WASHINGTON – While NASA has spent a decade trying to return samples from Mars, some scientists are concerned that the campaign may not provide funding for other robot missions on the planet.
The only future NASA mission for Mars under development is Mars 2020, a rover currently in final assembly scheduled to launch in July 2020. The rover is based on the Curiosity Rover, which has been on Mars for seven years, and will cache Martian rock and soil samples for later return to Earth.
While NASA has not formally committed to the additional missions required to retrieve and return the samples, both NASA and the European Space Agency have begun to plan it. This approach involves a NASA-led mission to land on Mars, take the samples and place them into orbit around the planet, and an ESA-led mission to bring the sample container into orbit and return to Earth , Both missions would start in 2026 and return the samples in 2031
However, as participants in a meeting of the Mars Exploration Program Analysis Group (MEPAG) last month in Pasadena, California, they discovered that there are virtually no other Mars robotic missions developed. The only exceptions are Escape and Plasma Acceleration and Dynamics Explorers (EscaPADE), a planned Smallsat mission to study the interaction of the solar wind with the Martian atmosphere that NASA selected in June as part of a new Smallsat program for planetary science. NASA is funding further studies on EscaPADE, but without guarantee that the mission will be approved for development and launch.
This has led to concern that the return of Mars samples is driving other research that scientists on Mars would like to undertake. "Our highest priority is the Mars sample return, but we also have other priorities," said R. Aileen Yingst, chair of MEPAG, at the beginning of the group's July 26 meeting. "We should address open scientific questions in parallel or as part of sample return. At the moment, there are no flight options that look into the future in this way.
She noted that, in addition to the lack of Mars missions of the flagship class such as Mars 2020, scientists have since been unable to suggest mid-sized New Frontiers missions while advertised are limited to only a handful of selected targets that exclude Mars for the time being , The smaller Discovery program, which also selects missions in a contest, can be used for Mars missions such as the InSight Lander. However, she said, "It's problematic to get to Mars below the ceiling of discovery costs."
"There is concern in the community that new data may not be available soon," she concluded.
Later During the meeting, scientists surveyed attending NASA officials for options to correct this, such as flying additional scientific instruments on the Sample Return Landing and Orbiter missions that were launched in 2026 Consider additional scientific payloads for these missions to fly at an early stage of their development. However, he argued that this did not fit into the "lean" Mars sample return architecture announced almost two years ago by Thomas Zurbuchen, NASA's Associate Science Administration, which sought to return samples as quickly and cheaply as possible.
"That was the right decision," he said. These pattern return missions face "very, very intense drive requirements" to get to and from Mars. "Every time I add an extra kilogram of mass, the problem becomes more and more difficult to implement."
Some asked about another orbiter to cope with communication with the surface and other roles, such as imaging, given the age of existing orbiters. Watzin said that by starting the other two parts of the 2026 sample-retrieval campaign there would be a "reasonable likelihood" that existing orbiters could at least function as communication relays.
Watzin was more pessimistic than an orbiter who wanted to do science. "Unfortunately, we live in a world of limited budgets," he said, acknowledging the need for a new remote sensing mission to support science and possibly human future exploration.
"Do I have a plan today? No," he said of a new orbiter.