While NASA is still a couple of decades away from sending humans to Mars, it’s making critical progress with its Asteroid Redirect Mission (ARM), which will collect a boulder off a near-earth asteroid and bring it to lunar orbit in order to figure out how these gigantic space rocks can best serve deep space missions. Along the way, ARM will test out a whole bunch of new technologies in the process.

“This mission is very much how we can rebuild the building blocks to enable human exploration to Mars,” said NASA engineer Ben Cichy in a Facebook livestream on Wednesday about the ARM program from Goddard Space Flight Center in Greenbelt, Maryland.

Dark carbonated asteroids may hold up to 20 percent water, making them of use for both astronaut hydration and rocket fuel. But NASA will only be able to access those rocks with the successful deployment of newly designed robotics systems. The capture module for the mission will come equipped with 15-foot legs, two six-foot arms that function like human arms, and hands that allow for the precision gripping. Engineers at the Langley Space Center have invented gripping technology fitted with hundreds of little hooks to hold on to samples, with a drill component designed to anchor the boulder.

NASA has not announced a partner for the ARM’s actual shuttle design, but the live stream included a sneak peak of the master reference design. Critical to the mission’s ability to survive deep-space travel is the design’s “next generation of solar electric compulsion” panels. The panels, which are nearly the size of half a football field, will provide 250 kilowatts of power and eliminate the needs to carry lower-efficiency fuel, making more space for cargo and astronauts.

NASA is also looking to use ARM to learn how to deflect potentially dangerous asteroids. The capsule will be equipped with a gravity tractor that, in the course of 30 days, would presumably be able to deflect an asteroid enough to change its trajectory on a path that’s a safe distance away from the planet.

The ARM mission isn’t scheduled to launch until the end of December 2021. Researchers are holding off on choosing an asteroid to target in order to “see what other discoveries come out between now and 2021,” said Cichy.