Perseverance Mars rover to begin caching samples
NASA’s Mars rover Perseverance is about to drop valuable cargo.
The car size Endurance Rover has collected samples of Martian rock, soil and air since landing in the red planet’s Jezero Crater in February 2021. This material will be returned to Earth by a joint NASA-ESA European Space Agency (ESA) campaign, if at all, as early as 2033 is on track.
The rover is nearing a major milestone in the sample return effort — the establishment of its first Mars sample repository, which is expected to begin in the next few days, NASA officials said in an update on Friday (December 16).
Related: 12 amazing photos from the Perseverance rover’s first year on Mars
Nicknamed the Three Forks, this depot in a flat patch of Jezero’s soil will consist of 10 sealed Titan Sample Tubes that Perseverance will drop over the course of approximately 30 days.
The samples destined for the repository “are an incredible quantity, representative of the area explored during the main mission,” said Meenakshi Wadhwa, principal investigator for the Mars Sample Return program at Arizona State University, in Friday’s update (opens in new tab).
“Not only do we have igneous and sedimentary rocks that show at least two and possibly four or even more different types of aqueous alteration, but also regolith, atmosphere and a witness tube,” she added. (Witness tubes are intended to help mission team members determine what materials, if any, in the collected samples could be contaminants from Earth.)
Billions of years ago, Jezero was home to a large lake and river delta, which is the main reason the crater was the target of the Perseverance mission. In addition to its work collecting samples, the rover is searching the rocks of Jezero for signs of life on ancient Mars.
To date, Perseverance has collected 18 samples (opens in new tab). On board, 15 tubes contain drilled cores from intriguing target rocks, two ports contain regolith (earth and gravel) and one is filled with Martian air. This “atmospheric sample” is the result of Perseverance’s first-ever sampling attempt, which failed due to the brittleness of the target rock.
The rover team collects two core samples from each target rock. Perseverance will keep one set on his body and drop the other set in caches like the one planned for Three Forks.
The baseline for returning Martian samples is for Perseverance to deliver its samples to a NASA lander with an onboard rocket, which will then place the material in Mars orbit. An ESA spacecraft will capture the sample container high above the Red Planet and return it to Earth.
However, the lander, the Mars rocket and the ESA orbiter will only be launched in the period 2027-2028. Persistence is healthy, but there’s no guarantee the six-wheeled robot will still be operational when the sample-return hardware reaches the Red Planet. So, the mission team members created a backup delivery schedule, and that’s where the Three Forks Depot comes in.
The sample return lander will carry two helicopters similar to Ingenuity, the small helicopter that flew to Mars with Perseverance and is currently serving as a scout for the rover. These future rotorcraft will ferry Perseverance samples from the depot back to the lander if the rover isn’t up to the task.
The sampling helicopters can only carry one tube at a time, so Perseverance’s depot drop needs to be designed accordingly.
“Until now, all that was required for Mars missions was a good landing zone; we need 11,” said Richard Cook, Mars Sample Return Program Manager at NASA’s Jet Propulsion Laboratory (JPL) in Southern California, in Friday’s update.
“The first is for the Sample Retrieval Lander, but then we need 10 more nearby for our Sample Recovery Helicopters to take off and land and also drive,” he added.
Perseverance will therefore drop its tubes in a zigzag pattern onto the red dirt at Three Forks, each 16 feet to 49 feet (5 to 15 meters) from its nearest neighbor, NASA officials said.
Related: The Mars Sample Return mission adds 2 helicopters and a rover for scrap pickup
Another major milestone is also approaching for the Perseverance team – the end of the rover’s main mission. That will happen on January 6, which is one Martian year (about 687 Earth days) after its landing on February 18, 2021.
But don’t worry: Perseverance will then roll on on an extended mission that should see the rover explore some exciting and intriguing locations.
“We’ll still be working on delivering the sample repository when our expanded mission begins on January 7, so that perspective doesn’t change,” Art Thompson, project manager of Perseverance at JPL, said in Friday’s update. “But once the table is set at Three Forks, we’ll be making our way to the top of the delta. The science team wants to take a good look around up there.”
This “Delta Top Campaign” is expected to start in February and last about eight months. During this time, the mission team will search for stones that were carried to Jezero by the river that flowed there long ago.
“The Delta Top campaign is our opportunity to take a look at the geological process beyond the walls of Jezero Crater,” said Katie Stack Morgan, associate project scientist for Perseverance at JPL, in Friday’s update.
“Billions of years ago, a torrential river carried debris and boulders miles beyond the walls of Jezero,” she added. “We will explore these ancient river deposits and obtain samples of their well-travelled boulders and rocks.”
Mike Wall is the author of “Out there (opens in new tab)(Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for extraterrestrial life. Follow him on Twitter @michaelwall (opens in new tab). Follow us on Twitter @spacedotcom (opens in new tab) or on Facebook (opens in new tab).
https://www.space.com/nasa-mars-rover-perseverance-set-cache-first-sample Perseverance Mars rover to begin caching samples