The strategy has three “co-equal” science themes, said Becky McCauley Rench, program scientist in NASA’s planetary science division and co-lead of the study. One, called “exploring the potential for Martian life,” is focused on looking for any evidence of life on Mars. “Did life ever arise on Mars, and if so, does it exist today?” she said. “If life never developed, why not?”

A second theme, “supporting the human exploration of Mars,” is looking at the “synergistic observations” that could be made with robotic missions ahead of the first crewed missions, including key knowledge gaps to fill. “How can we prepare to maximize that precious human time on the surface and the resources in connection with the export community here on Earth?” she said.

The third theme, called “revealing Mars as a dynamic planetary system,” includes other science topics, with an emphasis on comparative planetology. “We want to learn as much about Mars as we know about Earth,” she said.

To perform the science in those three themes, the plan advocates a regular series of mission, focusing on smaller spacecraft. “This program is looking at changing the paradigm of how we think about Mars missions,” Ianson said. “Every opportunity there is when a launch window opens up, can we send something up?”