NASA's Perseverance rover isn't just searching for signs of ancient life on Mars, it's also testing spacesuit materials on the Red Planet. Scientists are studying the effects of radiation, extreme cold and corrosive dust on the samples after four years of harsh conditions. What they learn will help design better spacesuits for future astronauts, ensuring they can safely explore Mars in harsh conditions such as intense ultraviolet light and toxic salts.

NASA's Perseverance rover will land on Mars in 2021 with a mission to search for signs of ancient microbial life and study Mars' climate and geology. But one of its lesser-known goals is to support future human exploration. As part of this effort, Perseverance is carrying five small samples of spacesuit materials designed to test their ability to withstand the Martian surface.

The materials were exposed for four years to the extreme Martian environment - intense radiation, fine dust and temperature fluctuations - and are now being analyzed to understand how they changed. The goal is to better understand how long a spacesuit will remain functional on Mars.

Perseverance is helping scientists design future Mars space suits by testing material samples under real Martian conditions. After four years of intense radiation and dust, early signs suggest the material degrades rapidly, providing key insights into safer exploration gear. Image source: NASA/JPL-Caltech

“This is one of the forward-looking aspects of the Mars Rover mission—not just thinking about current science, but also what’s next,” said Marc Fries, a planetary scientist at NASA’s Johnson Space Center in Houston, who helped provide the suit materials. "We are preparing for eventual human exploration of Mars."

Each color plate measures three-quarters of an inch square (20 mm square) and is part of a calibration target used to test the SHERLOC (Scanning Habitable Environments Using Raman and Luminescence to Detect Organics and Chemicals) setup. SHERLOC is an instrument at the end of Perseverance's robotic arm.

Samples include a piece of polycarbonate helmet visor; Vectran, a cut-resistant material used on the palms of astronaut gloves; two types of Teflon with dust-resistant and non-stick properties; and Ortho-Fabric, a common space suit material. This last fabric has multiple layers, including Nomex (a flame-retardant material used in firefighter clothing); Gore-Tex (waterproof but breathable); and Kevlar (a strong material used in bulletproof vests to make space suits more resistant to tears).

On the left is NASA's Perseverance Mars rover, and the circle indicates the location of the probe's SHERLOC instrument calibration target. On the right is a close-up of the calibration target. At the bottom are five samples of spacesuit material that scientists are studying to degrade. Image source: NASA/JPL-Caltech/MSSS

Mars is far from a habitable place. Mars is so cold that fine dust clings to solar panels and spacesuits (causing the suits to wear out), and the surface is filled with perchlorate, a corrosive salt that is toxic to humans.

Mars also has a lot of solar radiation. Unlike Earth, whose magnetic field deflects most solar radiation, Mars lost its magnetic field billions of years ago, and subsequently much of its atmosphere. The Martian surface has little protection against the sun's ultraviolet rays (which is why researchers have been studying how rock formations and caves could offer astronauts some protection).

This image shows a spacesuit prototype (left) and a spacesuit sample in a calibration target (lower right) belonging to the SHERLOC instrument on the Perseverance rover. Researchers will observe them to see how long they can survive the intense radiation on the Martian surface. Image source: NASA

"Mars is a really harsh and difficult place," said Joby Razzell Hollis, a member of the SHERLOC science team at the Natural History Museum in London. "Don't underestimate this - especially as the radiation is so severe."

Razzell Hollis served as a postdoctoral researcher at NASA's Jet Propulsion Laboratory in Southern California from 2018 to 2021, where he helped prepare SHERLOC for the Mars landing and participated in science operations after the rover landed. He has previously studied the chemical effects of sunlight on a new type of solar panel made of plastic, as well as the impact on plastic pollution floating in the Earth's oceans.

He compared the effects to white plastic lawn chairs that turn yellow and brittle after years in the sun. Much the same thing happens on Mars, but weathering may be faster because of the stronger ultraviolet radiation on Mars.

The key to developing safer spacesuit materials is understanding how quickly they wear out on the Martian surface. About 50 percent of the changes SHERLOC observed in the samples occurred during Perseverance's first 200 days on Mars, and Vectran appears to have changed first.

Another nuance is determining how much solar radiation different parts of the suit must withstand. For example, an astronaut's shoulders are more exposed than their palms and therefore may receive more radiation.

The SHERLOC team is writing a scientific paper detailing preliminary data on how the samples will perform on Mars. Meanwhile, scientists at NASA's Johnson Laboratory are eager to simulate the Martian weathering process in special chambers that simulate the carbon dioxide atmosphere, air pressure and ultraviolet light on the Martian surface. They can then compare the results produced when testing the materials on Earth to those seen in the SHERLOC data. For example, researchers can stretch materials until they break to check whether they become more brittle over time.

"Textile materials are designed to be both tough and flexible, so they protect astronauts but can bend freely," Freese said. "We wanted to know how much strength and flexibility fabrics lose over time. As fabrics weaken, they wear and tear, causing heat and air leaks from the suit."

NASA's Perseverance rover is a flagship mission to Mars, launching in 2020 as part of the agency's broader Mars exploration plans and its "Moon to Mars" strategy. Perseverance, built and operated by NASA's Jet Propulsion Laboratory in Pasadena, California, is exploring Jezero Crater, which is believed to have once contained a lake.

A major goal of the mission is astrobiology, specifically the search for signs of ancient microbial life. The rover is also studying Mars' geology and past climate to better understand its history and prepare for future human exploration.

Perseverance is the first mission to collect and store Martian rock and soil samples, which will be sealed in tubes for future return to Earth. The samples will be recovered through a planned Mars sample return campaign. This collaborative project between NASA and the European Space Agency (ESA) will allow scientists to study Martian materials in unprecedented detail from Earth.

Compiled from /ScitechDaily