Posted
Early on the morning of December 21 half a century
ago, the US space program tossed a coin when it launched the first
manned mission to the Moon.
Key points:
- NASA estimated the Apollo 8 astronauts only had a 50-50 chance of survival
- Apollo 8 was the first Saturn V rocket launch and the first time people left Earth's gravity
- Flying without a lunar module, the crew had no back-up plan in case of failure
NASA insiders have admitted the risks they took to get Apollo 8 into lunar orbit for Christmas in 1968 would make the following year's Moon landing seem easy by comparison.
As Apollo 8 vanished behind the Moon on Christmas Eve, billions of people back on Earth held their breath — not knowing whether astronauts Frank Borman, Jim Lovell and Bill Anders would ever be heard from again.
They were flying backwards, in readiness for the four-minute service propulsion system (SPS) engine burn that would slow them down to a stable orbital speed.
Halfway through that burn and feeling the tension, Lovell told his crewmates it felt like the longest four minutes of his life.
They were about to become the first people alive to gaze upon the lunar far side, the hemisphere of the Moon permanently facing away from Earth.
But at that moment there was no time to look out the window — if they couldn't shut the SPS down again it would slow them down so much they would crash into the lunar surface.
The SPS had never before been pushed to this extent, and there was no back-up plan if it failed, so NASA bosses had privately estimated the Apollo 8 crew only had a 50-50 chance of making it home alive.
Anders later admitted he thought their chance of survival was more like one in three, while Susan Borman was utterly convinced she was sending her husband to his death.
But the SPS shut down on schedule, finally allowing them to take a look at where they were.
The lunar surface felt almost close enough to touch.
A rapid of change of plan
Early in 1968, the plan for Apollo 8 was a relatively straightforward Earth orbit, a chance to test the functioning of the lunar module (LM) for later Moon missions.But by mid-year, Grumman Aircraft was behind schedule in constructing the LM and NASA realised it would not be ready in time for the Apollo 8 launch.
NASA senior managers had also been handed a top secret US intelligence memo warning the Russians could be ready to send a manned mission to the Moon before the end of the year.
The USSR had already claimed so many firsts in space. For NASA, it was simply not an option to be beaten to the Moon.
The Apollo program was dedicated to honouring president John F Kennedy's 1961 promise to land men on the Moon before the end of the decade.
Sending a manned mission into lunar orbit was a critical first step, so with time certainly not on their side, NASA cobbled together a new mission plan for Apollo 8.
Borman, now 90 years old and still going strong, said earlier this year he still remembered that moment vividly.
Speaking in April at the launch of Rocket Men — the latest book about this pivotal moment in US space history — Borman said NASA normally spent six months developing a mission plan, but Apollo 8 was nutted out in a single afternoon.
They would have no LM (meaning no back-up vehicle), but they could still beat the Russians to the Moon.
Rocket Men author Robert Kurson said one of the men responsible for the flight summed up the move:
"For NASA's legendary flight director Chris Kraft it was simple — 'it took more courage to make the decision to do Apollo 8', he said, 'than anything we ever did in the space program'."
Borman knew the risks they were being asked to take, but he was never going to turn down a flight to the Moon.
"I looked around the room at that meeting and there were people who knew what they were doing — fortunately there wasn't anybody there from Washington," Borman said.
"They all, from Jim Webb the administrator down to the lowest employee at NASA, wanted to win, wanted to beat the Russians to the Moon."
First people to leave Earth's gravity
The Apollo 8 crew were the first people to ride one of the massive Saturn V rockets into space. Up to this point, the Saturn V had only launched unmanned missions.
Landing on the Moon meant sending not one but two spacecraft into orbit — the command/service module and the LM.
The Saturn V was the behemoth designed to get that heavier payload into space.
From the top of the launch tower, Lovell remembered looking down at the ground moments before he was strapped inside their capsule.
"I could see the lights of the press corps coming into their spots about that time and I thought to myself, 'They're gonna send us to the Moon!'"
Anders said the Saturn V rocket engines burnt 15 tonnes of fuel per second.
"When the rocket lit off, it was so noisy," he recalled.
"It was so noisy that had I noticed anything wrong on the instrument power, which was vibrating like mad and I couldn't see it anyway, I couldn't have communicated to them [NASA ground control].
"As we lifted slowly the huge engines were gimbaling down at the bottom — we were like a ladybug on the end of an old-fashioned antenna on your car, it was violent.
"Frank was smart enough to take his hand off the abort handle for fear. Like any other fighter pilot, he'd rather be dead than screw up."
Australia's critical role in the mission
It took them almost three days to reach the Moon. As they gradually escaped Earth's gravitational influence, the planet got smaller and smaller through the window.Then came the loneliest moment of all, when they had to disappear behind the Moon, cutting all communication with Earth.
In Australia, NASA's Honeysuckle Creek signal relay station, south of Canberra, played a critical role in linking Apollo 8 with mission control in Houston.
Honeysuckle's operations supervisor at the time, John Saxon, told the ABC he remembered Apollo 8 clearly.
"We had the lion's share of that mission," he said.
"The Moon was very much in the southern hemisphere so we had the majority of the view of the Moon and I do believe we were the only site in view.
"We were the only lunar distance station in the southern hemisphere. We did all the data processing and the television processing and all the rest of it.
"There was very little remote control or automation in those days, just about everything was operated by technicians and people at the equipment."
Honeysuckle Creek was purpose-built for lunar missions.
"So when we got to Apollo 8 it was what we were designed for and what we had trained for, it was a magic mission," Mr Saxon said.
"It was the first time that man had gone more than, I think 850 kilometres away from the surface of the Earth and here they were out at the Moon's distance which was some 360,000 kilometres."
He said he distinctly remembered the moment Apollo 8 vanished behind the Moon, because Honeysuckle Creek would be first to know when the spacecraft reappeared.
"When they came out from behind the Moon, they were spot on time," he said.
"There was only one problem — we had configured all these back-up modes of operation, that they might have possibly come out from behind the Moon onto the lunar module voice bus in the station.
"So we had two sources of modulation from the spacecraft and two places it might have gone and the guy at the front who was sorting out where the signals were coming from … he was frantically trying to find and I was frantically trying to remote the correct source of information to Houston.
"I remember him saying, 'We've got data, but no voice'.
"The whole thing was a bit of a mess. My fingers were poised, I could have so easily become the first man to talk to anybody in lunar orbit by pressing the button and talking directly to them rather than going through the switching circuitry here on site.
"But we persevered and eventually we got it sorted out, so I missed my big opportunity."
The most famous photo of all time?
Apollo 8 is best remembered for an unexpected photograph captured by Anders in lunar orbit.Dubbed 'Earthrise', it showed a small blue-green planet rising from behind the pock-marked lunar surface just 60 nautical miles below them and set against the vastness of space.
Anders famously said: "We came all this way to explore the Moon, and the most important thing is that we discovered the Earth."
That year had been a terrible one for America. There had been riots in April after the fatal shooting of Martin Luther King Jr. Two months later, Bobby Kennedy was killed. In August, Chicago police and the national guard violently cracked down on anti-Vietnam protesters outside the Democratic National Convention, as the war itself went from bad to worse after the bloody Tet offensive in January.
After transcending that year of horror with their brave triumph, the crew of Apollo 8 were honoured as Time magazine's men of the year.
Plucked from among thousands of telegrams of congratulation, NASA relayed one notable message to the astronauts as they returned to Earth. A woman named Valerie Pringle wrote: "You saved 1968."
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