NASA, ESA Change Course on Mars Sample Return

NASA and ESA announced a major change of plans today for the Mars Sample Return campaign. The two agencies will still work together to return the samples now being collected by NASA’s Perseverance rover, but Perseverance itself will transport the samples to their departure point for the trip back to Earth instead of an ESA rover. Not only that, but NASA will send two more helicopters to Mars to provide a backup method for retrieving the samples in case something goes awry with Perseverance. ESA still is providing the spacecraft to make the trip back to Earth and a robotic transfer arm.

Perseverance landed last year accompanied by the tiny Ingenuity helicopter, a technology demonstrator that has far exceeded expectations. Designed to make 5 test flights over the course of a month, it is now up to 29 flights and still going strong, scouting the terrain ahead of Perservance.

Thomas Zurbuchen, NASA Associate Administrator for the Science Mission Directorate, said during a media teleconference today that Perseverance and Ingenuity are performing so well that ESA’s Sample Fetch Rover is not necessary.

The plan had been for Perseverance to leave the cigar-shaped sample tubes on the surface as it roamed the planet. The ESA Fetch Rover would later collect them and take them to a NASA Mars Ascent Vehicle (MAV) that would launch them into orbit around Mars. An ESA spacecraft, the Earth Return Orbiter (ERO), would rendezvous with the MAV, the samples would be transferred into a NASA container — a Capture, Containment and Return System — on the ERO and head back to Earth. The container would separate from the ERO as it approached Earth and descend through the atmosphere to the surface.

That architecture required two landers, one for ESA’s rover and one for NASA’s MAV.

Zurbuchen said over the past year options have opened up that “frankly weren’t available to us” a year ago. Perseverance is operating so well that NASA now is “comfortable” that it will be capable of driving the samples to the MAV itself. He said it always was the backup to ESA’s rover, but now will be the primary vehicle.

Perseverance’s backup will be two new helicopters derived from Ingenuity that will be delivered by the NASA lander. They will have wheels and small arms to grab the sample tubes.

The NASA lander will be equipped with an ESA Sample Transfer Arm to transfer the samples from Perseverance and/or the helicopters into the MAV.

The announcement today comes after completion of the program’s Systems Requirement Review. Asked if this architecture will save money, Jeff Gramling, the head of NASA’s Mars Sample Return program, punted. He said one lander is cheaper than two, but NASA does not commit to cost or schedule until Key Decision Point-C, a milestone that won’t be reached for another year.

Launch of ESA’s Earth Return Orbiter with NASA’s container is scheduled for the fall of 2027. That would be followed in the summer of 2028 by launch of the NASA lander with the two helicopters, MAV and ESA Sample Transfer Arm. The samples would arrive back on Earth in 2033.

The change in plans is the second major perturbation for ESA’s Mars exploration plans this year. Russia’s invasion of Ukraine on February 24 upended European space cooperation with Russia including the planned launch this year of a Russian lander and ESA rover as part of the ExoMars program. ESA’s rover, named Rosalind Franklin, is already built and was about to be shipped to Russia for integration with the launch vehicle. ESA terminated its cooperation with Russia and now is in discussions with NASA about how it might be able to move forward with that rover. David Parker, ESA’s Director of Human and Robotic Exploration, said a decision on Rosalind Franklin is expected at an ESA Council meeting in November.

Asked if ESA was disappointed or relieved it no longer had to build the Sample Fetch Rover and now can focus on getting Rosalind Franklin to Mars, Parker said the engineer in him was fascinated by the Fetch Rover because it would have been able to travel much faster than previous rovers, but from a programmatic standpoint, the new plan makes sense.