. At 002:27:22, after the S-IVB and spacecraft had been thoroughly checked, Collins, serving as the CapCom in Mission Control, made the momentous call, ‘‘Apollo 8, you are ‘Go’ for TLI.’’

The 317.7-second translunar injection was started at 002:50:37.8 and produced a velocity of 35,505.4 ft/sec. The spacecraft separated 30 minutes later and the four SLA panels were jettisoned. After turning around, the spacecraft’s ability at station­keeping with the spent stage was assessed. A 1.1-ft/sec manoeuvre was performed at 003:40:01 using the reaction control system of the service module to move clear of the stage, and a 7.7-ft/sec manoeuvre at 004:45:01 increased the separation rate.

At 004:55:56.0 the S-IVB opened its hydrogen vent valve and at 005:07:55.8 it passed oxygen through the engine. At 005:25:55.8 the auxiliary propulsion system was ignited and burned to depletion. The accumulated velocity increment placed the stage on course to fly by the trailing limb of the Moon at an altitude of 681 nautical miles and pass into solar orbit. The spacecraft’s service propulsion system executed a 2.4-second, 20.4-ft/sec midcourse manoeuvre at 010:59:59.2. A 24.8-ft/sec change had been planned, but the engine delivered less thrust than expected and a correction was made at 060:59:55.9 to refine the trajectory. These burns served to calibrate the service propulsion system in advance of calculating the orbit insertion manoeuvre.

In contrast to Apollo 7, this time all three crewmen experienced nausea as a result of rapid body movement, with the symptoms lasting up to 24 hours. The first of six TV transmissions started at 031:10:36 and ran for 23 minutes 37 seconds. The wide – angle lens gave an excellent view of the inside of the spacecraft, where Lovell was preparing a meal, but the telephoto lens passed too much light and pictures of Earth were poor. After a procedure was devised to tape a filter of the still camera onto the TV camera, it produced improved pictures of Earth during a transmission starting at 055:02:45. At 055:38:40 the astronauts were alerted that they had become the first people to enter a region where the gravitational attraction of another body exceeded that of Earth. The spacecraft had been slowing as it climbed up from Earth, but now it began to accelerate as it was drawn in by the Moon. However, they were not yet committed. If a reason developed not to brake into lunar orbit, then Apollo 8 would simply continue on its ‘free return’ trajectory around the back of the Moon and be ‘slingshot’ back to Earth. Although everything was going well, the translunar coast was frustrating in the sense that at no time were the crew able to see their objective owing to the spacecraft’s trajectory in relation to the positions of the Moon and the Sun.

The lunar orbit insertion manoeuvre began at 069:08:20.4 at an altitude of 75.6 nautical miles above the far-side of the Moon, and the 246.9-second burn produced an orbit ranging between 60.0 and 168.5 nautical miles with its high point above the near-side. After the post-burn checklist had been attended to, and while still passing over the far-side, the astronauts had their first opportunity to inspect the surface of the Moon up close. At 071:40:52 they gave a 12-minute TV transmission showing the passing terrain. In contrast to geologists, the astronauts described the surface in terms of ‘‘a battlefield’’, ‘‘a sandbox torn up by children’’, ‘‘a volleyball game played on a dirty beach’’, ‘‘plaster of Paris’’, or (vaguely scientifically) as ‘‘pumice’’. Bright ray craters appeared just as if they had been made by a ‘‘pickaxe striking concrete’’. The colour was varied, sometimes appearing to be black and white, yet other times displaying a distinctly brownish tan. In terms of mood, the surface was ‘‘desolate’’, ‘‘bleak’’ and ‘‘forbidding’’. A 9.6-second burn at 073:35:06.6 circularised the orbit at 60 nautical miles.

As this was the first opportunity for humans to directly observe the Moon at close range, James Sasser of the Apollo Spacecraft Project Office in Houston had served as the ‘project scientist’ for the mission. He formed an advisory team and this drew up a program of photography and visual observations for the crew to perform using a Maurer 16-mm movie camera and a Hasselblad with a 250-mm lens. In particular, the Manned Spacecraft Center wanted views of the eastern limb to assist in selecting landmarks for a lander’s navigational checks prior to the powered descent. Some of this documentation was to be overlapping vertical and oblique pictures which would enable stereoscopic analysis to determine the geographical position and elevation of each feature, but the movie camera was also to be fitted to the spacecraft’s sextant to depict the landmarks in context. In addition, some ‘scientific’ targets were marked on the flight charts as ‘targets of opportunity’ which were to be inspected if time and circumstances allowed. These were to provide either detailed coverage of specific features or broad coverage of areas which had not been adequately imaged by the Lunar Orbiters. And, of course, the ALS-1 landing site was to be inspected. Most of the scientific observing and photography was assigned to Anders, the LMP without a lunar module. Jack Schmitt, a professional geologist who was hired as an astronaut in 1965, served as the main interface between Sasser’s team and the Apollo 8 crew in training, but some briefings were provided by US Geological Survey staff. At the suggestion of Wilmot N. Hess, Director of the Science and Applications Directorate at the Manned Spacecraft Center, SasseTr’s team had set up a ‘science support’ room in Mission Control to listen to the astronauts’ commentaries and watch the TV of the lunar landscape passing below the spacecraft.

The astronauts could recognise surface features in shadows lit by Earthshine, and could see detail on sunward-facing slopes which had been ‘washed out’ in the Lunar Orbiter pictures. In fact, they could perceive detail to within 5 degrees of the ‘zero phase’ point, which is the line of sight with the Sun directly behind the observer. In planning the lunar landing the lower limit for Sun angle had been set at 6 degrees, but the astronauts could see surface detail at angles as low as 2 degrees. They were able to confirm that the upper limit of 16 degrees provided excellent definition, and their observations suggested that it might be possible to raise the limit to 20 degrees – but no higher than this. This enabled the lighting constraints for the lunar landing to be relaxed.

Of the two candidate landing sites in Mare Tranquillitatis, ALS-1 in the east was brighter; so much so, in fact, that it was debatable whether it was truly mare material or a flatfish portion of the adjacent terra. Observing it visually from an altitude of 60 nautical miles, Lovell said it reminded him of an aerial view of Pinacate in Mexico, a volcanic field which he had been shown in training.

Owing to crew fatigue, Frank Borman took the decision at 084:30 to cancel all secondary activities during the final two revolutions, to allow the crew to rest. The only tasks during this period were an alignment of the inertial guidance system and the preparations for transearth injection. But at 085:43:03 they provided the planned 27-minute TV transmission showing the Moon and Earth, and to mark the fact that it was Christmas Eve they recited the first ten verses of the Book of Genesis from the Bible prior to signing off with, ‘‘Good night, good luck, a Merry Christmas, and God bless all of you – all of you on the good Earth.’’

Radio tracking indicated that by the time Apollo 8 was ready to head for home the mascons had perturbed its initially circular orbit into one of 58.6 x 63.6 nautical miles. At 089:19:16.6, after ten revolutions of the Moon, the 203.7-second transearth injection was made on the far-side of the Moon at an altitude of 60.2 nautical miles, which was just about perfect. After returning to the Earth’s gravitational influence, the spacecraft progressively accelerated. Only one small midcourse correction was required. It was made at 104:00:00, and the 15.0-second burn by the service module reaction control system imparted a change of 4.8 ft/sec.

On shedding the service module, the command module adopted its entry attitude and at 146:46:12.8 hit the entry interface travelling at 36,221.1 ft/sec. It pursued an automatically guided profile. The ionisation bathed the interior of the cabin in a cold

An oblique view by Apollo 8 looking northwest across the eastern part of Mare Tranquillitatis. The crater in the foreground is Taruntius-F, and one of the Cauchy clefts crosses the upper part of the picture. The ALS-1 site is out of frame to the south.

blue light as bright as daylight. At 180,000 feet, as expected, the lift vector deflected the vehicle to 210,000 feet, then it resumed its downward course. It splashed into the Pacific 1.4 nautical miles from the target at 15:51:42 on 27 December. It adopted an apex-down position, but promptly righted itself. The astronauts were soon recovered and flown by helicopter to USS Yorktown.

This audacious mission, described as the “greatest voyage since Columbus”, took NASA a giant step towards achieving Kennedy’s challenge.

On 6 January 1969 Deke Slayton called Neil Armstrong, Michael Collins and Buzz Aldrin to his office at the Manned Spacecraft Center and told them that they would fly Apollo 11 and should assume their mission would involve a lunar landing.

On 10 January 1969 John Stevenson, Director of Mission Operations at the Office of Manned Space Flight, circulated a revised version of the tentative schedule for the year that was issued early in 1968. This called for launching the delayed ‘D’ mission on 28 February. As the ‘E’ mission had been rendered irrelevant by Apollo 8, this meant that if the ‘F’ mission flew in May and was satisfactory, it should be possible to attempt the lunar landing in July. The rationale for the ‘F’ mission was to obtain experience of operating in deep space, but after Apollo 8 the issue became whether another test in lunar orbit was required. The decision was postponed until LM-3 had been put through its paces.

THE SPIDER

Apollo 9 was to be the ‘D’ mission – a lunar module manned flight demonstration in Earth orbit. The payload for the AS-504 launch vehicle was CSM-104 and LM-3. As they were to operate independently, the spacecraft were given radio call-signs. The blue wrapping of the command module for its shipment to the Cape had given it the appearance of a sweet, so it was named ‘Gumdrop’. The arachnid-like configuration of the lunar module prompted the name ‘Spider’.

The launch was scheduled for 28 February 1969 and the countdown was begun at 03:00:00 GMT on 27 February with 28 hours on the clock, but 30 minutes into the planned 3-hour hold at T-16 hours the clock was recycled to T-42 hours in order to enable the crew of James McDivitt, David Scott and Rusty Schweickart to recover from a mild respiratory infection. The count picked up at 07:30:00 on 1 March and the vehicle lifted off from Pad 39A on time at 16:00:00 GMT on 3 March.

The ascent was nominal and at S-IVB cutoff at T+664.66 seconds the deviations were +2.86 ft/sec in velocity and -0.17 nautical mile in altitude, with the result that the initial orbit was almost perfect at 100 nautical miles. At 002:41:16.0 the S-IVB released the CSM, which moved clear, turned end over end to aim its apex at the top of the LM and moved back in. At 003:01:59.3 it docked at the first attempt, marking the first use of this apparatus. Once the tunnel between the two spacecraft had been pressurised, the crew opened the apex hatch of the command module to confirm that all the latches on the docking ring had engaged, and after lines had been connected to supply power to the dormant LM the hatch was reinstalled. On a command issued by the CSM at 004:08:09 the S-IVB released the docked combination.

Preparing the CSM-104 and LM-3 spacecraft for the Apollo 9 mission.

Apollo 9’s S-IVB with the Lunar Module ‘Spider’ exposed.

After the spacecraft was clear, the S-IVB reignited its engine at 004:45:55.5 to raise an apogee of 1,672 nautical miles. Then, after a period of coasting to allow the engine to cool down, it initiated a final burn at 006:07:19.3 to achieve a velocity of 31,620 ft/sec which would send it into solar orbit.

Meanwhile, at 005:59:01.1 a 5.2-second burn by the service propulsion system raised the spacecraft’s orbit to 111 x 128 nautical miles. Three further manoeuvres on the second day in space measured the oscillatory response of the docked vehicles to obtain data designed to improve the autopilot’s response in this configuration, and also burned off the CSM’s propellant to increase the fidelity of manoeuvres which it would later perform in Earth orbit to rehearse what a mission would do in lunar orbit.

On the third day in space, Schweickart entered the LM to check out its systems. McDivitt joined him 50 minutes later. At about 045:52, shortly after the landing gear was deployed, McDivitt advised Mission Control that Schweickart had twice been sick – this illness would have an impact on the EVA planned for later in the mission. At 046:28 the astronauts made a 5-minute TV transmission from inside the LM. The descent engine was ignited at 049:41:34.5 for a 371.5-second burn in which the autopilot controlled the attitude of the docked vehicles and the astronauts manually throttled the engine to full thrust. The LM was deactivated at 051:00. Several hours later, a service propulsion system burn achieved an almost circular orbit of 125.9 x 131.0 nautical miles in preparation for the rendezvous sequence.

The EVA plan had called for Schweickart to exit the LM’s forward hatch, transfer to the command module hatch, and then return. But owing to his bouts of nausea the spacewalk was cut back from 2 hours 15 minutes to just 39 minutes, to be made on a single daylight pass. The LM was depressurised at 072:45, and the hatch opened at 072:46. Schweickart initiated his egress at 72:59:02, feet first and face up, and was completely out by 073:07. He was wearing the Extravehicular Mobility Unit suit and Portable Life Support System backpack which astronauts were to wear on the lunar surface. A 25-foot nylon safety tether precluded him drifting away. For stability, he inserted his feet into a pair of ‘golden slippers’ on the ‘porch’ of the descent stage. Meanwhile, at 073:02:00 Scott opened the side hatch of the command module and poked his head and shoulders out to monitor Schweickart. Although the transfer to the command module hatch had been cancelled, Schweickart was able to make an abbreviated study of translation and body-attitude-control using handrails affixed to the upper part of the LM. Before ingressing, Schweickart shot 16-mm movie footage of Scott’s activities, and 70-mm Hasselblad pictures of the exterior of both vehicles. Although the EVA was brief and did not involve a period of orbital darkness, it was sufficient to certify the suit and backpack for use on the lunar surface. The LM was repressurised at 073:53, and the CSM several minutes later. After a TV transmission from the LM that started at 074:58:03 and lasted 15 minutes, it was deactivated and McDivitt and Schweickart rejoined Scott.

On the fifth flight day McDivitt and Schweickart were back in the LM by 088:55 in order to prepare that ship for a period of free flight and an active rendezvous. At 092:22 the CSM oriented the pair into the attitude required for undocking. This was attempted at 092:38, but the latches did not fully release until 092:39:36. This was to be the first time that astronauts flew a spacecraft that was incapable of returning to Earth if an emergency were to arise – they relied on Scott to rescue them. Once free, the LM pirouetted while Scott made a visual inspection. At 093:02:54 the CSM used the thrusters of its reaction control system to make a separation manoeuvre. Over the next 6.3 hours, the LM undertook a series of manoeuvres which set up and executed a rendezvous. In the process, the descent propulsion system was fired under different control regimes and with the throttle being varied, after which the descent stage was jettisoned and the rendezvous was performed by the ascent stage. Terminal phase braking began at 098:30:03, and was followed by a period of station-keeping, then formation flying to facilitate mutual photography prior to docking at 099:02:26. McDivitt and Schweickart then transferred back to the CSM. The ascent stage was jettisoned at 101:22:45.0, and half an hour later ignited its main engine and fired it to depletion to enter a 126.6 x 3,760.9-nautical mile orbit.

The remainder of the mission was less hectic, being devoted mainly to conducting multispectral photography to prepare for the Skylab space station. At 169:30:00.4 the service propulsion system was fired in a 24.9-second burn which established the conditions for a nominal de-orbit. Unfavorable weather in the planned recovery area prompted a postponement of the de-orbit by one revolution, and it was performed at 240:31:14.8. The service module was jettisoned a few minutes later. The command module flew the entry profile under the control of its primary guidance system, and splashed into the Atlantic at 17:00:54 on 13 March about 2.7 nautical miles from the target. It settled in the ideal apex-up flotation attitude, and within an hour the crew were onboard USS Guadalcanal.

DRESS REHEARSAL

With Apollo 9 having successfully tested the LM in Earth orbit, the next issue was whether to fly the ‘F’ mission or to push on and attempt the lunar landing. In fact, it would be impossible for LM-4 to attempt the ‘G’ mission, as the software to conduct the powered descent was still under development. Furthermore, owing to propellant restrictions in the ascent stage of this somewhat overweight LM it would be unable to lift off and rendezvous. Tom Stafford, the Apollo 10 commander, argued against his crew waiting for LM-5 to become available. ‘‘There are too many ‘unknowns’ up there,’’ he noted. ‘‘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.’’

On 24 March 1969 NASA stated that Apollo 10 would fly the ‘F’ mission. The original idea had called for the LM merely to undock, enter a slightly different orbit, rendezvous and redock, but in December 1968 the Mission Planning and Analysis Division at the Manned Spacecraft Center had urged putting the descent propulsion system through a high-fidelity rehearsal in which the LM would lower its perilune sufficiently to test the ability of the landing radar to detect and lock onto the surface. Howard Tindall also proposed that the LM should initiate the powered descent and then execute an early abort by ‘fire in the hole’ staging, but his colleagues convinced him that this would be too adventurous. One aspect of the decision to go ahead with the ‘F’ mission was to evaluate the tracking and communications of two vehicles in lunar orbit. In essence, it had been decided to exploit the fortuitous relaxation in schedule pressure and improve on Apollo 8 by performing a rehearsal to the point at which a later LM would initiate its powered descent.

The finally agreed plan called for the LM to separate from the CSM in the circular lunar parking orbit, enter an elliptical orbit having a perilune of about 50,000 feet located just east of the prime landing site, execute a low pass and then jettison the descent stage to make the rendezvous.

In April 1969 the site selectors met to decide the prime target for the first Apollo landing. The photographs of ALS-1 taken by Apollo 8 indicated the presence of a smooth blanket of light-toned material that softened or masked the landscape, and a study of the craters showed that the regolith was quite thick, which in turn implied a considerable age. The fact that the site was atypical of the maria made it unattractive for dating the maria, so it was rejected. This left ALS-2 in the southwestern part of Mare Tranquillitatis as the prime target. In early May, Jack Schmitt put it to Tom Stafford that the launch of Apollo 10 be slipped 24 hours from the proposed date so that the low-perilune pass over ALS-2 could be made in illumination matching that of a mission attempting to land there. This would enable high-resolution pictures to be taken of the site and the landmarks on the approach route. Stafford was receptive. Schmitt approached George Low, who asked Chris Kraft, who sought the advice of the flight control specialists – there were issues in favour and against. When the case was put to Sam Phillips he rescheduled the launch.

AS-505 had been installed on Pad 39B on 11 March, and Apollo 10 lifted off on schedule at 16:49:00 GMT on 18 May 1969 with Tom Stafford, John Young and Gene Cernan.

When the S-IVB cutoff at T + 703.76 seconds, the deviations were -0.23 ft/sec in velocity and -0.08 nautical miles in altitude. After translunar injection, CSM-106 ‘Charlie Brown’ separated, turned around and docked with LM-4 ‘Snoopy’, then the pair were released by the stage. The S-IVB then used propulsive venting to adopt a path that would fly past the Moon and enter solar orbit. At 026:32:56.8 the service propulsion system made a 49.2-ft/sec burn to match a July lunar landing trajectory. At 075:55:54.0 the spacecraft entered an initial lunar orbit of 60.2 x 170.0 nautical miles. Two revolutions later, this was refined to 59.2 x 61.0 nautical miles. During a 30-minute colour TV transmission the astronauts showed off the lunar surface. They reported the colour of the surface to be less grey than was described by Apollo 8. In particular, Mare Serenitatis appeared ‘‘tan’’, whereas Mare Tranquillitatis appeared ‘‘dark brown’’.

After undocking at 098:29:20, the vehicles took up station 30 feet apart while Young inspected the LM, and then the CSM moved off. A 27.4-second burn by the descent propulsion system at 099:46:01.6 placed the LM into a descent orbit with its perilune 15 degrees east of ALS-2. The landing radar was tested while passing over that site at an altitude of 47,400 feet an hour later. The pictures taken were of greater resolution than those transmitted by the Lunar Orbiters. Unfortunately, the 16-mm

This oblique view looking northwest across the crater Maskelyne was taken by the Apollo 10 Lunar Module ‘Snoopy’ as it flew low over Mare Tranquillitatis towards the ALS-2 target.

movie camera failed. A descent propulsion system burn at 100:58:25.9 put the LM into an orbit of 12.1 x 190.1 nautical miles to arrange a ‘lead angle’ equivalent to that which would occur at cutoff of an ascent from the lunar surface. At 102:44:49, during preparations to start the rendezvous with the CSM, the LM started to wallow off slowly in yaw and then stopped, and several seconds later it initiated a rapid roll accompanied by small pitch and yaw rates. Subsequent analysis revealed that this anomalous motion was due to human error. The control mode of the abort guidance system had inadvertently been returned to AUTO instead of the Attitude HOLD mode for staging. In AUTO, the abort guidance system steered the LM to enable the rendezvous radar to acquire the CSM, which at this point was not in accordance with the plan. The required attitude was re-established by the commander taking manual control. The descent stage was jettisoned at 102:45:16.9, and 10 minutes later an ascent propulsion system burn achieved an orbit of 11.0×46.5 nautical miles. This matched the insertion orbit for a mission returning from the surface. The LM had the active role in the rendezvous, and docked at 106:22:02. Two hours later the ascent stage was jettisoned, and during the next revolution the ascent propulsion system was fired to depletion in order to place the vehicle into solar orbit.

At 137:39:13.7, after 31 lunar revolutions, the CSM made the transearth injection. The aim was so accurate that it required only a 2.2-ft/sec refinement 3 hours prior to shedding the service module to centre the trajectory in the ‘corridor’ for atmospheric entry. The capsule splashed into the Pacific 1.3 nautical miles off target at 16:52:23 on 26 May and adopted the apex-up flotation attitude. The astronauts were aboard USS Princeton within the hour.

While Apollo 10 was in transit to the Moon, AS-506 was rolled out to Pad 39A in preparation for the Apollo 11 mission. After the pictures taken during the low pass over ALS-2 were examined, it was confirmed as the prime site for Apollo 11. ALS-3 in Sinus Medii was 2 day’s terminator travel westward and would be the backup. If the launch had to be delayed beyond the date for ALS-3, then the target would be ALS-5 in Oceanus Procellarum. In the post-flight debriefing, Tom Stafford pointed out that although the ALS-2 aim point was acceptable, the western end of the ellipse was much rougher. He advised Neil Armstrong that if he were to find himself at the far end of the ellipse and did not have the hover time to manoeuvre among the small craters and boulders to select a spot on which to land, then he would have to ‘‘shove off” – by which Stafford meant abort.

END GAME

A week before Apollo 11 was due to launch, people began to congregate at the Cape communities of Titusville, Cocoa Beach, Satellite Beach and Melbourne. They came from all around the world in order to be able to tell their grandchildren they were present when men set off to try to land on the Moon. By 15 July hotels and motels allowed late-comers to install camp beds in lounges and lobbies, but most people spent the night on the beaches and by the roadside, generating the worst congestion

in Florida’s history. With the notable exception of alarm clocks, which rapidly sold out, shops were able to supply the hoards. As it was to be a dawn launch, the parties ran through the night.

When AS-506 lifted off at 09:32:00 local time on 16 July on a mission to accept President Kennedy’s challenge of landing a man on the Moon before the decade was out, it was estimated that there were about a million people present and 1,000 times as many watching on ‘live’ television.

No-one could be certain that the objective would be achieved, but the way had certainly been well paved.

[1] He did not infer from the absence of detail in the shadows that the Moon was airless, nor did he suggest the presence of open water.

[2] In fact, one of the few names introduced by van Langren to have survived is Langrenus, by which he honoured his own family.

[3] Selene was the Greek moon-goddess.

[4] Like Herschel and Schroter, von Gruithuisen believed the Moon to be inhabited, and after using a small telescope he reported in 1824 his discovery of a city in the equatorial zone near the meridian; but this was later shown to be merely a group of shallow ridges that were visible only when the Sun was low on the local horizon.

[5] For over half a century, geologists had argued about how the Coon Butte crater formed – and this was for a structure that was accessible to in-situ examination. Could there be any hope of resolving the issue of the lunar craters, which could only be peered at from afar!?

[6] On transfer to NASA, the Langley Aeronautical Laboratory became the Langley Research Center, the Ames Aeronautical Laboratory became the Ames Research Center, the Lewis Flight Propulsion Laboratory became the Lewis Research Center and the High-Speed Flight Station became the Flight Research Center.

[7] On 3 December 1958 Eisenhower ordered that JPL be transferred to NASA. This took effect on 1 January 1959, although only under contract, since the facility was owned by Caltech, which NASA paid. In September 1959 the Pentagon voluntarily yielded the Army Ballistic Missile Agency since the military had decided it did not require the Saturn launch vehicle; it would develop the Titan III instead. On 21 October 1959 NASA announced that it was to gain von Braun’s rocket team. On 1 July 1960 the Army Ballistic Missile Agency became the Marshall Space Flight Center.

[8] Physicists James van Allen, Homer Newell, Charles Sonett and Lloyd Berkner were notable early members of the ‘sky science’ community.

[9] Colloquia were held quarterly at different venues on the West Coast through to May 1963.

[10] As would later be realised, Mare Moscoviense fills the floor of a 300-km-diameter crater and Tsiolkovsky covers a portion of the floor of a crater which has a prominent central peak.

[11] The name Ranger set a trend for lunar projects with the names Surveyor and Prospector; in contrast to Mariner for planetary missions – that is ‘land’ names as against ‘sea’ names.

[12] Later, launch operations would be made a separate field centre.

[13] In early 1962 the entire NASA launch organisation was restructured.

[14] The Soviet spacecraft fell silent on 27 February 1961, at a distance of 2З million km from Earth. A launch on 4 February had stranded a similar spacecraft in parking orbit, but its role was disguised by naming it Sputnik 7.

[15] Surface science was only one of the objectives; there were the investigations to be made during the terminal approach, and achieving these would mark an acceptable compromise on the first mission.

[16] They were Lieutenant Commander Alan Bartlett Shepard Jr, Lieutenant Malcolm Scott Carpenter and Lieutenant Commander Walter Marty Schirra Jr from the Navy; Lieutenant Colonel John Herschel Glenn Jr from the Marines; and Captain Virgil Ivan ‘Gus’ Grissom, Captain Donald Kent ‘Deke’ Slayton and Captain Leroy Gordon Cooper Jr from the Air Force.

[17] This reasoning would resurface when John F. Kennedy asked for a worthy challenge.

[18] In a reorganisation on 8 December 1959, the Office of Space Flight Development had become the Office of Space Flight Programs.

[19] In fact, NASA could have launched Shepard several weeks ahead of Gagarin’s flight. If this had been done, Kennedy may well not have issued the challenge of landing a man on the Moon before the decade was out. The fact that Shepard’s flight had been only suborbital whereas Gagarin’s was orbital, would probably not have mattered, since the world’s first ‘spaceman’ would have been an American. The fact that America ‘lost’ both the first satellite and the first man into space could be said to be directly responsible for the race to the Moon. It serves to illustrate that history is not an irresistible tide, it can be extremely sensitive to the outcome of singular events.

[20] Earth imparts a gravitational acceleration of 32.2 ft/sec2.

[21] Newell also wished to maximise the amount of science on manned flights in Earth orbit.

[22] Despite Gold’s assertion that the dust would react only slowly upon being loaded, reporters would remain fascinated by the possibility that a lander would rapidly become submerged by it!

[23] The crater made by Ranger 8 was photographed by Lunar Orbiter 2, and found to be about 13.5 metres in diameter with a mound at its centre.

[24] The converter was installed at JPL, not at Goldstone.

[25] The crater made by Ranger 9 was photographed by Apollo 16 in 1972. At 14 metres in diameter, it was similar to that of its predecessor.

[26] The delay in the Centaur stage was in part due to problems with the configuration of its propellant tanks, but also because the Marshall Space Flight Center was busy with the Saturn launch vehicles. In early 1962, therefore, the Centaur had been transferred to the Lewis Research Center.

[27] In the case of Lunar Orbiter, the wide-angle images would be referred to as medium (M) frames and the narrow-angle images as high-resolution (H) frames.

[28] In fact, Bimat was similar to the Polaroid process.

[29] In particularly, the Planetology Subcommittee called for the Lunar Orbiter Block II to undertake selenodesy, gamma-ray, X-ray, magnetometry, microwave and non-imaging radar studies from orbit.

[30] This was because on a direct ascent the translunar injection point was necessarily near the latitude of the launch site, and for a launch from Florida this was north of the equatorial plane on a southerly heading, which meant that by the time the spacecraft reached lunar distance it would be south of the equatorial plane.

[31] The Manned Space Flight Network was operated under the direction of the Goddard Space Flight Center in support of the Manned Spacecraft Center.

[32] In fact, stereoscopic analysis of the Lunar Orbiter pictures proved difficult due to the manner in which they were scanned in narrow strips for transmission, as this gave the impression of the surface as being corrugated.

[33] Whereas in summer the Moon reaches its ‘full’ phase south of the equator, in winter it does so north of the equator, and since for the early Surveyors the landing sites were well to the west of the lunar meridian with arrival soon after local sunrise in winter months the translunar injection had to be made from south of the Earth’s equator. The restartable Centaur facilitated this by using its first burn to achieve a parking orbit and, once south of the equator, using its second burn to head for the Moon.

[34] During a solar eclipse, when the Moon occults the Sun to terrestrial observers, the irregular profile of the lunar limb often allows light from small sections of the solar disk to be viewed during totality, giving rise to a phenomenon known as Baily’s Beads after the British astronomer Francis Baily who first noted them during an annular eclipse on 15 May 1836.

[35] The term ‘psia’ means pounds of force per square inch on an ‘absolute’ scale measured relative to zero. If a pressure gauge is calibrated to read zero in space, then at sea level on Earth it would read 14.7 psi, which is sea-level atmospheric pressure. A value specified in psia is therefore relative to vacuum, rather than a differential relative to the pressure at sea level on Earth. For large numbers, the difference is insignificant.

[36] The pictures taken by Lunar Orbiter 1 showing Earth against the lunar limb were in black – and-white.

[37] Both Apollo 15 and Apollo 17 were sent to sites imaged by Lunar Orbiter 5; although in the case of Apollo 17 the observations by Apollo 15 also contributed to the selection.

[38] In the late 1950s J. J. Gilvarry argued that the maria were once water oceans, and hosted life. He said the now-dry plains were sedimentary rock, and dark owing to the presence of organic material. He claimed the elemental abundance data from the alpha-scattering instrument matched mudstone even better than it did basalt.

[39] Although NASA was unaware of it, a gamma-ray spectrometer operated in lunar orbit by Luna 10 in 1966 had provided a rudimentary analysis of the composition of the lunar surface across a wide range of latitudes, and the results showed there to be no significant exposures of acidic rock in the highlands.

[40] The term ‘facies’ was introduced to geology in 1838 by the Swiss stratigrapher Amanz Gressly to specify a body of rock having given characteristics.

[41] They were: Lieutenant Charles ‘Pete’ Conrad Jr, Lieutenant Commander James Arthur Lovell Jr, and Lieutenant Commander John Watts Young from the Navy; Major Frank Frederick Borman II, Captain James Alton McDivitt, Captain Thomas Patten Stafford, and Captain Edward Higgins White II from the Air Force; Neil Alden Armstrong, a former naval aviator, now a civilian test pilot for NASA; and Elliot McKay See Jr, a civilian test pilot for the General Electric Company.

[42] Slayton had been grounded in 1962 owing to a heart irregularity while training for a Mercury mission.

[43] They were: Major Edwin Eugene ‘Buzz’ Aldrin Jr, Captain William Alison Anders, Captain Charles Arthur Bassett II, Captain Michael Collins, Captain Donn Fulton Eisele, Captain Theodore Cordy Freeman, and Captain David Randolph Scott from the Air Force; Lieutenant Alan LaVern Bean, Lieutenant Eugene Andrew Cernan, Lieutenant Roger Bruce Chaffee, and Lieutenant Commander Richard Francis Gordon Jr from the Navy; Captain Clifton Curtis Williams from the Marines; Ronnie Walter Cunningham, a research scientists at the RAND Corporation; and Russell Louis ‘Rusty’ Schweickart, a research scientist at the Massachusetts Institute of Technology.

[44] This name change officially took effect on 20 December 1963.

[45] On 26 October 1962 a nomenclature was introduced by which the pad abort tests were to run in sequence from PA-1; the Little Joe II flights were to start at A-001; missions using the Saturn I were to start at A-101; missions using the Saturn IB were to start at A-201; and missions using the Saturn V were to start at A-501, with the ‘A’ standing for ‘Apollo’. The ‘SA’ prefix was employed by the Marshall Space Flight Center (giving precedence to the launch vehicle) and the ‘AS’ prefix was used by the Manned Spacecraft Center (giving precedence to the spacecraft). In addition, the term ‘space vehicle’ was introduced to describe the integrated ‘launch vehicle’ and ‘spacecraft’, with the latter comprising the CSM, the LM (if present) and the SLA structure.

[46] NASA’s Flight Research Center at Edwards Air Force Base was renamed in Dryden’s honour.

[47] On 30 March 1967 George Low suggested that the AS-201 and AS-202 test flights be assigned the designations Apollo 2 and Apollo 3 retrospectively in order to fill in the gap, but this was rejected by Mueller on 24 April. AS-203 was not included because it did not carry a spacecraft.

[48] The last two categories represented the lunar part of the Apollo Applications Program which was being promoted by George Mueller, and when this fell by the wayside the reconnaissance surveys were deleted and the main program was expanded to include ‘enhanced capability’ landings.

[49] Times in this hhh:mm:ss format are with reference to the time of launch.

[50] It is worth noting that the guidance system in the IU performed this magnificent recovery entirely on its own.

[51] CSM-101 had flown on Apollo 7, CSM-102 had been retained by North American Aviation for ground testing, CSM-103 had been assigned to the Apollo 8 ‘C-prime’ mission, CSM-104 was to fly the Apollo 9 ‘D’ mission, CSM-105 was for ground testing, and CSM-106, which was delivered to the Cape on 25 November 1968, was assigned to Apollo 10.

MAPPING THE MOON

Jacob Floris van Langren founded a business in Amsterdam in 1586 which made globes, and as Dutch explorers reported discoveries he could barely keep up with the demand for updates. In 1627 his grandson, Michel van Langren, observed the Moon and made a sketch. After moving to Madrid as Court Astronomer to King Felipe IV of Spain in 1630, the grandson convinced the King that tables listing the sunrise and sunset times of specific lunar features would enable the time at the observing site to be determined, which would in turn solve the ‘longitude problem’. The prerequisite was a map of the Moon. In 1643, having made 30 sketches, van Langren realised he had competitors, so in 1645 he issued a whole-disk map 34 cm in diameter on which he named 325 features after prominent philosophers, mathematicians, astronomers, explorers, religious figures and (recognising his sponsor) members of the Spanish royal family. However, at that time the revolt of Protestantism which would later be called the Thirty Years War was well underway, and a nomenclature drawn from Catholic Europe was sure to be contentious.[2]

In 1637 Pierre Gassendi, a mathematician in Paris, also came to the conclusion that it should be possible to use observations of the Moon to determine the time and thereby resolve the ‘longitude problem’. After he had made some drawings, he heard that Johann Hevelius, whom he had once met, was starting to make a map, and upon seeing the quality of the younger man’s sketches Gassendi stopped and handed over his own work. A city councillor in Danzig in Poland, Hevelius built an observatory on the roof of his house and installed a telescope with a 5-cm-diameter lens, a focal length of 3.6 metres and a magnification of 50 – in fact, one of the best telescopes of the time. In 1647 he published Selenographica sive Lunae Descriptio, with fine drawings and a consolidated map 30 cm in diameter.[3] He named 275 features after terrestrial landforms, including oceans, seas, bays and lakes – although he realised there were no bodies of open water. Like Galileo, Hevelius estimated the heights of the lunar peaks by their shadows, but much more accurately. Being a Protestant, his nomenclature had little in common with that of van Langren. In fact, Hevelius had presumed himself to be the first to name features, and said the task was arduous. He

image6Ш7^ f

Подпись: . ЯПС^ммип Mtfr uhiufi»tвШ ь. ftti ttviat fiut W.VTW й^п,|ні тій<<_» ~~,1'“' “—[упчУіІігг/і - УДЧІХГ nwr/, I* Ьш*і« at Подпись:

MAPPING THE MOON
Подпись: rc"««.'4vcv
Подпись: .tn'tllV.

ШІІІ »Г«Ш л*1" V«…

‘ Піт.

Д-U^li iM ЛкЖсЛіШІ »Wfca«£e ■

ши: ГОфАМ WUJA ГЛд»>Т1П TAMES SVXASO
мшмліичшоуіампіА.

MICHAEL TLORENTIVe. LANGRENVS

The map of the Moon published by Michel van Langren in 1645 was the first to assign names to features.

image7

A map of the Moon published by Johann Hevelius in 1647.

honoured astronomers and scientists, including Gassendi, but not himself. However, only a dozen of his names have survived.

As a Jesuit professor of astronomy and theology at the University of Bologna, Giovanni Battista Riccioli believed implicitly in the Aristotlean system as written of by Ptolemy. In an effort to counter the growing belief that Earth travels around the Sun, he set out to write an authoritative account of astronomy. But while developing his argument he came to suspect he was wrong! He could never admit this publicly, however. In 1651 he published Almagestum Novum, with a whole-disk map of the Moon that was 28 cm in diameter and was based on observations made by his pupil, Francesco Maria Grimaldi. Although the map was little better than that by Hevelius, its historical significance was the nomenclature. This retained oceans, seas and bays for the dark areas, but renamed them for states of mind: e. g. Oceanus Procellarum and Mare Tranquillitatis. Craters were named after astronomers and philosophers, including Riccioli and Grimaldi. The despised Copernicus was assigned a crater in Oceanus Procellarum – the Ocean of Storms. To Helvelius’s frustration, soon copies of his map were in circulation relabelled with Riccioli’s nomenclature! Nearly all of the 200 names introduced by Riccioli and Grimaldi are still in use today.

Giovanni Domenico Cassini was born in 1625 in the Republic of Genoa. After a Jesuit education he was hired by the Marquis Cornelio Malvasia in Bologna, who

image8

A map of the Moon published by Giovanni Battista Riccioli in 1651.

derived ephemerides for astrological purposes. Utilising the excellent instruments of his employer’s observatory, Cassini made observations of exceptional precision and quality, and in 1650 became professor of astronomy at the University of Bologna. In 1666 plans were initiated to establish a national observatory in Paris, and in 1669 Cassini, now with several significant discoveries to his name, was invited by King Louis XIV to become its first director; he accepted and promptly moved to France to oversee the construction of the observatory, which was finished in 1671. In 1679 he published a map of the Moon which, at 52 cm in diameter, was much larger than its predecessors. Although very accurate, so few copies were made that it did not gain the attention which it warranted.

Meanwhile, Isaac Newton at the University of Cambridge in England had made a study of gravity and, contrary to the accepted wisdom that it remained constant

image9

A map of the Moon published by Giovanni Domenico Cassini in 1679.

with distance, realised that its strength declined with the inverse square of distance. His book Philosophiae Naturalis Principia Mathematica, published in 1687, provided a basis for the laws of planetary motion that Kepler had derived empirically.

The Moon was essentially ignored for a century, then Tobius Mayer in Germany became interested in its use in relation to the ‘longitude problem’. In 1751 he gained the chair of economics and mathematics at the University of Gottingen, where, a few years later, he became superintendent of the observatory. As a skilled draughtsman, he utilised a micrometer to measure the geographical positions of the lunar features. His map was published posthumously in 1775, and although only 20 cm in diameter it was the first to include lines of latitude and longitude. It superseded the map by Hevelius (re-annotated with the nomenclature of Riccioli) which had been standard for almost 150 years, and would itself not be surpassed for half a century.

image10

A map of the Moon by Tobius Mayer that was published posthumously in 1775.

William Herschel, who discovered the planet Uranus in 1781 and became the first president of the Royal Astronomical Society, did not devote much attention to the Moon. However, he believed it to possess an atmosphere (even though the way stars were occulted contradicted this) and active volcanoes. Although by now the idea of open water had been abandoned, Herschel was “absolutely certain” the Moon was inhabited.

Johann Hieronymus Schroter was born in 1745 in Erfurt in Germany. In 1767 he graduated in law from the University of Gottingen. In 1781 he moved to Lilienthal, near Bremen, to become chief magistrate. Having been inspired by Mayer’s map, he built an observatory alongside his house and installed a series of ever more powerful telescopes. Over a period of 30 years he made hundreds of detailed drawings of the Moon, recording individual features under different angles of illumination. In this respect, he founded modern selenography. He paid particular attention to craters and

rilles – both of which terms he introduced. His measurements of the heights of lunar peaks were better than those of his predecessors. Although an accurate observer, he was not a skilled draughtsman and utilised a ‘schematic’ style. In 1791 he published Selenotopographische Fragmente zur genauern Kenntniss der Mondflache in two volumes containing a total of 75 engravings. He did not consolidate his observations into a full – disk map, but did include an enlarged version of Mayer’s map. In 1813 the invading Napoleonic army ransacked and destroyed his observatory, and most of his unpublished work was lost. Schroter inferred the Moon to have an atmosphere, but estimated its pressure to be less than that of the best vacuum pump available at that time. Nevertheless, like Herschel, he believed the Moon to be inhabited.

Wilhelm G. Lohrmann was a surveyor in Dresden, and a skilled draughtsman. He had developed a keen interest in astronomy as a boy, and in 1821, aged 25, began to study the Moon. He set out to make a map in 25 sections on a scale at which the disk would be 95 cm in diameter. By 1824 he had released the first four sections, and by 1836 had the drawings for the remaining sections, but then his eyesight failed and he was unable to finish the editing. Nevertheless, in 1838 he published a full-disk map at 40 per cent scale.

Johann von Madler was born in 1794 and became a teacher in Berlin. One of his students, the wealthy banker Wilhelm Beer, was only a few years younger and they became friends. In 1829 Beer built an observatory at his house and bought a 95-mm – diameter refracting telescope produced by Joseph von Fraunhofer’s firm. Beer hired Madler as observer, and they measured almost 1,000 features to trigonometrically survey the Moon. Between 1834 and 1837 they published Mappa Selenographica in four parts, which together made a whole-disk map 95 cm in diameter. Owing to the recent improvement in telescopes, their map surpassed all its predecessors. In 1838 they republished the map with a dissertation in their book Der Mond. It became the definitive work on the subject, but their convincing argument for the Moon being an airless and unchanging body prompted a hiatus in observing.

While reading Schroter’s 1791 Selenotopographische Fragmente as a boy, J. F.J. Schmidt in Germany decided to study the Moon. After acting as assistant at various German observatories, in 1858 he became director of the Athens Observatory and set out to make a full-disk map with a diameter of 180 cm which would show more craters, rilles and mountains than its predecessors. In fact, for many years he was the only observer engaged in systematic lunar work! He completed the observations in 1868, having produced in excess of 1,000 sketches, measured the positions of over 4,000 points, catalogued 278 rilles and used shadow details to measure the depths of craters and the heights of mountains. When issued in 25 sections in 1874, the map specified 33,000 craters and the heights of 3,000 mountains. In 1878 he reprinted it in his book Charte der Gebirge des Mondes. Having acquired Lohrmann’s files, Schmidt had his predecessor’s map engraved at the scale originally intended, and in 1878 published it as Mondkarte in 25 Sektionen; it would have been a fine map for its time, but was now obsolete.

In 1864 the British Association established a Lunar Committee, but this achieved little. In 1876 Edmund Neville Nevill (using the surname Neison) published a book, The Moon, which included a full-disk map in 22 sections with a diameter of 60 cm. In fact, it was a reworking of Beer and Madler’s chart supplemented with a detailed description of each named feature – some 500 in all – making it a monumental work. It stimulated sufficient interest to prompt the establishment of the Selenographical Society with William Radcliffe Birt, one of the most active of British amateur lunar observers of that time, as president, and Neison as secretary. But it was disbanded in 1883 after the death of Birt in 1881 and the departure of Neison in 1882 to become the first director of the Natal Observatory in Durban in South Africa. Nevertheless, when the British Astronomical Association was established in London in 1890 the former members of the Selenographical Society set up a Lunar Section as a means of coordinating their activities. T. G. Elger, the Director of the Lunar Section, published a book entitled The Moon in 1895 to assist new observers.

By 1890 photography had matured sufficiently to facilitate surveys of the Moon. Two photographic atlases were published in 1897. Atlas Photographique de la Lune covered the whole face in many small sections using plates taken by Maurice Loewy at the Paris Observatory and text provided by his assistant Pierre Puiseux. The Lick Observatory Atlas of the Moon by Edward Singleton Holden comprised 19 sheets of reproduced photographs. After establishing a temporary astronomical outstation in Jamaica, W. H. Pickering of the Harvard College Observatory set himself the task of photographing the lunar disk in several sections at five illumination phases. When The Moon – A summary of existing knowledge of our satellite, with a complete photographic atlas was published in 1903 it was the first true atlas, because the pictures were reproduced at the same scale. Although Jamaica had particularly clear skies, Pickering’s pictures of the Moon were still blurry and so there remained scope for visual studies, particularly in the limb regions – but as professional astronomers turned their attention to the stars and even more distant objects, they left the Moon, which they regarded as a source of ‘light pollution’, to their amateur brethren.

On the nights of 12 to 15 September 1919 Francis Pease photographed the Moon while testing the new 100-inch Hooker reflector at the Mount Wilson Observatory in California. Walter Goodacre was born in 1856, lived in London, and developed an interest in astronomy as a boy. In 1910, after making thousands of observations, he compiled a whole-disk map of the Moon almost 200 cm in diameter. In 1931, by which time he had replaced T. G. Elger as Director of the Lunar Section of the British Astronomical Association, he published The Moon. It featured a map which combined fine detail obtained by visual observing in good ‘seeing’, with positional accuracy derived from the Mount Wilson photographs, but few copies were issued.

The International Astronomical Union was established in 1919 to oversee general issues, and it took responsibility for regulating lunar nomenclature.

KENNEDY’S CHALLENGE

NASA was well placed to exploit the new administration’s willingness to expand the space program. Its long-term planning was impressive for its detail, in particular

This report was excerpted in the New York Times on 12 January 1961, and is sometimes wrongly dated as such.

because George Low’s committee had costed the accelerated plan – concluding that it would require $7 billion to land a man on the Moon by the end of the decade. In January 1961 Low briefed Keith Glennan on the forthcoming hearings for NASA’s budget, but Glennan expected to be replaced by the new administration and so was in a weak position.

On Johnson becoming Kennedy’s Vice President, Robert S. Kerr took over from him the chairmanship of the Senate Committee on Aeronautical and Space Sciences. After consulting Kerr, Johnson recommended James E. Webb to succeed Glennan as NASA administrator, and Webb took over on 14 February. Whereas Glennan was a scientific administrator with a conservative outlook, Webb was a political operator. He had served as Director of the Bureau of the Budget between 1946 and 1949 and Undersecretary of State from then until 1952 in the Truman administration. He had been a director of Kerr’s oil and uranium conglomerate, Kerr-McGee Oil Industries, and simultaneously a director of the McDonnell Aircraft Company.

Webb immediately set out to obtain the funding that was earlier denied for Apollo and the Saturn launch vehicle. When the Bureau of Budget refused, Webb wrote to Kennedy in early March that Eisenhower had “emasculated the 10-Year Plan before it was one year old’’, and if the funding were not made available it would “guarantee that the Russians will, for the next five to ten years, beat us to every exploratory space flight’’. To ram home the message in terms that Kennedy would appreciate, Webb said, “We have already felt the effects of the fact that they were the first to place a satellite into orbit, have intercepted the Moon, photographed the back side of the Moon, and have sent a large spacecraft to Venus. They can now orbit seven and a half ton vehicles about the Earth, compared to our two and a half tons, and they have successfully recovered animals from flights of as much as 24 hours. Their present position is one from which further substantial accomplishments can be expected, and our best information points to a steadily increasing pace of successful effort on a realistic timetable.’’

On 23 March Kennedy met with Lyndon Johnson, Jerome Wiesner, David Bell of the Bureau of Budget and Edward C. Welsh, a former aide to Johnson who was now serving as Executive Director of the National Aeronautics and Space Council, of which Johnson was chairman. Kennedy agreed to increase funding for the Saturn launch vehicle, but said he would need to deliberate further on the Apollo spacecraft – he would decide in the autumn, he said.

Just when NASA began to think that it might beat the Soviets to a manned space flight, on 12 April 1961 Yuri Alexseyevich Gagarin made a single orbit and landed safely. Webb told Congress, in budget hearings then underway, that NASA could certainly work faster if its funding was increased.

The next evening Kennedy met at the White House with Jerome Wiesner, David Bell, James Webb, Hugh Dryden, Theodore Sorensen, who was a friend and advisor, and Hugh Sidey, a journalist for Life magazine who was one of Kennedy’s friends, and put to them the question, “at what point we can overtake the Russians’’. NASA opened with a space station to be assembled in Earth orbit to serve as a jumping off point for a future mission to the Moon. But, it pointed out, if the Soviets were on the same plan they would likely remain in the lead for some considerable time. Kennedy

Гro.’ere Index

 

KENNEDY’S CHALLENGE
KENNEDY’S CHALLENGE
KENNEDY’S CHALLENGE
KENNEDY’S CHALLENGE

Deny

 

Reds Win Running Lead In Race To Control Space ^ 7:

 

T—

 

The Huntsville Times reports the first man in space.

 

image32

wanted to minimise this period, either by accelerating or by short circuiting the plan. Dryden said a ‘crash’ program might land a man on the Moon ahead of the Soviets, but it might cost as much as $40 billion. ‘‘The cost! That’s what gets me,’’ Kennedy mused. ‘‘When we know more, I can decide if it’s worth it or not. If somebody can just tell me how to catch up.’’ As the meeting broke up, Sorensen remained behind to discuss what had been said, and upon emerging told the others, ‘‘We’re going to the Moon!’’

On 19 April Kennedy summoned Johnson and told him he had decided to issue a momentous challenge. The next day, Kennedy sent a memo to Johnson seeking ‘‘an overall survey of where we stand in space’’. Specifically:

1. Do we have a chance of beating the Soviets by putting a laboratory in space, or by a trip around the moon, or by a rocket to land on the moon, or by a rocket to go to the moon and back with a man. Is there any other space program which promises dramatic results in which we could win?

2. How much additional would it cost?

3. Are we working 24 hours a day on existing programs. If not, why not? If not, will you make recommendations to me as to how work can be speeded up.

4. In building large boosters should we put [our] emphasis on nuclear, chemical or liquid fuel, or a combination of these three?

5. Are we making maximum effort? Are we achieving necessary results?

On 21 April Kennedy told reporters that his administration was considering the options and cost of space, and said, ‘‘If we can get to the Moon before the Russians, we should.’’

Johnson consulted NASA first, which said there was little chance of beating the Russians to a space station; it might be possible to beat them to lunar orbit; the best bet was a lunar landing. This matched Johnson’s thinking. NASA suggested 1967 as a target date because it was expected that the Soviets would attempt to make a lunar landing then in order to mark the 50th anniversary of the Bolshevik Revolution. As a result of the additional analysis by Low, the costing had been increased from the $7 billion estimate for a landing in 1969 to $22 billion; but a landing in 1967 would be $34 billion. Next, Johnson consulted the Pentagon, and the Air Force agreed that a manned lunar landing would be appropriate – even although the Air Force would not be allowed to perform it. Finally, Johnson consulted three businessmen whose judgement he trusted: Frank Stanton of the Columbia Broadcasting System; Donald Cook of the American Electric Power Service Corporation; and George Brown of Brown and Root, which was a construction company in Texas. The fact that none of them was involved in the aerospace industry that would be called upon to build the hardware for the program was a point in their favour, since it meant they were unbiased. At the National Aeronautics and Space Council on 24 April, Johnson, as Wiesner later described it, ‘‘went around the room saying, ‘We’ve got a terribly important decision to make. Shall we put a man on the Moon?’ And everybody said ‘yes’. And he said ‘Thank you’.’’

The scientific community was represented in the White House by Wiesner. The majority of space scientists were interested in particles and fields, and because this

Подпись: In accordance with our conversation I would like for you aa

Chairman of the Space Council to be in charge of making an overall survey of where we stand in apace.

1. Do we have a chance of beating the Soviets by putting a laboratory in space, or by a trip around the moon, pr by a rocket to land on the moon, or by a rocket to go to the moon and back with a man. Is there any other space program which promises dramatic results in which we could win?

2. How much additional would it cost?

3. Are we working 24 hours a day on existing programs. If not, why not? If not, will you make reconmenda – tions to me as to how work can be speeded up.

Д. In building large boosters should we put out

emphasis on nuclear, chemical or liquid fuel, or a confcination of these three?

5. Are we making maximum effort? Are we achieving necessary results?

Подпись: and other responsible officials to cooperate with you fully. I would appreciate a report on this at the earliest possible moment.

image33,image34

I have asked Jim Webb, Dr. Wiesner, Secretary McNamara

/в/ John F. Kennedy

The historic memo to Lyndon B. Johnson which led John F. Kennedy to challenge his nation to land a man on the Moon before the decade was out.

research did not require a human presence, money spent on sending men into space was by definition wasted. But Kennedy wanted “dramatic results” and the scientists were unable to offer this. To be fair, Kennedy invited Wiesner to suggest a terrestrial challenge that would serve the purpose, “… something with an overseas impact, like desalination or feeding the hungry”. However, Wiesner could see that the Moon was

shaping up to be the challenge, and advised the President “never to refer publicly to the Moon landing as a scientific enterprise”.

On 28 April Johnson submitted the National Aeronautics and Space Council’s recommendation:

Largely due to their concerted efforts and their earlier emphasis upon the development of large rocket engines, the Soviets are ahead of the United States in world prestige attained through impressive technological accomplishments in space. The US has greater resources than the USSR, etc. The country should be realistic and recognize that other nations, regardless of their appreciation of our idealistic values, will tend to align themselves with a country which they believe will be the world leader. The US can, if it will firm up its objectives and employ its resources, have a reasonable chance of attaining world leadership in space. If we don’t make a strong effort now, the time will soon be reached when the margin of control over space and other men’s minds through space accomplishment will have swung so far on the Russian side that we will not be able to catch up. Even in those areas in which the Soviets already have the capability to be first and are likely to improve upon such capability, the United States should make aggressive efforts, as the technological gains as well as the international rewards are essential steps in gaining leadership. Manned exploration of the Moon, for example, is not only an achievement with great national propaganda value, but is essential as an objective, whether or not we are first in its accomplishment – and we may be able to be first.

Kennedy was receptive to Johnson’s recommendation, but he postponed a formal decision until after the first manned Mercury mission, which came on Friday, 5 May 1961 when Al Shepard rode a Redstone missile on a suborbital arc.[19]

Over the weekend, Johnson met James Webb and Secretary of Defense Robert S. McNamara to draw up a formal recommendation to Kennedy’s memo of 20 April. Recommendations for our National Space Program: Changes, Policies and Goals, jointly authored by Webb and McNamara, said, “It is man, not merely machines, in space that captures the imagination of the world. All large-scale projects require the mobilization of resources on a national scale. They require the development and successful application of the most advanced technologies. Dramatic achievements in space, therefore, symbolize the technological power and organizing capacity of a nation. It is for reasons such as these that major achievements in space contribute to

KENNEDY’S CHALLENGE

image35

On 5 May 1961 a Redstone rocket lifts off with a Mercury capsule containing Alan B. Shepard for a suborbital mission.

 

image36

After his successful Mercury flight, Alan B. Shepard shakes hands with John F. Kennedy at the White House.

 

Подпись: 80 The Apollo commitment

In a speech to Congress on 25 May 1961 John F. Kennedy challenged his nation to land a man on the Moon before the decade was out.

image37national prestige.” They wrote, “even though the scientific, commercial or military value of [such an] undertaking may by ordinary standards be marginal or economically unjustified”, it nevertheless generated “national prestige”, which had value in its own right. Furthermore, “The non-military, non-commercial, non­scientific but ‘civilian’ projects such as lunar and planetary exploration are, in this sense, part of the battle along the fluid front of the Cold War.’’ This echoed Kennedy’s criticism of Eisenhower: whereas Eisenhower had been conscious of the cost and dismissive of national prestige, to Kennedy national prestige was the issue and the cost was secondary.

On 25 May Kennedy gave a speech to a joint session of Congress on the theme of Urgent National Needs. In view of recent space achievements by the Soviets, he proclaimed, ‘‘Now it is time to take longer strides, time for a great new American enterprise, time for this nation to take a clearly leading role in space achievement, which in many ways may hold the key to our future on Earth.’’ Having outlined the political background, he laid down the gauntlet. ‘‘I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon, and returning him, safely, to the Earth.’’ He had opted for a lunar landing precisely because it posed a great technical challenge. By literally ‘shooting for the Moon’, he was betting that America would not only catch up with the Soviet Union in space, but forge ahead. Having concluded that space was the arena of superpower politics, he was challenging his rival, Nikita Khrushchev, for world leadership. He had imposed the deadline to ensure that reaching the Moon was perceived as a race. He was also well aware of the magnitude of the task. ‘‘No single space project in this

period will be more impressive to mankind, or more important for the long-range exploration of space; and none will be so difficult or expensive to accomplish.” The sending of a man to the Moon was to be the modern form of the ancient practice of ‘single combat’, whereby opposing armies lined up and each dispatched a single warrior to decide the issue. To indicate that it was a matter of national honour, he added, ‘‘In a very real sense, it will not be one man going to the Moon; if we make this judgment affirmatively it will be an entire nation, for all of us must work to put him there.’’ And in order to emphasise what was at stake, he warned, ‘‘If we are to go only halfway, or reduce our sights in the face of difficulty, in my judgment it would be better not to go at all.’’

For Kennedy the Moon was a symbol and, in terms of what he wished to achieve it was an excellent symbol. He had the impression that the applause in Congress was ‘‘something less than enthusiastic”, as he told Sorensen immediately after giving the speech. But Johnson had read the mood well: there was only minor opposition in the House of Representatives, and the debate in the Senate lasted less than an hour – only five of the 96 senators spoke, and the floor was dominated by Robert Kerr, who was Johnson’s man. NASA’s budget was doubled without a formal vote being taken.

Developing Lunar Orbiter

CHANGING HORSES

In January 1961 the Hughes Aircraft Company was selected to build the Surveyor spacecraft. With a planned mass of about 1,125 kg at translunar injection, it would require the Atlas-Centaur. The plan was for the orbital version to provide wide-area mapping and reconnaissance of potential landing sites for the surface Surveyors and, later, for Apollo. The mass at touchdown was expected to be about 340 kg, of which 114 kg would be scientific instruments which would not only transmit pictures but also provide data on the physical, chemical, mineralogical and biological properties of the surface material. The initial schedule called for the first flight in 1964. It was also envisaged that as the project matured, an orbital variant would be equipped to serve as a communications relay for landers investigating sites on the far-side of the Moon.

On 23 March the Lunar Science Subcommittee at the Office of Space Sciences recommended that the orbiter have a TV system which was capable of providing: (1) full coverage of the limb areas (highly foreshortened to terrestrial observers) and of the far-side at a resolution of 1 km, (2) wide-area reconnaissance at a resolution of 100 metres, and (3) stereoscopic pairs of selected areas with sufficient resolution to discern objects 10 metres in size. On 5 December Charles Sonett, Chief of Lunar and Planetary Sciences at the Office of Space Sciences, asked William Cunningham to determine the status of the orbiter. On 12 January 1962 Cunningham reported that JPL would not be able simply to adapt the vidicon system developed for Ranger; a new TV system would be required, the development of which had not yet begun.

NASA called for JPL to define the design requirements for the Surveyor orbiter, maximising its commonality with the lander, by 1 September 1962, but owing to the problems the laboratory was facing with Ranger the orbiter received little attention.

Meanwhile, on 15 June 1962 the Office of Manned Space Flight compiled a list of the data that it required the Office of Space Sciences to supply on the environment around the Moon and on its surface – i. e. Brainerd Holmes’s Requirements for Data in Support of Apollo. In view of the urgency to feed such information into the design

of the Apollo vehicles, the Office of Space Sciences asked JPL whether Ranger could serve as the basis for an orbiter. JPL in turn asked the Hughes Aircraft Company to consider the possibility of a 360-kg orbiter which could be launched by the Atlas – Agena. Hughes replied that in order to meet this mass limit, the scientific payload could not exceed 27 kg, which was unrealistic in view of the activity to be pursued. JPL calculated that if the solid-rocket motor that Surveyor was to use in the initial phase of its descent to the Moon were to be used to augment the Agena in the translunar injection, it would be possible to increase the scientific payload to 57 kg, but this was still too little. Even although the development of the Centaur stage was running behind schedule, the Office of Space Sciences decided to proceed with the Centaur-based orbiter.[26] To meet the Apollo requirements, the orbiter would require to provide photography of potential landing sites capable of revealing protuberances and pits as small as 1 metre in size and slopes as shallow as 7 degrees. But even the stereoscopic views from the Surveyor orbiter’s TV system would have a resolution no better than 10 metres. A photographic system employing film would be needed to meet the requirements of the Office of Manned Space Flight.

On 21 September 1962 Oran Nicks, Director of Lunar and Planetary Programs in the Office of Space Sciences, asked Lee R. Scherer to form a committee to evaluate proposals which had been submitted by the Space Technology Laboratories and the Radio Corporation of America for a ‘lightweight’ lunar orbiter compatible with the Atlas-Agena.

On 23 October Joseph Shea, the Deputy Director of the Office of Manned Space Flight, specified the relative priorities of the data that Apollo would require from the Office of Space Sciences. There was a greater need for the information which a soft – lander would provide, since this would feed into the design of the Apollo vehicles, whereas the information from an orbiter would not be required until later, in mission planning. Shea stressed that if funding was tight in Fiscal Year 1963, then the Office of Space Sciences should favour the lander over the orbiter.

Scherer reported to Nicks on the issue of an Agena-based orbiter on 25 October. The proposal by the Radio Corporation of America was for a Ranger bus to make a lunar flyby, dropping off a 200-kg package which would insert itself into orbit. The orbiter would be 3-axis stabilised and use a vidicon system (no doubt a development of the camera the company had provided for Ranger Block II) to provide pictures at a resolution of 130 metres in the wide-angle coverage and 30 metres in the narrow – angle coverage. The Space Technology Laboratories had envisaged an orbiter with a mass of 320 kg. It would have a monopropellant engine which was capable of firing several times. In addition to a midcourse manoeuvre and orbit insertion, this engine would permit changes to the orbit. One mission profile would be to enter a circular polar orbit at an altitude of 1,600 km and map the entire Moon, resolving objects as small as 18 metres in size. Alternatively, it could be placed into equatorial orbit at an altitude of 40 km to photograph that zone with a resolution of 0.5 metre. It would be spin-stabilised, and use a ‘spin scan’ camera of a design similar to that proposed by the RAND Corporation in 1958. It would use film to obtain a higher resolution than was obtainable using a vidicon. Scherer reported that only the proposal by the Space Technology Laboratories offered the prospect of meeting the requirements set by the Office of Manned Space Flight for imaging resolution, and he recommended that the company further refine the concept so as to enable the Office of Space Sciences ‘‘to establish the confidence needed [to consider] a flight program of this type, should it be deemed preferable to a Centaur-based orbiter’’. In fact, once the viability of an Agena-based reconnaissance orbiter had been established, this in itself undermined the case for pursuing the Surveyor orbiter.

On 26 October, Clifford Cummings, unaware of Scherer’s study, wrote to advise Oran Nicks that JPL was about to conduct a study to refine the configuration of the Surveyor orbiter in order to specify how it would perform its mission. In his reply on 8 November, Nicks pointed out that the Office of Space Sciences was looking into the possibility of an Agena-based orbiter.

On 2 January 1963 Nicks asked Floyd L. Thompson, the Director of the Langley Research Center, to consider the possibility of his staff taking on the development of a lightweight orbiter. Thompson set up an internal feasibility study. After the Space Technology Laboratories had refined its concept, a review was held at Langley on 25 February involving representatives of the company, the Office of Space Sciences, the Office of Manned Space Flight, Langley and Bellcomm. Lee Scherer and Gene Shoemaker reported on a study they had undertaken for Nicks to determine how a lightweight orbiter might satisfy the photographic requirements of Apollo. Dennis Jones of Bellcomm reported an assessment made for Shea on the degree to which an orbiter might support the manned and unmanned exploration of the Moon. A second meeting on 5 March agreed that not only was a lightweight orbiter viable, it would also significantly support Apollo. Langley then sent a delegation headed by Clinton E. Brown to brief Robert Seamans and present the case for Langley taking on such a project; Seamans authorised planning to proceed.

In order to assist Langley draw up the request for proposals, in April 1963 the Office of Manned Space Flight refined its requirements. The critical needs were: (1) data on the radiation flux in lunar space over a typical 2-week period; (2) a summary and analysis of all efforts for short-term prediction of severe solar proton events; (3) measurements of particles capable of penetrating 0.01 cm and 0.1 cm of aluminium in an average peak 2-week period of micrometeoroid activity; and (4) photographic data capable of showing protuberances 3.5 metres tall and slopes of 15 degrees in an area of the lunar surface with a radius of 60 metres (to be provided by the autumn of 1965) and then equivalent data showing 50-cm protuberances and 8-degree slopes in an area with a radius of 1,600 metres. Other needs were: (1) measurements of the distribution of slopes greater than 15 degrees in areas of 3.5 metres radius; and (2) the greatest possible coverage of the zone within 5 degrees of the lunar equator with a resolution of 25 metres or better.

On 25 April Edgar Cortright put it to Homer Newell that since one successful orbiter could be worth “dozens of successful Ranger TV impactors”, the three new Rangers which had recently been funded in order to obtain high-resolution pictures and gamma-ray and radar reflectance data on the Moon should be cancelled. Newell accepted this reasoning and passed the recommendation to Robert Seamans, who concurred on 12 July. Later in the year, the second batch of rough landing Rangers was also cancelled.

EARLY UNMANNED TESTING

AS-201 was the first in a series of test flights to ‘man rate’ the Saturn IB and the Apollo spacecraft.8 It lifted off from Pad 34 at 16:12:01 GMT on 26 February 1966. After the booster cut off, the S-IVB stage separated cleanly and attained the planned suborbital arc. In releasing CSM-009, the stage splayed its four panels to an angle of 45 degrees to allow the service propulsion system engine an unobstructed exit. The spacecraft had neither a guidance and navigation system nor an S-Band transmission system. It was powered by batteries instead of fuel cells, had a 20 per cent propellant load, and an ad hoc electromechanical control sequencer. It began by firing its RCS thrusters for 18 seconds to withdraw from the S-IVB. Upon peaking at an altitude of 226 nautical miles, the spacecraft fired its thrusters again to provide ullage to settle the propellants in their tanks, then fired the service propulsion system. However, 80 seconds into the planned 184-second burn the thrust chamber pressure started to decline owing to inadvertent helium ingestion, and by the time the engine shut down the pressure had declined to 70 per cent. The thrusters were immediately fired for ullage and the engine was reignited for a 10-second burn, during which the chamber pressure oscillated from 70 per cent down to 12 per cent.

At this point, CSM-002 was the only production-line spacecraft to have flown – it was launched on 20 January 1966 at the White Sands Missile Range by a Little Joe II booster as a high-altitude abort test.

Although the manoeuvres on the descending side of the arc were designed to drive the spacecraft into the atmosphere at a speed significantly faster than a normal orbital entry, it was still not as fast as a trajectory returning from the Moon. Several seconds later, the thrusters began a pitch manoeuvre at a rate of 5 degrees per second for 18 seconds to yield a 90-degree change in attitude. On separating, the command module used its own thrusters to continue this pitch rotation for an additional 82.5 degrees and then rolled 180 degrees in order to orient its heat shield for atmospheric entry. The plan was to subject the heat shield to a high heating rate – meaning a high temperature for a comparatively short time – but the velocity at entry was 782 ft/sec slower than the planned 29,000 ft/sec and the flight path was 0.44 degree shallower, with the result that the heating rate was less than that intended. Although the deceleration peaked at 14.3 g rather than 16.0 g, it was still much greater than on an operational mission. A fault in the electrical power system ruled out aerodynamic steering, and the ‘rolling’ entry which resulted was 40 nautical miles short. Some 37 minutes after launch, the command module splashed into the South Atlantic. It was recovered 2.5 hours later by USS Boxer. To allow the time to diagnose and rectify the fault in the service propulsion system, AS-202 was rescheduled to follow AS-203, which, as an S-IVB development flight, would not carry a spacecraft.

The docking by Gemini 8 with its Agena target vehicle on 16 March lent support to the decision to try the AS-207/208 dual mission. On 21 March NASA announced that Gus Grissom was to command the first Apollo mission. He would fly CSM-012 with Ed White and Roger Chaffee. They were to be backed up by James McDivitt, David Scott and Rusty Schweickart respectively. In each case, the commander and senior pilot were Gemini veterans and the third man was a rookie. Deke Slayton earmarked Grissom for this role immediately after the Gemini 3 test flight in March 1965. After commanding Gemini 4 in June 1965, McDivitt was reassigned to back up Grissom. White, who flew with McDivitt on Gemini 4, backed up Gemini 7 in December 1965 and then joined Grissom’s crew. Although Slayton was introducing a ‘rotation’ for Gemini in which a pilot could progress through backup to command a later mission, after flying Gemini 8 Scott was immediately assigned to McDivitt’s crew to enable them to obtain early experience of Apollo training prior to attempting the AS-207/208 dual mission. If CSM-011 demonstrated that the problems suffered by CSM-009 had been fixed, then AS-204 would launch CSM-012 in the last quarter of 1966 on an ‘open ended’ mission of up to 14 days ‘‘to demonstrate spacecraft and crew operations and evaluate spacecraft hardware performance in Earth orbit’’, but if there were significant issues outstanding then CSM-012 would be modified for a third unmanned test.

On 4 April 1966 the Manned Spacecraft Center revised its senior management job titles, replacing ‘assistant director for’ with ‘director of’ in order to make explicit the fact that the post had primary rather than subordinate responsibility for that activity. Thus, for example, Kraft ceased to be the Assistant Director for Flight Operations and became the Director of Flight Operations. On 12 May NASA deleted the word ‘Excursion’ from ‘LEM’, to make the lander the Lunar Module ‘LM’. On 25 May, precisely 5 years after President Kennedy made his speech to Congress calling for a lunar landing, a diesel-powered crawler carried the 500-F engineering model of the

Apollo-Saturn V at a maximum speed of 1 mile per hour from the vast cube of the Vehicle Assembly Building a distance of 3.5 miles on a special causeway to Pad 39 on the Merritt Island Launch Area in order to verify the ground facilities and assist in the development of training procedures. It was an awesome demonstration of the ‘mobile launcher’ concept.

AS-203 lifted off from Pad 37 at 14:53:17 GMT on 5 July 1966 and the S-IVB inserted itself into the desired circular orbit at an altitude of 100 nautical miles. As it did not have a spacecraft, an aerodynamic nose cone was used. At orbit insertion the liquid hydrogen was ‘settled’ by a combination of tank baffles and deflectors and by ullage induced by venting liquid oxygen. A TV camera in the fuel tank then verified that continuous venting of liquid hydrogen could hold the fluid in this condition during a coasting phase that approximated a flight heading for translunar injection. The fact that the rise in the liquid hydrogen pressure in orbit was greater than predicted gave data on the heat transfer properties of the tank that would be applied in planning Saturn V missions. Radar tracking by ground stations monitored how the parameters of the orbit were changed by the thrusting effect of continuous venting. A simulated restart of the J-2 engine verified the charging of the restart bottles at orbital insertion cutoff, the fuel recirculation chill – down, the fuel antivortex screen, and the liquid oxygen recirculation chill-down. A subcritical cryogenic nitrogen experiment carried in the nose cap successfully maintained pressure control, with a progressive decrease in the fluid quantity indicating that vapour was being uniformly delivered from a two-phase mixture. To save weight, the S-IVB had been designed such that its propellant tanks shared a bulkhead. This sophisticated structure had to cope with the normal difference in pressure between the tanks and also insulate the liquid oxygen at -172°C from the liquid hydrogen at -253°C to preclude the oxygen solidifying. After the ullage trial of the first revolution, the hydrogen valves were closed and the oxygen valves opened to space in order to place an inverse pressure on the common bulkhead and assess its predicted failure point – when this occurred early on the fifth revolution it caused the vehicle to break up.

On 13 July 1966 Deke Slayton and Chris Kraft jointly wrote to Joseph Shea, the Apollo Spacecraft Program Manager: ‘‘A comprehensive examination of the Apollo missions leading to the lunar landing indicates there is a considerable discontinuity between the missions AS-205 and AS-207/208. Both missions AS-204 and AS-205 are essentially long-duration system validation flights. AS-207/208 is the first of a series of very complicated missions. A valid operational requirement [therefore] exists to include an optical equi-period rendezvous on AS-205.’’ If this Block I flight were to include a rendezvous with its spent S-IVB, it would offer an opportunity to evaluate the control dynamics, visibility, and piloting techniques for the rendezvous phase of AS-207/208. By this point, every spacecraft on Grumman’s production line through to LM-4 was late. The focus, of course, was on LM-1, but late shipments by subcontractors were impeding its assembly. Nevertheless, the ‘rate of slippage’ was slowing, and on 6 October Shea reported his expectation that the company would be able to deliver LM-1 early in 1967. By the end of 1966 LM-1 and LM-2 were in test stands, and LM-3 through LM-7 were in various stages of assembly, but by the end

of January 1967 it was clear that LM-1 would not be able to be shipped on schedule in February.

As its designation suggests, AS-202 was intended to be the second Saturn IB test, but it slipped behind AS-203 as a result of delays involving the spacecraft. CSM-011 was a fully functional Block I spacecraft, minus the crew equipment. But it carried a more sophisticated ad hoc sequencer than on AS-201, a 60 per cent propellant load, a variety of flight qualification instrumentation and four film cameras. It lifted off from Pad 34 at 17:15:32 GMT on 25 August 1966. A key objective was to verify the emergency detection system in closed-loop configuration. At cutoff, the S-IVB was at an altitude of 120 nautical miles and climbing on a ballistic arc. Eleven seconds after separating, the spacecraft fired its service propulsion system in order to place itself on a higher trajectory that would result in entry over the Pacific. As a thermal test, the spacecraft then turned to aim its apex towards the Earth and maintained this attitude through the peak altitude of 618 nautical miles above Africa. On descending over the Indian Ocean it realigned its apex to the velocity vector, then fired its main engine for 89.2 seconds to accelerate for atmospheric entry and concluded by firing it briefly twice more in rapid succession as a demonstration of rapid restart.

In contrast to the ‘rolling’ entry made by AS-201, this time the command module controlled its attitude to fly a trajectory that ‘skipped’ off the atmosphere to trace a ballistic arc which led to a second contact and full entry. A similar profile was to be used on returning from the Moon. The double peak in the heating rate was designed to expose the shield to low heat rates with high heat loads – lower temperatures, but applied for longer – than a ‘straight in’ lunar return. Although the temperature at the base of the shield peaked at 1,482°C, the cabin did not exceed 21 °C. After a flight of 93 minutes, the command module splashed into the Pacific and adopted the apex-up flotation attitude. But the flight path angle at entry of-3.53 degrees was steeper than the desired -3.48 degrees and the lift-to-drag ratio of 0.28 ( + 0.02) was less than the predicted 0.33 ( + 0.04), causing it to fall short by 205 nautical miles. It was 8 hours before USS Hornet recovered the capsule. The planners would have to take into account the lower than expected lift-to-drag ratio of the command module. This qualified the heat shield for Earth orbital missions, but additional tests would be required for a lunar return. Both the Saturn IB and the Block I spacecraft were declared ready for the first manned mission.

As 80 per cent of the objectives specified for CSM-002, CSM-009 and CSM-011 had (between them) been met, AS-204 was released for the manned Apollo 1.

THE SURFACE MATERIAL

As William Herschel was passing sunlight through a prism in 1800, he found that heat was refracted just beyond the red end of the visible spectrum, so he named this infrared radiation. The Estonian physicist Thomas Johann Seebeck discovered in 1821 that if two wires of different metal are made into a loop by soldering their ends together, then an electric current will flow if the joins are at different temperatures. In 1856 Charles Piazzi Smyth utilised such a thermocouple to detect solar infrared reflecting off the Moon. Laurence Parsons inherited the 72-inch reflecting telescope built by his father at Birr Castle in Ireland. ft was the largest telescope in the world at that time. The common view was that since the airless lunar surface was exposed to the intense cold of space, it simply must be covered by ice. fn fact, S. Ericsson of Norway had proposed in 1869 that the lunar landscape was shaped by glaciation. fn 1870 Parsons equipped his telescope with a thermocouple and found that at lunar noon the temperature of the equatorial zone – where the Sun would pass close to the zenith – exceeded that of the boiling point of water, which indicated that the surface could not be ice. Measurements of the angle of polarisation of the surface published by M. Landerum in 1890 confirmed that it could not be ice. Despite the measured high temperatures at lunar noon, P. J.H. Fauth in Germany endorsed the idea that the landscape was shaped by glaciation, and in 1913 he and Hans Horbiger announced the highly unorthodox theory that ice was the essence of the cosmos! However, the vapour pressure of ice would cause it to sublime in the vacuum. ff ice were indeed present, it would have to be subterranean. fn 1916 Pierre Puiseux in Paris pointed out that if ice were present in the amounts claimed by Fauth, then it should be most evident at high latitudes where the Sun did not rise far above the horizon – yet there were no polar caps. Nevertheless, W. H. Pickering speculated that there might be ice at the summits of lunar peaks. The outcome of these studies was therefore that the majority of the surface was not ice.

fn 1930 Edison Pettit and Seth B. Nicholson put a thermocouple on the 100-inch reflector on Mount Wilson, which at that time was the largest telescope in the world, and discovered that the surface temperature in the equatorial zone varied by several hundred degrees during the monthly cycle. At the onset of a lunar eclipse in 1939 they measured the temperature plunge by 120°C in the space of an hour as the Moon entered the Earth’s shadow. This implied that the material on the surface was poor at retaining heat. On making more sophisticated measurements, they found that at the equator the temperature was +101°C at noon, fell to -39°C at sunset and -160°C at midnight. fn 1948 A. J. Wesselink in Holland inferred from these cooling rates that the Moon could not be exposed solid rock but must be covered by a blanket of loose material.

After the Second World War, the Moon was investigated at radio wavelengths. fn 1946 Robert H. Dicke and Robert Beringer in America detected thermal emission from the Moon at a microwave wavelength of 1.25 cm. Using the same wavelength, in 1949 J. H. Piddington and H. C. Minnett in Australia measured the temperature of the whole disk at a variety of phases over three lunations. The variation proved to be less extreme than it was at infrared wavelengths. The fact that the radio temperature lagged behind the optical phase of the Moon by 3.5 days suggested the presence of a thin insulating layer with low thermal conductivity. fn 1950 John Conrad Jaeger in Australia matched materials to the microwave observations made by Piddington and Minnett. Agreeing with Wesselink’s inference of loose material, Jaeger argued for a layer of ‘dust’, typically only several millimetres thick, resting on top of a granular material. Observations of lunar eclipses on 29 January 1953 and 18 January 1954 at microwave wavelengths by the US Naval Research Laboratory implied that only the uppermost part of the surface underwent a large variation in temperature. This was consistent with a thin layer of dust on a loose granular material. In 1962 J. F. Denisse in France announced that for wavelengths exceeding 30 cm there was no variation in temperature over the monthly cycle.

Taken together, these investigations indicated that whereas an optical telescope fitted with a thermocouple measured the temperature of the surface itself, the radio temperatures were averages for granular material to depths corresponding to several times the wavelength. The constancy at wavelengths greater than 30 cm implied that the material in the uppermost metre or so was such a poor conductor of heat that even when the Sun was at the zenith its heat did not penetrate that far. And at night, although the surface rapidly radiated away the heat it had gained during the day, the poor conductivity of the deeper material served to insulate it. The temperature at a depth of about one metre was estimated to be a constant -40°C. Candidates for the uppermost metre of material were a porous volcanic rock like pumice or a granular conglomerate. A colloquium held in Dallas, Texas, in 1959 concluded that the fine dust that formed the actual surface was probably of meteoritic origin. It was initially believed that the Moon is particularly bright at its ‘full’ phase due to there being no shadows in view – the objects at the centre of the disk cast no shadows, and objects away from the centre mask their shadows to terrestrial observers. But the absence of appreciable darkening of the limb proved to be a result of the fact that the surface ‘scatters’ more light back towards its source than it does in other directions. It was inferred from this that the material at the surface was a porous vacuum-sintered dust, and that sunlight which penetrated a ‘cavity’ was not absorbed but reflected back out towards its source.

In 1955 Thomas Gold, an astronomer with a wide-ranging interest who was then at the Royal Greenwich Observatory in England, proposed that particles of dust on the lunar surface would become electrically charged by the harsh ionising ultraviolet radiation from the Sun, and that in making the grains of dust repel each other this would cause them to flow remorselessly ‘down hill’ and collect in low-lying areas. Tests using powdered cement in a vacuum had shown that this tended to form fragile ‘fairy castle’ structures full of voids, which was consistent with the inference that the surface material was porous. Gold claimed that the maria were accumulations of dust, possibly several kilometres thick, and were of low albedo because the dust had been darkened through exposure to radiation. But whilst dust moving down hill could bury craters in low-lying terrain, it could not explain the missing ‘seaward’ wall of a crater such as Le Monnier on the margin of Mare Serenitatis, nor the dark floors of Archimedes sitting on elevated terrain or Plato embedded in the lunar Alps.

A. Deutsch in Leningrad suggested in 1961 that there might be life in the granular material where the temperature was constant, and that it lived off gases leaking from the interior. Expanding on this, Carl Sagan in America speculated that if the granular material were tens of metres deep, then it might contain a considerable amount of ice and organic material.

As the space age dawned, therefore, there were already interesting insights and speculations into the nature of the lunar surface material.