Fifty-four years ago, NASA launched Apollo 11, the mission that would bring the first human beings to the surface of the moon.
But as scientists prepared, a new fear sprung up: what if the mission brought lunar microbes back to Earth, which could unleash a pandemic of unknown proportions?
Luckily, the moon didn't have any space diseases, mysterious lunar pathogens or any unknown biological material that astronauts could have taken back to Earth with them.
The key word here is "luckily," because a new analysis of NASA's quarantine protocols for Apollo 11 shows the mission's plan would not have been able to contain the dangerous lunar microorganisms that some scientists feared could break loose.
"Had Apollo 11 returned microorganisms from the moon, they would likely have escaped," Dagomar Degroot, an environmental historian at Georgetown University in Washington, D.C., wrote in a new paper .
The paper compiles the complicated, convoluted story of NASA and federal agencies trying to come up with a plan to avoid backward contamination of Earth from the moon, all while juggling political considerations and the risk to the human astronauts at the centre of the mission.
NASA officials knew there was a distant possibility that lunar microbes could pose a threat to the Earth if they existed 鈥� and according to Degroot's archival work, they knew that they couldn't stop them from escaping.
"As NASA prepared to land its astronauts on the moon, there was no way for scientists to know whether microbial life had evolved on or beneath the lunar surface," Degroot wrote. "If it had, federal officials privately agreed, the Apollo missions would release it into Earth's biosphere."
The story of NASA's 1969 plan to stop potential lunar microorganisms from contaminating the Earth is a strange tale of a high stakes risk-benefit calculation.
But while the quarantine plan of 1969 was plagued with problems, it does provide scientists with lessons to learn from should they discover actual microorganisms on distant planets, especially as NASA looks to conduct future missions to and into deep space.
MOON MICROBES?
Even in the 1960s, most scientists believed the moon to be biologically inert and that the existence of copious amounts of bacteria or lunar influenza floating around was unlikely 鈥� something we now know for a fact.
But at the time, scientists couldn't say the possibility of contamination was zero. Several experts suggested that there could be "transient lunar phenomena" or that life existed just beneath the surface of the moon. Planetary scientist Carl Sagan suggested that the moon could have microbial life if it is a reflection of what Earth looked like in the past.
Although Sagan hadn't yet achieved the fame he would go on to attain in the astronomy world, his warning was heard and repeated in congressional memos, Degroot wrote.
The distant possibility of unknown bacteria existing on the moon brought up a new fear for the experts planning the lunar missions: what if their history-making foray into space brought back something that could wipe out the human race?
NASA's focus in risk assessments, Degroot wrote, was on how to protect the astronauts and the lunar samples they would be taking home from danger, not necessarily on how to protect Earth from any pathogens the astronauts might carry home with them on their suits and equipment.
Meanwhile, federal regulators and scientists in other fields wanted to look at the risk level the missions posed to the U.S. itself and its population on the ground.
U.S. President John F. Kennedy had promised in 1962 to land a man on the moon before the end of the decade, and the U.S. was embroiled in a fierce space race with the Soviet Union. Any potential delays to the launch would have been a huge blow.
A plan needed to be made, both to soothe these fears and prepare for the worst.
The U.S. Congress authorized NASA to build a Lunar Receiving Laboratory (LRL) in Houston, where returning astronauts and their equipment would remain in quarantine to see if they posed any risks to people on Earth.
"Rough plans drafted by NASA officials imagined that, in the event of a dangerous breach of lunar organisms that threatened to spill beyond the LRL, guards would seal the facility at gunpoint," Degroot wrote. "If all else failed, the entire facility and everyone inside it would be buried under a mountain of dirt and concrete."
A LEAKY SHIP FROM THE START
The process of building and testing the LRL was a fraught one.
To start, it was built with the pyrogenic bacterium responsible for the bubonic plague in mind, Degroot wrote, a pathogen which lacked the bacterial spores that allow some bacteria to survive extreme conditions.
In early 1968, the chemist John Hodge suggested testing the facility with a different pathogen, one more suited to a hypothetical lunar environment.
He proposed Coxiella burnetii, which causes in humans. But the prospect terrified NASA.
"A test using C. burnetti would motivate a concerted effort to prepare the LRL for a lunar pathogen 鈥� but at the risk of sickening thousands of NASA employees on the eve of the first lunar landing," Degroot wrote.
The idea was scrapped. But with only a year left before launch, there was still no real plan for testing whether the LRL even worked as a quarantine facility, leaving engineers scrambling.
In October 1968, an exam turned up 82 problems with the LRL, including an issue with a supposedly airtight vacuum chamber called a "biocabinet," where you could place moon rocks and handle them with gloves.
"The gloves, however, cracked and leaked when exposed to the pressure difference in the biocabinets," Degroot wrote.
A later review in December found around 140 deficiencies. Further tests at the start of 1969 found that the autoclaves 鈥� essential steam sterilizers meant to kill bacteria on items placed inside 鈥� kept filling with water.
Degroot wrote that a 30-day test in March and April, which included mock lunar samples, had "alarming" results that showed the LRL was not as contained as previously thought and did not have the required contingencies.
There were issues beyond the LRL, such as the problem of how to contain potential pathogens as astronauts returned to Earth and splashed down in the Pacific Ocean.
Experts argued on whether or not the capsule should be ventilated as it touched down 鈥� which would lower the risk of astronauts overheating and getting carbon monoxide poisoning, but also greatly increase the odds of any pathogens from the moon being released into Earth's environment.
Despite all of this, the LRL was cleared and the launch went ahead with the shaky quarantine plan in place.
Mitigation efforts on the actual day included requiring Neil Armstrong and Buzz Aldrin 鈥� the two Apollo 11 astronauts who walked on the moon 鈥� to brush off as much moon dust from their spacesuits as possible and requiring the navy divers retrieving their space capsule to wear biological isolation garments, and bring extras for the astronauts.
Even once the launch was over, the quarantine period 鈥� astronauts had to spend three weeks in the LRL 鈥� was far from uneventful.
The film magazines used to take footage on the moon were meant to be quickly decontaminated at LRL, so that the public could see the footage as quickly as possible.
While attempting to clean the film, a technician found a note from Aldrin, which said he had dropped one of the magazines on the lunar surface. The magazine had moon dust on it, exposing the technician and four other workers. They later joined the astronauts in quarantine.
Obviously, no moon microbes took over the Earth as a result of the first moon landing. But this was because there were no moon microbes to do so, not because of any quarantine efforts from NASA, which Degroot described as too quickly set up to be effective.
"NASA managers feared that any delay would allow Soviet cosmonauts to reach the moon first," Degroot wrote. "Above all, it was this fear that encouraged the development of a flawed quarantine protocol that would have accelerated 鈥� rather than delayed 鈥� the release of lunar microorganisms on Earth."
LOOKING FORWARD TO MARS
It's no surprise to scientists today that the moon wasn't host to alien microorganisms.
But astronomers and astronauts have their eyes set on Mars next for samples and crewed missions.
Icy caps on the planet and evidence that there was once flowing water on the surface mean there could have been life on the planet in the past, making the chance of finding some sort of bacteria higher.
But instead of trying to solve the problem of back contamination on a tight deadline, NASA and other space agencies have already been working on the question of Mars contamination.
NASA's Office of Planetary Protection, which focuses on protecting both the Earth from space contamination and other planets and celestial bodies from terrestrial contamination, set for the construction of the sample tubes used by the ahead of its launch.
Perseverance is currently collecting samples on the surface of Mars, but the first samples aren't set to arrive back home to Earth until 2033 at the earliest.
NASA's plan is to have a launch to Mars in 2028 and take the sample tubes delivered by Perseverance. Once the samples are launched back into space, they won't head back to Earth right away.
First, the Capture, Containment, and Return System (CCRS), a specialized container attached to a spacecraft orbiting Mars, would handle the samples. would then study the samples on Earth.
NASA and the European Space Agency also announced a joint project in April to convene a to review the current plans for returning Mars samples.
The final report assessing the project's status, as well as its chances of success, is expected in late August.
