The surface of the Moon is a harsh environment with no air, low gravity, dust, and micrometeorites—tiny rocks or metal particles—flying faster than 22,000 mph. These conditions can pose a hazard to astronauts, their dwellings, and spacecraft.
Engineers at NASA Glenn Research Center’s Ballistic Impact Lab are working to help the agency select materials for future Artemis missions and predict how they will perform while on the lunar surface.
The innovative lab, which features a 40-foot-long air gun capable of firing at velocities of 3,000 feet per second, has become a go-to destination for NASA as it examines situations ranging from the effects of bird collisions with aircraft to ballistic impacts on spacecraft.
Now, the team has been called to test several different textiles that will protect humans during Artemis missions to the Moon and beyond.
“If the object is pressurized, a leak can be catastrophic depending on how big and fast the leak is,” said Mike Pereira, the Ballistic Impact Lab’s technical lead. “Running this type of ballistic impact test is essential to a variety of NASA aeronautics and space exploration missions to ensure equipment and materials reliability.”
In the first series of tests, the team evaluated materials NASA is considering for habitats, which are designed to be relatively soft and flexible, but very stiff if struck.
To assess the potential fabrics and gauge how many layers would be needed to stop micrometeorite penetration, engineers used the facility’s air gun to fire steel ball bearings at various fabrics. The team connected the air gun to a vacuum chamber to remove air resistance, allowing it to shoot faster, while a suite of sensors and high-speed cameras measured how each material absorbed or deflected energy.
The resulting impacts take each fabric to the brink of failure to better understand the upper limits of durability and to ensure each can handle the harsh, punishing environment of space exploration.
Other materials tested included spacesuits that could be used for extravehicular activities on the lunar surface and in orbit. Understanding how materials respond to impacts is important for astronaut safety, according to Pereira.
The composite materials were a combination of substances that include fibers for strength and bonding resins to allow transfer of stress and energy. To evaluate these potential materials, engineers used the lab’s vertical-impact-drop tester to hurl mock simulated Moon rocks made of basalt onto potential spacesuit materials.
Engineers at NASA’s Johnson Space Center are analyzing the ballistics testing data to determine which materials will be best for a variety of lunar exploration items.
The next challenge for the Glenn team is testing materials that could capture space debris. New types of aerogels that are lighter and stronger might be the key to developing and deploying in-space devices given ease of use and reduced mass for launch.