Why did American astronauts have to be quarantined when returning to Earth?

Returning to Earth in July 1969, astronaut Neil Armstrong had to celebrate his 39th birthday in quarantine. This was to prevent the risk of him being infected with a strange virus on the Moon.

During the Covid-19 pandemic, quarantine has become an effective measure to concentrate people at risk of infection, helping to limit the spread of the virus to the community. More than 50 years ago, the US government applied this measure to three NASA heroes - Neil Armstrong, Michael Collins and Edwin Aldrin - after they returned to Earth on July 24, 1969.

Notably, Mr. Armstrong celebrated his 39th birthday during the 21-day mandatory quarantine. Although he did not have many relatives around, his birthday in the quarantine area was still filled with joy, according to CNN.

The party included a cake and candlelight dinner. The cake was made by workers at the Lunar Receiving Laboratory at the Johnson Space Center in Houston, Texas, where the astronauts are quarantined.

After blowing out the candles, Armstrong passed out the cake to the quarantine staff and crew. Across the room, through a glass partition, the astronauts' wives were celebrating Armstrong's birthday. He pretended to pass them the cake, too.

Neil Armstrong's birthday was celebrated in quarantine. (Photo: CNN).

Journey after return

At that time, many science fiction movies conveyed the fear of contracting diseases from space, so the quarantine was to ensure everyone's safety, because the astronauts could have been exposed to harmful bacteria from the Moon.

The Apollo 11 mission was the first time humans had interacted with the surface of another celestial body. Doctors closely monitored the three astronauts. Another team examined and studied the moon rocks and dust that Armstrong and his crew brought back.

Scientists want to protect any organisms from the Moon that might survive Earth conditions. The samples are stored in a vacuum to avoid being affected by Earth's environment.

Upon landing in the Pacific, Armstrong's team was picked up by helicopter and taken to the USS Hornet aircraft carrier. They were then suitably protected and isolated in silver vehicles. All of the ship's equipment was also thoroughly disinfected.

President Richard Nixon welcomes the astronauts back. (Photo: CNN).

Moon Rock Research

Forty-eight hours after the spacecraft returned to Earth, samples and films taken on the Moon were processed and examined. Armstrong's team collected more than 22 kilograms of objects. The lab will test them for gamma radiation or microorganisms.

NASA said the space where the specimens were studied was even cleaner than a sterilized operating room.

Scientists do not believe life exists on the Moon, but they are not completely ruling out the possibility until they complete their study of the samples.

Additionally, scientists have discovered intriguing properties in lunar dust and rocks, such as their high titanium content.

A scientist studies a sample brought back from the Moon. (Photo: CNN).

The results of the study of the specimens showed no evidence of life or any toxic substances in the specimens. Living organisms, such as cockroaches, were also exposed to the specimens. They did not experience any adverse or unusual effects.

Later, the crews of Apollo 12 and 14 followed a similar quarantine procedure.

However, by the time Apollo 15, 16, and 17 began, NASA believed that quarantine was no longer necessary. After an initial medical check-up, the astronauts would be free to return to their normal lives.

When humans return to the Moon in 2024, quarantine after returning to Earth will also not be necessary, said Nilufar Ramji, a communications specialist at NASA's Johnson Space Center.

Astronaut's quarantine life

During the quarantine period, medical staff will check regularly to ensure the astronauts are not adversely affected by the spacecraft or any potential pathogens.

Lab workers are regularly monitored for their health. Even their waste is tested. This is to ensure that if someone is infected with the virus, the pathogen does not escape their body and spread outside.

The entire quarantine process was monitored from the outside by two doctors. Representatives from the World Health Organization (WHO) also inspected the laboratory.

Astronauts live in a mobile quarantine chamber provided by Airstream. (Photo: CNN).

As for the astronauts, they played cards, read magazines, and listened to news about the mission. They also tried to respect each other's privacy as much as possible. For example, when Aldrin talked on the phone with his wife, Collins wore headphones, and Armstrong played the ukulele.

Much of the astronauts' time in quarantine was spent reflecting on and learning from the trip. Each man went into a glass-enclosed room and discussed various aspects of the trip with NASA staff.

The final quarantine gate opened on August 10, 1969. The astronauts were able to walk around Texas at night, their first time outside and interacting with the outside world, after a long period of isolation during and after the mission.