Orwell Astronomical Society (Ipswich)
The Apollo Programme
In December 1968, mankind passed a landmark in exploration when the first men travelled to the Moon and returned safely. The three-man crew of Apollo 8, Frank Borman, Jim Lovell and Bill Anders, blasted off to test the Command and Service Module (CSM) by orbiting the Moon. I had played an extremely minor part in the endeavour for, in the late 1960s, I was an Apprentice Instrument Maker, indentured at Marconi Elliott Flight Automations in Basildon, Essex. The firm, originally part of the Marconi Company, had been taken over by the American firm Elliotts, who were sub-contracted by Grumann, principle contractor for the Lunar Excursion Module (LEM) to provide on-board navigation systems. It was the privilege of my colleagues, in the most sterile of workshops and under intense security, to manufacture some of the switching panels for the LEM. I had the great fortune to be in the appropriate workshop at the time and to assist with the panels as part of my training. By coincidence, in 1972 Elliotts sold the company back to Marconi, the Apollo programme was cancelled after Apollo 17 (December 1972), and I left engineering in pursuit of an entirely different career.
This article provides a retrospective on the Apollo missions leading up to the immortal One small step phrase of Neil Armstrong in July 1969. We should begin with a reminder of the events that brought NASA to undertake this monumental endeavour.
A cynic might claim that the Moon landings were born entirely of a desire by America to best the Soviet Union and win a kind of moral or scientific/engineering victory. I believe that while there is substance to that opinion, it isn't the whole story and the ordinary men and women of NASA were made of better stuff than that. However, in 1957, at the height of the cold war, the western world was stunned when the USSR successfully put Sputnik One into orbit - its "bleep, bleep, bleep..." message galvanised public opinion to a view that the "Reds" shouldn't have space for themselves. Another landmark event compounded the matter when, in April 1961, Yuri Gagarin became the first human to enter outer space and orbit the Earth. Despite constantly trailing Soviet space feats, NASA managed just one month later to successfully launch astronaut Alan Shepherd into a sub orbital space flight and a few days afterwards the "space race" really began when President J F Kennedy threw down the following challenge to the American nation:
I believe 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 Earth. 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.
Gradually, via the one-man Mercury and two-man Gemini space vehicles, NASA achieved many technological and manned space flight firsts, seizing the initiative from the USSR. Also during this period, NASA sent unmanned Ranger probes on photographic missions to the Moon, transmitting an abundance of pictures to Earth before crashing onto the surface. NASA followed these with the Surveyor probes which soft landed on the surface, supplying much needed data on its composition and thousands of high resolution photographs.
All faith was pinned on NASA's long-planned manned lunar exploration programme - Project Apollo. The Apollo programme was to utilise a three-man capsule, capable of sustaining the astronauts in its CSM with a separate LEM comprising landing and ascent vehicles for the Moon landings themselves. NASA had developed a new launch vehicle for Project Apollo - the mighty Saturn V rocket. The scale of the Saturn V can be appreciated at the Kennedy Space Centre where the rocket for the cancelled Apollo 18 mission, together with much other space paraphernalia, is on display - see figures 1-4 below by James Appleton, 1993. Figure 5 is a scale drawing of the Saturn V.
Fig. 5. The Saturn V.
Apollo 1 was ready at the start of 1967 atop its Saturn 1 rocket at Cape Canaveral. The Apollo capsule was not without critics of poor standards of workmanship and a general haste in manufacture and, unfortunately, their worst fears were realised on 27 January when the three-man crew, Gus Grissom, Ed White and Roger Chaffee, were going through a full dress rehearsal for launch. A spark ignited the pure oxygen environment inside the capsule, killing all three. The nation, indeed the world, was stunned by the tragedy and, as a result, NASA redesigned virtually the whole capsule and replaced the pure oxygen environment with a nitrogen/oxygen mixture. Meanwhile, the next five Apollo missions would be unmanned until all problems were ironed out of the systems.
Apollo 2 successfully launched in July 1967 to test the Saturn 1B booster system.
Apollo 3 launched in August 1967 to test the systems on the CSM along with the heat shield.
Apollo 4 launched in November 1967. This was the first time that the launch used the 363 ft tall Saturn V booster. The mission lasted over eight hours and included two Earth orbits by the CSM to test re-entry systems.
Apollo 5 launched in January 1968, atop a Saturn 1B booster to test, for the first time, an unmanned LEM.
Apollo 6 launched in April 1968 for a test of the Saturn V booster and the CSM. The Saturn V suffered a number of faults - ignition failures on the second and third stages and an oscillation in the rocket's flight attitude.
Apollo 7 marked the first successful manned flight of Project Apollo when, in October 1968, astronauts Wally Schirra, Donn Eisele and Walt Cunningham orbited Earth in the CSM. The mission lasted eleven days and various minor faults manifested themselves and were easily resolved - however, things were not helped by the crew who suffered from heavy colds and became increasingly irritable as they were instructed by Mission Control at Houston, Texas, to undertake various tests which they considered trivial and of little practical importance. In fact, the three astronauts "blotted their copybooks" and none were ever to return to space. Overall, however, the mission paved the way for the boldest leap yet.
Apollo 8 was originally to have been a manned proving mission to Earth orbit to test the LEM. However, the technical success of Apollo 7 and fears over the Soviets' new Zond spacecraft, which had recently safely completed unmanned return flights to the Moon, spurred NASA to bring forward a manned lunar orbital flight from Apollo 9. At 7.51am on 21 December 1969, Borman, Lovell and Anders blasted off atop a Saturn V from Launch Pad 39A at Cape Kennedy with just a CSM (no LEM). After two hours and 50 minutes of orbital flight, mission control gave the go-ahead for Trans-Lunar Injection (TLI) and a burn of just over five minutes of the third stage of the Saturn V raised the ship's speed to 24,226 mph, sending Apollo 8 away from Earth. For the first time, mankind witnessed Earth as a celestial body hanging in the void of space.
At a distance of 38,900 miles from the Moon, Apollo 8 slowed to 2,223 mph. Lunar gravity began to exert itself increasingly on the ship and, some 69 hours into the mission, the CSM reached the Moon, at this time travelling at a speed of 5000 mph. It swung around the far side on Christmas Eve and a 242 second burn of the Service Propulsion System (SPS), plus some further short burns for adjustment, placed it in an almost circular lunar orbit at an altitude of 60 miles. After the frenetic activity associated with entering lunar orbit had subsided, when asked by the mission control room what the Moon looked like, Jim Lovell's voice came back:
Essentially grey, no colour, like plaster of Paris or a sort of greyish beach sand.
Descriptions from Borman and Anders included:
It looks like a vast, lonely, forbidding place, an expanse of nothing - clouds of pumice stone.
You can see the Moon has been bombarded through the aeons with numerous meteorites. Every square inch is pockmarked.
Lunar orbit lasted for 20 hours and 11 minutes, during which time the astronauts undertook a hefty schedule of photographic work over five potential landing sites that NASA had identifed. One photograph taken during their orbit has become a true icon of the space age: Earthrise, showing our planet at about two-thirds phase at a distance of 240,000 miles, 5° above the lunar horizon, itself approximately 430 miles from the spacecraft (see figure 6). In a famous TV transmission from lunar orbit on Christmas Day 1968, the crew quoted passages from the Book of Genesis, In the beginning God created the heaven and the Earth, and closed with seasonal greetings to all people back on the good Earth.
The SPS executed a 203 second burn on the far side of the Moon to propel the capsule back towards home. The chilling prospect of a malfunction leaving the astronauts trapped in eternal lunar orbit was happily unrealised and the world knew that all was well when Lovell's voice came on the radio saying: Please be informed there is a Santa Claus. On the sixth day of the mission, a 363 ft high rocket had been reduced to just a 12 ft capsule, which plunged into Earth's atmosphere at 24,700 mph towards a splashdown four miles away from the aircraft carrier USS Yorktown in the Pacific Ocean and a world-wide welcome as heroes.
The mission had covered a total distance of 6,000,000 miles at a cost of $310,000,000; just two more test flights stood before the momentous first manned lunar landing.
Apollo 9 represented NASA's next step towards reaching the Moon. It launched from Cape Canaveral on 03 March 1969, with astronauts James McDivitt, Dave Scott and "Rusty" Schweickart aboard. Their mission goal was to test the integrity of the whole Apollo system and, for the first time, fly the LEM with a crew on board and practice separation, rendezvous and docking procedures. Their journey would involve a ten day flight and 151 Earth orbits over a distance of some 4,350,000 miles.
When orbital height had been achieved, the Command Module pilot, Dave Scott, began a critical manoeuvre by separating the CSM from the last stage of the Saturn V rocket and turning it around to extract the LEM from its adapter and casing at the top of the 3rd stage. This essential manoeuvre was known as transposition and docking. After the manoeuvre, the final stage of the Saturn V rocket fired its engine and sped away from Earth into solar orbit. The crew spent the following 24 hours checking systems on the docked spaceships and resting. Schweickart had been designated LEM Pilot. ("Pilot" was a loose term as the mission commanders actually flew the LEM whilst the "pilot" who, by NASA convention, was the least experienced astronaut, acted as systems engineer). It was Schweickart's task to test the integrity of the space suits that astronauts would wear on the surface of the Moon by an extra vehicular activity (EVA) or spacewalk, climbing outside the LEM, standing on the steps and retrieving various experimental samples from the side of the craft. However, NASA had to delay this part of the mission by four days as Schweickart was suffering from spacesickness.
On day five, the most critical part of the mission began when McDivitt and Schweickart entered the LEM and separated the craft from the CSM. At this point, the LEM (known by the nickname Spider) became mankind's first true spaceship by virtue of having been built entirely for use in space and having no terrestrial integrity. After an initial period flying around the Command Module (nicknamed Gumdrop), McDivitt fired Spider's descent engine and drew the craft 13 miles above Gumdrop; after two hours he increased the distance to 50 miles. The two craft later drifted back towards each other before McDivitt fired the engine again to simulate an actual lunar descent.
At a distance between the two craft of 100 miles, McDivitt fired explosive bolts to separate and jettison the descent stage of Spider. He then fired the ascent stage engine to bring the ascent stage of Spider back to dock with Gumdrop. NASA had planned for the LEM pilot to perform the redocking manoeuvre but, after McDivitt experienced great difficulty stabilising the ascent stage, it was decided that all future dockings would be undertaken by the Command Module pilot who had the advantage of a heavier and consequently more stable craft. When the crew had transferred back into the Command Module, Spider was jettisoned to burn up in Earth's atmosphere as the descent stage had done earlier.
The crew spent the next few days performing various experiments including the use of a revolutionary Earth resources camera (environmental matters were beginning to come to prominence in those days). NASA delayed splashdown by one orbit due to high seas in the Pacific and used the mission's alternative splashdown point in the Atlantic, with recovery by the USS Guadalcanal, 535 miles south of Bermuda. The mission had been almost faultless.
Apollo 10 was the final stepping stone before a manned Moon landing. Lift-off was at 12.49pm on 18 May 1969. The mission extended for eight days and involved orbiting the Moon whilst the LEM crew tested out the ship in a full dress rehearsal of landing and redocking. The crew consisted of Col. Tom Stafford (Commander), Cdr. John Young (Command Module Pilot) and Cdr. Eugene Cernan (LEM Pilot). The Command Module and LEM were nicknamed Charlie Brown and Snoopy respectively. The crew inevitably experienced a slight sense of "what might have been" because Apollo 10 was originally conceived to be the first landing mission; however, the chain of events described above conspired against that plan and left Apollo 10 with an LEM not completely equipped for such a landing owing to difficulties with production schedules.
A great deal of publicity surrounded the mission and no less than 19 TV shows were transmitted during the flight. The transmissions often extended beyond schedule and were light hearted and clearly intended to show the average American what all the tax dollars were buying! After a relatively routine journey, Apollo 10 entered lunar orbit on 21 May and, following 11 full orbits, Stafford and Cernan entered Snoopy and separated from Charlie Brown. Some months earlier, NASA had determined that Mare Tranquillitatus offered the best chance of a smooth site for the first landing and Apollo 10 was targeted to overfly the site, whilst practising and perfecting the navigation techniques that the crew of the next mission would need to use. Snoopy's descent engine was burned for 27 seconds, which allowed it to drop to just 50,000 ft above the lunar surface and, as the craft swept in low over Mare Tranquillitatus, Stafford said: There's enough boulders here to fill up Galveston Bay! On seeing the proposed landing site he described it as having a number of holes, but looking mostly smooth like a very wet clay - apart from the larger craters. (Subsequent analysis of the flight showed that the crew was some four miles south of the landing point at that moment. Identification of the error proved useful in final course corrections for the next mission.)
Stafford fired the explosive bolts holding the descent stage and, moments before the ascent stage engine was to be fired, Snoopy went into a violent spin for around eight seconds until Stafford could bring the craft back under control. Cernan obviously thought that they were going to crash, his voice tapes indicating so in no uncertain manner. (The culprit was an incorrectly set abort switch, which caused Snoopy to begin a programmed automatic return to Charlie Brown, whilst in a dangerous downward attitude towards the surface). A successful burn returned Snoopy to re-docking with Charlie Brown and, after a total of 31 orbits, Apollo 10 burned the SPS engine for a homeward flight. After an 830,000 mile journey, the Command Module splashed down just three miles from USS Princetown. So near and yet so far for the crew, the mission had been a huge success and nothing now stood in the way of a landing by Apollo 11 in two months time.
Apollo 11 launched at 9.32am local time on 16 July 1969. The colossal form of a 363 ft high Saturn V rocket, powered by an unimaginable 7,650,000 lbs of thrust created an awesome noise and slowly rose from launch pad 39A at Cape Kennedy. The spectacle will remain permanently etched in the memories of 1,000,000 plus spectators around Cape Kennedy (including countless invited VIPs and a 3,000 strong press corps) and many of the estimated 600,000,000 TV viewers world-wide. Sitting atop this colossus and carrying the prayers of the world with them were civilian Neil Armstrong (Commander), Lt-Col. Michael Collins (Command Module Pilot) and Col. Edwin Buzz Aldrin (LEM Pilot). The mission had begun.
Apart from TV broadcasts, the outward trip was almost routine as the Command Module (Columbia) and LEM (Eagle) flew at speeds up to 24,550 mph towards the Moon; on arrival, a 357 second burn of the SPS placed the craft in lunar orbit on 19 July. There followed a period of system checks prior to separation of the two craft. On that first day of orbit, the crew reported that the north walls of the crater Aristarchus, long suspected to be volcanically active, exhibited a luminosity in the view through their binoculars. Ground based observers simultaneously and independently confirmed this as a Transient Lunar Phenomena (TLP) .
At 100 hours into the mission, Armstrong fired the descent engine on Eagle for 30 seconds to begin the approach towards the target landing area on Mare Tranquillitatus. At an altitude of 9.1 miles, a further 756 second burn began for final approach. All went well until Eagle reached an altitude of 47,000 ft when a series of programme alarms began to sound. The on-board computer could not handle the flow of information being fed into it; Steve Bales, flight engineer in charge of computer systems at mission control, surmised what was taking place and made the brave decision not to call an abort. At 1,400 ft Armstrong realised that the auto navigation systems were leading Eagle to a landing on unsuitable rough ground, strewn with large boulders and a crater. He immediately switched to manual control, and began to direct the flight of the LEM by a joystick similar in operation to that of a helicopter (tilt forward to move forward, and so forth) facilitating responsive manual control of its trajectory. He began, with Aldrin, to look for smoother ground; the search was aided by shrewd timing of the mission: NASA scheduled the lunar landings so that the Sun would be low on the horizon and behind the LEM; on the monotone lunar surface the long shadows assisted the pilots to spot boulders and craters as well as giving an indication of surface relief beyond that which the ship's instruments indicated. Within a few moments, Charlie Duke (Capsule Communicator - CAPCOM - at Houston) told the crew they had just 60 seconds of fuel remaining. That was expected, although the crew had hoped to be on the ground before then. When Duke told them that they were down to 30 seconds - it was definitely time to land! Perhaps it would be best to quote from the voice recordings at this point:
Eagle: Drifting to the right a little. Contact light. OK, engine stop.
Houston: We copy you down Eagle.
Eagle: Houston, Tranquillity Base here. The Eagle has landed.
Houston: Roger Tranquillity, we copy you on the ground. You've got a whole bunch of guys about to turn blue. We're breathing again!
The time was 21:18 BST on 20 July 1969. The landing site, some four miles further on than planned, is at co-ordinates 0.67°N, 23.5°E, roughly one-third of the way between the craters Sabine/Ritter and Maskelyne, displaced a little south towards the crater Moltke. Figure 7 shows the location of the landing site superimposed on a photograph of Mare Tranquillitatus . The region is easily visible with amateur equipment and figure 8 shows a photograph taken on 23 July 1999, just after the thirtieth anniversary of Armstrong's one small step. (By James Appleton, 250 mm SCT at prime focus, 1/15th sec exposure on 50 ASA B&W print film.)
An intense period of status checks followed. Some years after the landing, Buzz Aldrin recalled that he was so busy inside the LEM that he didn't have time to look out of his window and that was his one regret on the mission. Having donned their life support packs and EVA suits (designed to sustain the astronauts on the surface in full solar radiation and extremes of temperature from +240°F in sunlight down to -279°F in shaded areas), it was time for the supreme moment of the mission and, perhaps, of all space exploration. Armstrong crawled out of the tiny hatch and down the ladder into the field of view of a crude black and white TV camera, relaying the image to countless millions around the globe. The last rung of the LEM ladder was some three feet above the footpad and Armstrong had to jump. Back to the voice tape:
I'm at the foot of the ladder now.
The Lunar Module footpads are only depressed in the surface about one or two inches although the surface appears to be very fine grained as you get close to it, its almost like a powder. Now and then it's very fine.
I'm going to step off the Lunar Module now.
That's one small step for man. One giant leap for mankind.
It was 03.59 BST on 21 July 1969. First things first, Armstrong scooped up a small amount of surface dust and placed it in a special pocket on his spacesuit in case any unforeseen problems might lead to an early abort of the mission - at least they wouldn't go home empty handed. After a short while it was Aldrin's turn to join Armstrong in the EVA. Stepping onto the surface he uttered two words that seem to have encapsulated all the descriptions given by all the astronauts to follow him: magnificent desolation.
Walking on the lunar surface in one sixth of Earth's gravity and wearing a suit with a combined total weight of 300 lbs (equalling 50 lbs on Earth) took some getting used to! The favoured method of walking was to spring/twist from the ankles, which gave the astronauts a curious loping, hopping gait so familiar from the film archive. Alan Bean (LEM pilot on Apollo 12) was later to say that he felt immensely strong - almost as though he were an Olympic athlete. Armstrong went no further from the LEM than just 100 yards; more extensive journeys on the surface would follow on later missions. Much time was spent erecting the Stars & Stripes and unveiling a plaque on one leg of the descent stage which bore the inscription: Here men from the planet Earth first set foot upon the Moon July 1969 AD. We came in peace for all mankind. The plaque bore the signatures of the three-man crew and President Nixon. The astronauts placed other mementos around the landing site, including messages from world leaders and memorials to astronauts and cosmonauts who had died in exploration. Notable amongst these items, but totally unofficial, was an astronaut's diamond-set gold pin badge which the wives of the Apollo 1 crew presented to Deke Slayton (NASA's Chief of Flight Operations) after the death of their husbands. President Nixon took time off from answering awkward questions raised by reporters on the Washington Post to make an embarrassing telephone call to Armstrong and Aldrin, which he milked for all its historic, political worth. However, it wasn't all ceremony and the astronauts placed experimental equipment upon the lunar surface to measure the solar wind, a seismograph to monitor "moonquakes" and meteor impacts and a laser reflector to facilitate accurate measurement of the Earth-Moon distance. The astronauts also took several core samples, bringing the earthbound rock collection to approximately 48 pounds in weight.
After 134 minutes, it was time for Armstrong and Aldrin  to return to the Eagle. Once inside they had a five hour sleep (as if anyone could sleep in the circumstances!) in the cold and somewhat austere ascent stage. It was time for one of the most nail-biting aspects of the whole mission: would the ascent stage engine fire or would the astronauts be marooned for eternity on the surface? All went well and a 435 second burn of the ascent engine took them back to lunar orbit and eventual rendezvous with Mike Collins in Columbia. Mike had spent his lonely time photographing the lunar surface. During a press conference before lift-off he had caused much laughter by asking the media to hang onto all the TV recordings so that he could see what had taken place - the supreme irony being that he was one of the very few people who couldn't see Armstrong and Aldrin on the lunar surface live!
Following a flawless redocking and transfer of crew and samples, Eagle's ascent stage was jettisoned to crash onto the lunar surface (helping to confirm that the seismograph left at Tranquillity Base was functioning). Having made 30 orbits of the Moon over almost 60 hours, the SPS on Columbia burned for 149 seconds on the far side to propel Apollo 11 homewards. The trip home was notable for a TV transmission in which the crew told millions of viewers around the globe of their feeling of elation - and how grateful they were to everybody who had contributed to the Apollo project. (The transmission engendered a sense of pride in we workers at Marconi's who had played our small part in the project.) Eight days after its awe-inspiring lift-off, what remained of the mighty Apollo 11 spacecraft splashed down in the Pacific Ocean near Johnson Island, some 13 miles from the waiting carrier USS Hornet. The President was on board ship to greet the astronauts before they were sealed in a special chamber for a three week period in case of any bacterial contamination on the Moon, fears of which were happily unfounded. The late President Kennedy's target of putting a man on the Moon and returning him safely to Earth before the end of the decade had been brilliantly achieved.
Next time you observe the Moon, why not take the time to observe Mare Tranquillitatus around the craters Maskelyne, Sabine and Ritter and ponder the momentous events which took place there in 1969?
A term first coined by Patrick Moore to cover reported observations of pinpoint flashes or colour variations on the lunar surface. The possible causes are subject of much speculation: meteor strikes or volcanic activity.
From "The Hatfield Photographic Lunar Atlas", Jeremy Cook, Springer-Verlag, 1999.
Aldrin's EVA lasted for one hour and 44 minutes.
Ken Goward, FRAS