Testing Rocks on Earth to Help NASA’s Perseverance Work on Mars NASA’s Mars Exploration Program – NASA Mars Exploration

Using carefully selected terrestrial rocks, engineers try to figure out how to work with crumbly rocks like the one the rover encountered on its first sampling attempt.

Not long after, Perseverance successfully gathered a sample the size of a piece of chalk from a different rock. The team concluded that the first rock they had chosen was so crumbly that the rovers percussive drill likely pulverized it.

But engineers at NASAs Jet Propulsion Laboratory in Southern California, which manages the mission, want to understand why that first sample, nicknamed Roubion, turned to dust. The missions scientists and engineers had run extensive test campaigns on dozens of rock types prior to launch, but they hadnt seen any react exactly like Roubion. So a new test campaign was started one that would include a field trip, a duplicate of Perseverances drill, and JPLs unique Extraterrestrial Materials Simulation Lab. Answers remain elusive, but heres a closer look at the process.

How Do Spacecraft Deal with Dust Storms on Mars? Get the latest on the rest of NASAs Mars fleet with the Mars Report. The new installment focuses on the Red Planets recent dust storm. Watch how the agencys orbiters supported the InSight lander as its power plunged during the January event. Credits: NASA/JPL-Caltech/ASU/MSSS. Download video Remembering Roubion

Re-creating the unique physical properties of Roubion would be key to the test campaign.

Of the rocks weve seen, Roubion had the most evidence of interaction with water, said Ken Farley of Caltech, Perseverances project scientist. Thats why it fell apart.

Rocks altered by water can be more susceptible to falling apart; theyre also highly valuable to Perseverances scientists. Water is one of the keys to life at least on Earth which is why Perseverance is exploring Jezero Crater. Billions of years ago, Jezero contained a river-fed lake, making it an ideal spot to look for signs of ancient microscopic life now. Perseverance is collecting samples that future missions could bring back to Earth to be studied in labs with powerful equipment too large to be sent to Mars.

Field Trip

It was very physical work, said JPLs Louise Jandura, chief engineer for sampling and caching, who has been leading the test campaign. We were chipping away with rock hammers and crowbars. A couple rocks were big enough that it took all five of us holding on to a stretched-out canvas to get it into the bed of our truck.

Next step: testing at JPL. One of the places where that happens is the Extraterrestrial Materials Simulation Lab, a kind of service center that prepares materials for testing elsewhere at JPL.

A Rock Superstore

The low-slung building sits on a hillside above the Mars Yard. Barrels out front contain reddish dust called Mojave Mars Simulant, a special recipe for re-creating the messy conditions rovers travel in. Piles of rocks some peppered with drill holes are strewn about a forbidding industrial saw near the entrance. In back stands a concrete bunker with rock bins labeled with names that sound like Mad Libs for geologists: Old Dutch Pumice, China Ranch Gypsum, Bishop Tuff.

I like to say we do artisanal selection and preparation of materials, said Sarah Yearicks, a mechanical engineer who leads the lab. Testing them is part manufacturing and part mad science.

Yearicks is one of the people who picked out the rocks at the Santa Margarita Ecological Reserve excursion. For the testing on Roubion-like rocks, Yearicks team worked with a construction-grade drill not a coring drill along with other tools, while Janduras team used a flight-like duplicate of Perseverances drill.The teams passed the rock samples back and forth, testing them in different ways.

Put to the Test

Janduras team ran their flight-like drill a few millimeters at a time, stopping to check that a core was still forming; if it had crumbled, theyd look at variables that might be the cause. For instance, the engineers tweaked the drills rate of percussion and the weight placed on its bit. They also tried drilling into the rock horizontally instead of vertically, in case the build-up of debris was a factor.

For every adjustment they made, it seemed, a new wrinkle would emerge. One was that fragile samples can still resist the percussive drill. When Janduras team reduced the force of percussion to avoid powderizing the sample, the drill bit couldnt penetrate the surface. But choosing a spot that holds up to stronger percussion means choosing one that likely interacted less with water.

Perseverance has so far captured six samples from highly weathered, water-altered rocks, and the team knows its capable of many more. But their experience with Roubion has prepared them for some of the extremes Mars will throw at Perseverance in the future. If they find more rocks like Roubion, the Extraterrestrial Materials Simulation Lab will be ready with its menagerie of Mars-worthy materials.

More About the Mission

A key objective for Perseverances mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planets geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASAs Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

and

nasa.gov/perseverance

News Media Contacts

Andrew GoodJet Propulsion Laboratory, Pasadena, Calif.818-393-2433andrew.c.good@jpl.nasa.gov

Karen Fox / Alana JohnsonNASA Headquarters, Washington301-286-6284 / 202-358-1501karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov

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Testing Rocks on Earth to Help NASA's Perseverance Work on Mars NASA's Mars Exploration Program - NASA Mars Exploration