THE END

As the Gemini XII flight hardware – Lovell and Aldrin’s spacecraft home, their Titan booster, their Atlas-Agena – was readied for launch during 1966, it was accompanied by an impending deadline to terminate the project and press on with Apollo. Indeed, when the two men walked out to Pad 19 on launch morning, 11 November, they would wear placards reading ‘The’ and ‘End’ on their backs. By this point, the corroded dome of the second-stage fuel tank previously assigned to Gemini X had been repaired and was delivered from Martin’s Denver to Baltimore plants in late January. Seven months later, on 12 August, the entire Titan for Gemini XII was approved by Martin and by mid-September both of its stages were at Cape Kennedy.

It was at around this time that the Air Force’s AMU test was deleted from Gemini XII and Gene Cernan lost his final opportunity to test-fly it in orbit. Persistent problems with mastering EVA techniques on previous missions had, NASA management concluded, made it inadvisable to proceed with such an ambitious endeavour and Gemini XII would instead focus on perfecting the ‘fundamentals’ with just basic extravehicular tasks. During his time outside, Aldrin would remove, install and tighten bolts with the power tool whose evaluation had been denied both Dave Scott and Dick Gordon, as well as operating connectors and hooks, stripping patches of Velcro and cutting cables.

To physically condition themselves, Aldrin and Cernan spent a considerable amount of time underwater in the neutral buoyancy tank, just outside Baltimore. They wore carefully-ballasted suits, Aldrin said later, to completely neutralise their buoyancy and approximate microgravity conditions as closely as possible. “Eventually,” he wrote, “I mastered the intricate ballet of weightlessness. Your body simply had to be anchored, because if it wasn’t, flexing your pinkie would send you ass-over-teakettle. And you don’t want to do that dangling at the end of an umbilical cord 160 miles above Earth.’’

Processing of the Atlas booster and Gemini’s final Agena target ran in tandem with that of the Titan. Designated Agena ‘5001’, it was actually the non-flying version of the target delivered to Cape Kennedy in the summer of 1965, which had since been upgraded and made space-capable. ‘‘Getting a docking target took a bit of juggling,’’ wrote Deke Slayton. The Air Force formally accepted it for advanced processing early in September 1966 and by the end of October it had been mated atop its Atlas and installed on Pad 14. For Lovell and Aldrin, their scheduled launch just a few days after Halloween had spawned an interesting orange-and-black embroidered crew patch, together with a crescent Moon offering a nod to the impending Apollo project.

Plans to launch on 9 November were abandoned when a malfunctioning power supply in the Titan’s secondary autopilot reared its head and Lovell and Aldrin were recycled to fly two days later. The morning of the 11th dawned fine and clear and the Agena set off promptly that afternoon at 2:08 pm. (During insertion into space, an anomaly was noted in the target’s propulsion system and plans to boost Gemini XII into a higher orbit were abandoned.) Strapped inside their tiny cabin, both astronauts could clearly hear the Atlas’ thunderous roar. Ninety-eight minutes later, at 3:46:33 pm, it was their turn.

‘‘There was no noise at first,’’ Aldrin wrote, ‘‘but then a growing rumble began as the spacecraft rolled through its pre-programmed manoeuvre, twisting to the proper south-east launch trajectory.’’ Steadily, the Titan accelerated, ‘‘like a subway train’’, Aldrin recalled, and as they climbed ever higher the sky turned to dark blue and eventually to black. Inside their space suits, both men felt their limbs rise and their toes lift to touch the tops of their boots. It felt almost as if they were stretching their feet, but not quite. They were weightless.

Once established in their 160 x 270 km orbit, Lovell and Aldrin set to work ploughing through their checklists, preparing for rendezvous and docking with the Agena some three orbits – and a little over four hours – into the mission. At around 5:11 pm, they made their first attempt at radar contact with the target and were surprised when the computer responded with the desired digits. ‘‘Houston,’’ radioed a jubilant Aldrin, ‘‘be advised we have a solid lock-on … two hundred thirty-five point fifty nautical miles.’’

However, the astronauts’ success proved short-lived. As they circularised their

Jim Lovell (left) and Buzz Aldrin at breakfast on launch morning.

orbit to align themselves ‘behind’ and ‘below’ the Agena, above North America, Gemini XII’s radar began giving intermittent readings. It was at this stage that Aldrin’s years of rendezvous work came to the fore: he broke out the intricate charts and reverted to what he called the ‘Mark One Cranium Computer’ – the human brain. In his autobiography ‘Men from Earth’, Aldrin vividly described the hours – long effort: as Lovell piloted Gemini XII, he laboured over the charts, barely able to see the closely-printed data, occasionally aware of the passage of orbital daytime into nighttime and vice-versa.

It paid off. A little over four hours into the mission, Lovell eased the spacecraft’s nose into the Agena’s docking collar and announced, somewhat nonchalantly, ‘‘Houston, we are docked’’. The response from the ground, delivered with similar excitement, was a simple ‘‘Roger’’. A potentially serious obstacle – the failure of a critical piece of equipment, the rendezvous radar – had been overcome by human brainpower and flying abilities. Should a similar contingency occur during a rendezvous situation in orbit around the Moon, Lovell and Aldrin’s work had at least proved that workarounds could be achieved. They had also used barely 127 kg of their fuel supply in one of the project’s most economical rendezvous.

For the fourth time in eight months, a Gemini was securely linked to an Agena and Lovell and Aldrin became the second crew to practice undocking and redocking exercises. One attempt by Lovell during orbital darkness caused the docking latches to ‘hang up’ – producing a rather disturbing grinding sound – but he was nevertheless able to rock Gemini XII free without damage. A few minutes later, they switched roles and Aldrin redocked them onto the target.

Original plans, laid out before launch, had called for a reboost to high altitude, but this had to be abandoned eight minutes after the Agena lifted-off when its engine suffered a momentary decay in thrust chamber pressures and a drop in turbine speed. Instead, the astronauts were directed to turn their attention to solar eclipse photography; this task had been a scheduled part of their mission had they launched on 9 November, but the two-day delay caused it to be dropped. Now that the Agena reboost had been cancelled, it was reinstated, thanks to the input of Gemini XII’s experiments advisory officer James Bates.

The inclusion of Bates’ recommendation marked a shift in operations, with the scientists’ representative, for the first time, being allowed to participate as one of the flight control team in the main Mission Control room. Moreover, it was determined that the Agena’s secondary propulsion system had enough power to orient the spacecraft for an eight-second photographic pass at the proper time. At 10:51 pm, a little over seven hours into the mission, Lovell duly fired the target’s smaller engines to reduce the combination’s speed by 13 m/sec. The adjustment was successful and, after their first sleep period, the astronauts were advised to perform a second firing. Sixteen hours after launch, they reported seeing the eclipse ‘‘right on the money’’, cutting a swath across South America from north of Lima down to the southernmost tip of Brazil.

At first, it had seemed to the disgruntled crew that the second Agena burn might throw out the remainder of their schedule and adversely affect the start of Aldrin’s first EVA. It did not, and at 11:15 am on 12 November, some 20 minutes before orbital sunset, Aldrin cranked open his hatch and pushed his helmeted head outside. “The hatch rose easily,” he wrote, “and I rose with it, floating above my seat, secured to the spacecraft by short oxygen inflow and outflow umbilical hoses.” Years later, he would vividly describe the immensity of the Universe all around him, remember the absence of any sense of speed and the recall the distinct curvature of Earth.

Aldrin quickly set to work on his first task, dumping a small bag containing used food pouches, and watched it slowly tumble away like a top, straight ‘above’ him. Next he moved on to quickly attach cameras onto brackets to photograph star fields on ultraviolet film and retrieved a micrometeoroid package, which he passed inside to Lovell. Unlike Cernan and Gordon, he did not overheat, thanks partly to regularly-scheduled rest breaks of two minutes apiece, and he returned inside Gemini XII at 1:44 pm after two and a half hours.

His real work had yet to begin. The mission’s second period of EVA, which got underway at 10:34 am the following morning, required Aldrin to move away from the spacecraft on a 9 m tether. He set up a movie camera to allow flight controllers to monitor his performance, then moved to Gemini XII’s nose and affixed a waist restraint strap to the docking adaptor. Next, Aldrin removed a tether from the Agena’s nose and snapped it onto the Gemini, connecting the two vehicles for a gravity gradient exercise scheduled for later in the mission. He then manoeuvred himself towards the rear of the spacecraft, using flatiron-shaped handholds fitted with Velcro patches, and slipped his boots into a pair of foot restraints nicknamed ‘golden slippers’. These, coupled with two small waist tethers, kept him anchored securely and Aldrin was able to satisfactorily complete a number of tool-handling and dexterity tests.

‘‘Back in the buoyancy pool in Maryland,’’ he wrote later, ‘‘I had torqued bolts and cut metal dozens of times – what I used to call ‘chimpanzee work’ – and I had no problem with these chores in space. Someone even put a bright yellow paper Chiquita Banana sticker at my busy box.’’ He was even able to wipe Lovell’s window (who asked him to change the oil, too) before returning to the cabin after two hours and six minutes outside. Back on Earth, Aldrin would claim quite openly that he had personally solved many of the problems of EVA, arousing criticism among the other astronauts, including Gene Cernan, who felt that his tasks were nowhere near as difficult as theirs. ‘‘Quite frankly,’’ Cernan wrote, ‘‘we said he was only working a monkey board. Draw your own conclusions.”

Shortly after Aldrin’s return inside Gemini XII, the two men completed their evaluation of the tether by undocking from the Agena. The tether tended to remain slack, although they believed that slow gravity gradient stabilisation was achieved. ‘‘Within minutes,’’ wrote Aldrin, ‘‘the two vehicles had stabilised without the aid of thrusters.’’ After two full orbits thus connected, they finally fired an explosive squib to jettison the tether at 7:37 pm on 13 November.

Aldrin’s record-breaking five and a half hours of cumulative extravehicular experience concluded the following day, the 14th, when he ventured outside at 9:52 am for a second stand-up period, lasting 55 minutes. He dumped unneeded equipment overboard, together with a sack containing his umbilical tether and two rubbish bags – hurled in lazy arcs over his shoulder – and took one last lingering

Aldrin during one of his three periods of EVA.

look at Earth below him: the vast land mass of Indochina… and thought of his friend, Sam Johnson, with whom he had undergone flight training, and who was at that very moment a prisoner of war somewhere in North Vietnam.

Lovell and Aldrin’s four-day mission had brought Project Gemini to a spectacular conclusion and had satisfactorily demonstrated rendezvous, docking, gravity gradient tethered operations and the ability of skilled human pilots to calculate a rendezvous with sextants and charts and a slide rule and pencil. Such human skills, using, in Aldrin’s own words, the Mark One Cranium Computer, had relaxed managers’ concerns about the viability of astronauts being able to perform a manual rendezvous, if necessary, in orbit around the Moon.

Gemini XII’s problems were comparatively minor. Four of its 16 thrusters failed during the course of the mission and two its six fuel cells went dead, obliging flight controllers to instruct Lovell and Aldrin to drink more than their planned rations of water. This would make room for the excess fuel-cell water, which otherwise threatened to flood the spacecraft’s power system. Whenever they drank water or used it to prepare their food, the red warning light blinked off, and in this way they nursed the fuel cell through 80 hours of flight.

A re-entry controlled completely by the computers brought Gemini XII into the Atlantic, barely 4.8 km from its target impact point, at 2:21 pm on 15 November. Within half an hour of splashdown, Lovell and Aldrin were safely aboard the aircraft carrier Wasp. The only unexpected event during re-entry had come at the onset of peak G loads, when a pouch containing books, filters and equipment broke free from the sidewall and landed on Lovell’s lap. By this time, both men had unstowed the D-rings for their ejection seats and Lovell fought the urge to catch the pouch, lest he accidentally grab and pull the ring. “I didn’t want to see myself punching out right at this high heating area,’’ he said later.

With the safe return of Lovell and Aldrin to Earth, many of the procedures needed to get to the Moon and back had been thoroughly tested. Extravehicular suits had been used for extended periods of time and five astronauts had completed useful tasks outside. Unlike Alexei Leonov’s swim in the void 20 months earlier, they had actually begun to demonstrate an astronaut’s ability to really work in space. It provided the closest analogue yet attained of what working on the lunar surface might be like. Rendezvous, despite its complexity, had been completed with seemingly effortless ease by six Gemini command pilots… and Lovell and Aldrin’s work had shown it could be done without the aid of radar.

The radiant Moon above Cape Kennedy in the early winter of 1966-67 seemed considerably brighter than normal, as an altogether different kind of space vehicle geared up for its first manned shakedown cruise. Sitting on Pad 34 was a far larger rocket – the Saturn 1B – topped with the Apollo 1 spacecraft. In February 1967, astronauts Gus Grissom, Ed White and Roger Chaffee would evaluate the machine that would carry Americans to the Moon. Forget 1970, said many within NASA; it was becoming increasingly likely that a lunar landing might be achieved two years ahead of schedule. For ten euphoric weeks from mid-November 1966, the Moon was within humanity’s grasp. Then, on the fateful Friday evening of 27 January 1967, all such dreams dissolved.

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