On the launchpad and ready to go, NASA’s Perseverance rover is just hours away from beginning its challenging seven-month journey to Mars.
Besides looking for evidence of ancient life on the red planet and gathering samples of rock and soil for later return to Earth, the rover will also conduct research for those tasked with planning NASA’s first crewed mission to Mars, which could take place in the 2030s.
The research will involve testing various spacesuit materials to see how they stand up to the harsh Martian environment, which has a thin atmosphere and allows more radiation from the sun and cosmic rays to reach the ground.
The materials
NASA’s Amy Ross, who must be the envy of many with her “spacesuit designer” title, said in a recent piece on NASA’s website that Perseverance will be taking with it five materials designed for the outside of a spacesuit.
One of them, ortho-fabric, is already used on current spacesuits. It actually consists of three materials: Nomex, a flame-resistant material found in firefighter outfits; Gore-Tex, which is waterproof but breathable; and Kevlar, a strong synthetic fiber that’s been used in bulletproof vests.
Another of the material samples heading to Mars is Vectran, a cut-resistant material that’s currently used on the palms of spacesuit gloves. Ross said that its toughness makes it useful for astronauts conducting spacewalks on the International Space Station (ISS), where micrometeoroids sometimes strike handrails outside the orbiting outpost, creating pits with sharp edges that would damage less robust gloves.
Perseverance is also taking with it a sample of Teflon, a material long used on astronauts’ glove gauntlets and also the backs of the gloves.
“Just like a nonstick pan, it’s slippery, and it’s harder to catch and tear a fabric if it’s slick,” Ross said, adding that NASA is also sending a sample of Teflon that has a dust-resistant coating.
A piece of polycarbonate is also heading to Mars. Used for helmet bubbles and visors, the material helps reduce an astronaut’s exposure to ultraviolet light. “A nice thing about it is it doesn’t shatter,” Ross explained. “If impacted, it bends rather than breaks and still has good optical properties.”
Can they handle Mars?
The materials will be analyzed by one of Perseverance’s scientific instruments — called SHERLOC — that will also be searching for signs of ancient life. SHERLOC will be able to assess the condition of the spacesuit materials to see to what extent the radiation breaks down their chemical composition. If they stay strong, NASA can use them for crewed missions to Mars. If not, it’ll have to start work on creating more durable materials.
Martian dust
Martian dust also presents a challenge for crewed missions to the faraway planet, though Ross said her team is already developing things like seals that can keep dust out of the spacesuit bearings at the shoulders, wrists, hip, upper thighs, and ankles that give an astronaut mobility for walking, kneeling, and other movements. “We are looking for other ways to protect the suit from Martian dust over a long-duration mission,” Ross said. “We know that a coated or film material will be better than a woven material that has space between the woven yarns.”
Mars and the moon
Comparing the environment of Mars with that of the moon, Ross said that while the conditions differ, “the durability challenges — materials exposed over long periods of time at low pressures in a dusty environment — are similar.”
She continued: “Mars spacesuits will be more like ones we use for the moon and less like those for the ISS. I’m trying to make the moon suit as much like the Mars suit as possible.”