NASA begins testing robotics to bring back first samples from Mars – NASA’s Mars Exploration Program
Engineers are developing the essential hardware needed for a series of daring space missions to be carried out over the next decade.
Testing has already started on what would be the most sophisticated venture ever attempted on the Red Planet: bringing rock and sediment samples from Mars to Earth for further study.
The multi-mission Mars Sample Return campaign began when NASA’s Perseverance rover landed on Mars last February to collect samples of Martian rock looking for ancient microscopic life. Of the 43 Perseverance sample tubes, four were filled with rock cores and one with Martian atmosphere. Mars Sample Return seeks to bring selected tubes back to Earth, where generations of scientists can study them with powerful laboratory equipment far too large to be sent to Mars.
Introducing these samples to terrestrial laboratories would take a decade and would involve European partners and several NASA centers. ESA (the European Space Agency) is developing a rover for the effort, with engineers from NASA’s Glenn Research Center in Cleveland, Ohio, designing its wheels. The rover would transfer samples to a lander, under development at NASA’s Jet Propulsion Laboratory in Southern California, which would use a robotic arm (developed by ESA) to pack the samples into a small rocket, called the Mars Ascent Vehicle. , designed by NASA Marshall Space Flight Center in Huntsville, Alabama.
The rocket would be launched from the lander to deliver the sample capsule to an ESA spacecraft orbiting Mars. Inside the orbiter, the capsule would be readied for delivery to Earth by equipment that a team led by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is developing. This preparation would include sealing the sample capsule in a clean container to trap any Martian material inside, sterilizing the seal, and placing the sealed container in an Earth entry capsule prior to the return trip to Earth.
To develop the lander, as well as the system that would help launch the sample-laden rocket, engineers at NASA’s JPL draw on a long history of exploring Mars: JPL conducted nine successful landings on Mars. , including rovers and stationary landers. But the Sample Retrieval Lander would be the largest and heaviest such spacecraft to ever go to Mars, and the launch of the Mars Ascent vehicle from it would be the first rocket ever to be fired from another planet.
This is where the test comes in.
To transport and launch the Mars Ascent vehicle, the lander must be a sturdy platform, weighing approximately 5,291 pounds (2,400 kilograms) – almost twice as heavy as Perseverance, which was lowered to the Martian surface with cables. of a rocket-powered jet pack. The Sample Retriever Lander would not have a jet pack; its legs should absorb the impact of touchdown, relying on retro rockets to slow its descent, much like recent lander missions to Mars like InSight and Phoenix.
That’s why Pavlina Karafillis dropped a prototype lander – on several occasions – in a warehouse-like space at JPL. As a test engineer for the sample collection lander legs, she and her colleagues used high-speed cameras to watch this prototype’s legs slam onto a base. QR code-like markings on each of the prototype’s “feet” help cameras track movement of the legs. The team uses slow-motion video to continuously update their computer models, which helps them understand how energy would be dispersed throughout the lander.
“The last leg of the trip is really important,” said Karafillis. “There are all kinds of landing conditions you have to consider, like rocks, or very soft sand, or at an angle. That’s why we have to do all these tests.
Karafillis and his colleagues started with a prototype about a third the size of the actual spacecraft; a lighter prototype is one way to learn how the final design of the lander would move in the low gravity of Mars. Later in the program, they’ll also drop a full-scale lander.
But surviving the landing is only part of the challenge – safely launching the 2.8-meter-long double-decker rocket that will be on top of the lander bridge adds another level of difficulty. Mars’ gravity is one-third that of Earth, and the rocket’s weight, combined with its exhaust, could cause the lander to slide or tilt.
Engineers therefore devised a system to launch the rocket into the air just before it ignited. The whole process takes place with a snap of a finger, launching the rocket at a speed of 16 feet (5 meters) per second.
During testing, a cradle fitted with gasoline pistons launched an 881 pound (400 kilograms) dummy rocket 11 feet (3.3 meters) into the air; cables suspended from a 13-meter-high tower unloaded more than half the weight of the test article to simulate Martian gravity.
“It’s kind of like being on a really fast roller coaster when someone hits the breaks,” said Chris Chatellier, chief systems engineer at JPL. “There are a lot of security aspects to consider. The tests take place in a very controlled sequence of events with everyone outside the building. “
This system, known as the Vertical Ejection Controlled Tilt Release System (VECTOR), also adds a slight spin during launch, which raises the rocket upward and away from the Martian surface.
“Launching with VECTOR means the lander could be pointing the wrong way on a slope, and we could still achieve that,” Chatellier said.
Chatellier and his team performed 23 tests this year, changing the mass and center of gravity of the rocket along the way. They also added springs to the bottom of their undercarriage replacement, observing the “bounce” created by the launch system. Next year they will launch a heavier rocket even higher.
“We are on the right track,” Chatellier said. “Our analysis and our predicted models were very close to what we saw in the tests.”
Learn more about the sample return from Mars
NASA’s Mars Sample Return (MSR) will revolutionize our understanding of Mars by returning scientifically selected samples for study using the world’s most sophisticated instruments. The mission will fulfill a goal of exploring the solar system, a high priority since 1980 and the last two decadal planetary surveys from the National Academy of Sciences.
This strategic partnership of NASA and ESA (European Space Agency) will be the first mission to return samples from another planet, including the first launch and return from the surface of another planet. These samples collected by Perseverance during its exploration of an ancient river delta are considered the best opportunity to reveal the early evolution of Mars, including the potential for life.
More details on the sample return from Mars:
Jet Propulsion Laboratory, Pasadena, California
NASA Headquarters, Washington