This week, the National Aeronautics and Space Administration's (NASA) rover Perseverance, a part of the Mars 2020 mission, landed on Mars. While the world was abuzz with this incredible step for mankind, cleanroom technicians were also cheering loudly. Because there’s a tight link between cleanrooms and space as we take every precaution possible to keep space clean.
We talk a lot about cleanrooms being used in technology, pharmaceuticals, medical equipment manufacturing, and food production. But do you know why cleanrooms were originally developed? Some say the idea originated in hospitals during the 1800s, but today’s cleanroom technology was spurred by World War II’s weapon manufacturing and the following space race.
The now popular HEPA filter became available publicly in the 1950s and played a key role in helping to manufacture functioning spacecraft in the 1960s. Since then, the cleanroom has become a foundation of countless industries.
But space is where it all started. So why do cleanrooms and space go hand in hand?
Under the 1967 Outer Space Treaty, the United States is obligated to keep space as clean as possible. The purpose of this treaty is to prevent Earth’s contaminants from impacting celestial bodies while also protecting our environment from outside threats.
Basically, we want to keep Earth on Earth and space in space.
So how do we make this happen?
NASA has a Planetary Protection Office that creates standards to follow when constructing spacecraft to limit biological material from Earth being carried into space. According to NASA, “Flight hardware for the Mars 2020 Perseverance mission and the Ingenuity Mars Helicopter have been designed and built to meet NASA planetary protection requirements.”
The emphasis of this strategy is making sure that every piece of equipment going into space is biologically clean. When launched, the Perseverance rover, Ingenuity Mars Helicopter, cruise stage, aeroshell, and descent stage will have less than 500,000 bacterial spores on it. That sounds like a high number, but it wouldn’t even cover a camera lens on a cell phone. So it’s quite insignificant! On the equipment actually interacting with Mars’ atmosphere, there must be fewer than 300,000 spores. And Perseverance itself must have only 41,000 spores.
And they make this happen in cleanrooms.
Engineers used traditional positive pressure cleanrooms to build Perseverance and its necessary spacecraft. They followed stringent procedures to keep the air as clean as possible, while also instituting strict sanitizing measures. They used tried and true methods for eliminating biological contaminants, such as wiping equipment down with sterile wipes and alcohol wipes and heating appropriate parts to high temperatures.
They also implemented some new and exciting cleaning methods involving hydrogen peroxide vapor. The Mars 2020 spacecraft contained parts that could not be treated with other methods, so they used this vapor to remove contaminants.
So what did they pay the most attention to in assembling a clean rover? The pieces that would be used to pick up and store samples.
While the Planetary Protection is put into effect for every piece of equipment going to space, there were extra precautions taken with the Perseverance rover since it’s designed to collect samples.
These components were developed in an antiseptic room - basically a cleanroom’s cleanroom. And they followed protocols to keep the room cleaner than the tools used by surgeons.
These components were also stored in incredibly clean storage facilities and were only added to the rover shortly before launch to limit exposure. The door they are behind has extra barriers to prevent contamination and will only detach once the rover has landed.
When we’re studying extraterrestrial samples, we want to know for sure that what we’re seeing is from another planet or space. So cleanrooms are incredibly important for processing, studying, and storing these samples.
In 2018, scientists were given a scare when they realized one of their cleanrooms was contaminated with fungus. During a routine check at NASA’s Johnson Space Center (JSC) in Houston, Texas, they found between 4 and 28 viable cells in the Penicillium genus per sample area. They also found a heavy concentration in an air filter that hadn’t been opened for the past 40 years.
The room, at the time, was classified as an ISO class 6 cleanroom on the ISO scale of class 1 to class 9, with class being the cleanest. So it wasn’t incredibly surprising to find contaminants and particles in the room, but the shocking part was that 83% to 97% of the microbes were fungus. Since fungi can spread rapidly and contaminate samples easily, this was concerning. This specific cleanroom was being used to store and study samples such as the Apollo moon rocks.
It was a stark reminder to scientists that cleanrooms take effort to stay clean. And getting these samples is, of course, no easy feat. So when Perseverance returns its samples, scientists will take extra precautions to make sure that we know exactly what they are telling us about Mars - not Earth’s fungi.
To help in this effort, researchers also tracked any substances known to be on Perseverance before it was launched and that it might acquire during launch. So we can have the absolute clearest test results possible.
The drive for clear test results and keeping space clean has established a long history between cleanrooms and space. And the question exists: if we hadn’t had the furied space race in the 1960s, would we have cleanrooms as we know them today?
We might not. But the need for highly detailed and clean equipment that operates at a micro level and the obligation to keep Earth from impacting space’s cleanliness drove us to the technology we know and use today.
And in those cleanrooms, we have made thousands of incredible discoveries and advances in medicines, food production, technology, weaponry, and so much more.
All thanks to cleanrooms and space.
Want to know more about how we’re doing our part in keeping cleanrooms clean? Contact us today!