The Apollo astronauts might have been in peak physical condition, but that doesn’t mean they didn’t suffer all sorts of health complaints. In space, no-one can hear your sneeze.

24: Number of decongestant tablets taken by the Apollo 7 crew

Launched on 11 October 1968, Apollo 7 was the first manned test of the Apollo spacecraft in Earth orbit. After the deaths of the Apollo 1 crew in a fire, the command module had been completely redesigned.

There was a lot resting on this mission. If Apollo 7 failed, it’s likely that Neil Armstrong would never have made his small step. At least, not by the end of the decade – the target set by President John F Kennedy in 1961.

Apollo 7 was commanded by one of Nasa’s most experienced astronauts, Wally Schirra - a veteran of both Mercury and Gemini missions. Alongside him in the capsule, rookie astronauts Don Eisele and Walt Cunningham. Commentators predicted this would be the crew to make the first attempt to land on the Moon.

Within hours of launch, however, Schirra came down with a cold.

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“The impact of Wally’s cold was tremendous,” says Cunningham. “Wally had to blow his nose pretty regularly and he would blow his nose once and fold the Kleenex away – after a couple of times, Don and I said, ‘No, no, you’re going to have to use those Kleenex more than that.’”

But, with used tissues stuffed in every corner of the capsule, the cold wasn’t just unpleasant for the crew. Schirra’s illness made him tired and irritable, and this was reflected in his communications with the ground.

“It was a very interesting relationship between those of us in mission control and the crew,” says Gerry Griffin, a flight director in mission control.

In a series of tetchy exchanges, Schirra refused instructions, argued with procedures and even told his boss – fellow Mercury 7 astronaut Deke Slayton – to go to hell.

“To this day, to a certain degree, it’s baffling to me,” says Griffin. “I was shocked, I really was.”

After 11 days in orbit, the crew returned to Earth. The mission was a technical triumph, proving the capabilities of the Apollo spacecraft.

Over the course of the mission, Schirra exhausted the supply of tissues and all 24 of the decongestant tablets carried in the spacecraft medical kit. Unfortunately, his behaviour was seen as a reflection of the whole crew. None of them would ever fly in space again.

(You can hear more about the missions leading up to the Moon landing)

3: Cases of flatulence

Flight surgeons collected extensive data on Apollo crews, before, during and after their missions. Medical issues reported during flight included a rash caused by wearing a urine collection device too long, eye irritation and – most seriously during Apollo 15 – irregular heart rhythms. One astronaut pulled his shoulder taking a lunar core sample and, because they had to ration their water, the crew of Apollo 13 suffered dehydration.

I have the farts, again – John Young

Three astronauts reported instances of excessive wind – most likely caused by their diets. Doctors believed the heart scare during Apollo 15 was due to a lack of potassium. So, for Apollo 16, doctors increased the amount of citrus fruit in the astronauts’ meals.

When Apollo 16 commander John Young walked on the Moon, he shared his feelings on the new diet with his companion Charlie Duke. The comments were inadvertently relayed to mission control… and the wider world.

“I have the farts, again,” he tells Duke. “I don’t know what the hell gives them to me… I think it’s acid stomach, I really do.”

“I haven’t eaten this much citrus fruit in 20 years!” he adds. “And I’ll tell you one thing, in another 12 f****** days, I ain’t never eating any more.”

Flatulence in a confined spacecraft is bad enough but during the Apollo 10 mission, one of the astronauts failed to properly seal a faecal waste bag after going to the toilet. The resulting conversation concerns whose turd is floating around with them in the capsule.

150: Neil Armstrong’s heart rate as he descended towards the lunar surface

The commander of Apollo 11 was notoriously cool and collected under pressure. It’s what made him such an outstanding test pilot. During the mission, from launch to splashdown, Neil Armstrong’s average heart rate was 71 beats per minute.

At 1,000ft (300m), with fuel running low, it raced at 150 beats per minute and remained that way during landing

On 20 July 1969, separating from the command module, Armstrong and Aldrin fired the lunar lander’s descent engine to slow them down and drop them out of lunar orbit. As they descended towards the Moon’s surface, and with all systems nominal, Armstrong’s heart rate was still a relatively cool 110 beats per minute.

But when computer warning alarms sounded, Armstrong’s heart rate began to climb. It dipped again once Houston give the crew a ‘go’ to proceed but, as they neared the ground and their planned landing area turned out to be strewn with boulders, it rose again. At 2,000ft (600m) Armstrong’s heart was 120 beats per minute. At 1,000ft (300m), with fuel running low, it raced at 150 beats per minute and remained that way during landing.

Two minutes later, when mission control gave the approval to ‘stay’ and tensions eased, the commander’s heart rate dropped back to normal.

Apart from the scare during Apollo 15, one of the highest heart rates ever recorded in space was during Gemini 9. On the final day of the mission, astronaut Gene Cernan had to spacewalk to put on a rocket-powered backpack stowed at the rear of the spacecraft. As he tried to manoeuvre and activate the device without handholds or tethers, he quickly became exhausted. 

“It was a terrible plan,” Cernan told me in an interview a few months before he died. “Every time I turned a valve, it turned me.”

“My heart rate was going 170 beats per minute, the doctors were going bonkers – they didn’t know what to do, they knew I was in trouble.”

Dangerously overheating and with his visor fogged up with perspiration, he managed to squeeze back into the spacecraft and close the hatch.

“Tom [Stafford] finally pressurised the spacecraft and I could take a breath,” Cernan recalled. “When I got my helmet off, he said I looked like a turnip… and he took the watergun and just squirted me with it.”

0.2: Total radiation exposure of the Apollo 11 crew in rads

The first US satellite, Explorer 1, discovered belts of intense radiation – termed the Van Allen belts – encircling the Earth. Even by racing through them and skirting the most intense areas, there was real concern that astronauts might not survive the journey to the Moon and back.

In 1966, the Soviet Union flew two space dogs through the belts without them seeming to come to any harm. But Nasa doctors were still worried about the effects on humans. So when the commander of Apollo 8 – the first mission to leave Earth orbit – became sick, the first thought was that he had radiation sickness.

Frank Borman hadn’t had any medical problems on his previous 14-day Gemini 7 flight. Nor had the crew of Apollo 7, orbiting the Earth, experienced any nausea. But as the Apollo 8 spacecraft left Earth orbit, Borman was vomiting.

We know now that Borman was experiencing the common symptoms of space sickness – caused by weightlessness – and, within hours, he had recovered. His Apollo 8 mission became one of the most daring and successful missions in space history.

According to the official Apollo 11 flight report, the 0.2 rads (0.002 grays in today’s standard international units) experienced by the crew “fell below the medically significant level”.

21: Days in quarantine after returning from the Moon

When the crew of Apollo 11 splashed down in the Pacific Ocean, they weren’t greeted with hugs and handshakes. Instead, as the recovery team came alongside in a boat, they opened the hatch, threw three biological protection suits inside and sealed the hatch again.

When the crew finally emerged, they were encased in these suits – their faces hidden behind respirators. Only once they had been helicoptered to an aircraft carrier – USS Hornet – and entered a specially adapted Airstream caravan, could they take the suits off and breathe normally.

The sleek, silver Airstream was known as the Mobile Quarantine Facility (MQF) and was designed to protect the Earth from any potential Moon bugs – infections from pathogens in space. Inside, the crew could relax and be monitored for any ill effects of their voyage to the Moon. Similarly, anyone handling the samples of Moon rocks the astronauts brought back were also kept in quarantine and under observation.

“It’s a standard Airstream trailer built on an Air Force cargo pallet so they could be loaded on a cargo plane,” says Bob Fish, trustee of USS Hornet, now preserved as a museum in Oakland, California. The MQF from Apollo 14 is on display in the ship’s hangar deck. Fitted with an air-filtration system, kitchen, living and sleeping areas, Fish says it was relatively luxurious.

“Three guys were in that tiny little space capsule for seven to eight days crawling all over each other, with no privacy, no sleep,” he says. “So this actually looked like the Taj Mahal to them – they had their own bunks, they had a toilet, they had a shower facility, they had a nice place to eat real food.”

The quarantine period – in the trailer and later in facilities at Houston – also gave the Apollo 11 crew a chance to gather their thoughts and write their mission reports, before they set off on a world tour as the most famous people on the planet.

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