Dr. Meenakshi Wadhwa, professor and Director of the School of Earth and Space Exploration at Arizona State University, spoke about the Mars Sample Return program at Whitaker Hall on Oct. 26. As the lead scientist for the program, Wadhwa gave insight into the motivations behind the program and the prospective timeline of retrieving samples from Mars.

Run by NASA (National Aeronautics and Space Administration) and ESA (European Space Agency), the goal of the Mars Sample Return program is to deliver samples collected by the Mars Perseverance rover to Earth for detailed analysis. The project will be significant for scientific understanding of Mars’ climate and research about the plausibility of life existing during the planet’s history. 

Wadhwa began her lecture explaining that while Mars is currently uninhabitable, it may have once been warmer and more hospitable. She introduced some of the questions her team is interested in pursuing. 

“What actually happened? How did that climate evolve?” Wadhwa said. “We want to understand that, and then certainly, of course, the potential for the development of life in that context.”

Wadhwa explained that NASA prioritized the Mars Sample Return program in their last decadal survey, which outlines NASA’s goals over ten years. 

“It basically said that Mars Sample Return is the highest scientific priority for NASA’s robotic exploration efforts,” Wadhwa said. “It has merit, you know, high significance.”

Wadhwa acknowledged that the process of analyzing the retrieved samples will be long and comprehensive, bringing together scientists across disciplines. 

“These return samples will be analyzed for many, many decades to come in laboratories across the world,” Wadhwa said. “The impact of that is going to be huge. There’s going to be biologists, there’s going to be geochemists, there’s going to be modelers, theorists — all kinds of scientists that are not even planetary scientists, but who will be interested in the samples that represent the very first samples from another planet that we will bring back here to study.”

As for the process of collecting these samples, the Mars Perseverance rover, launched in 2020, has already documented and collected many diverse samples of rocks, regolith, and data from the atmosphere. The current plan is that these samples will be delivered to a lander, launched, and captured by an orbiter that will carry the samples to Earth.

Scientists have strategically chosen which landing spots they want to collect from, hoping to obtain a broad range of samples.

“The big strategy was to try to really maximize the diversity of samples that we were collecting,” Wadhwa said. 

To collect diverse samples, Wadhwa said her team collected two of every rock they found. They kept one on board Perseverance and saved one to analyze. 

Wadhwa also discussed the timeline for future launches to perform sample collections. She said that there are two launches planned for either 2027 or 2028, but that they might be pushed back by a year or two. 

The scientists plan to target certain locations on Mars’ surface, specifically those that mimic habitable environments.

“The idea is to get a diversity of samples that are going to be helping us to address all of the science goals that I mentioned: to understand the geologic context, to understand the climate history, and to understand the history of whether there was ancient life,” Wadhwa said. 

According to Wadhwa, analyzing the materials on the surface of Mars will give scientists information about the interior of the planet, too. 

“If you can do geochronology, you can date the formation of these rocks,” Wadhwa said. “You can learn something about the composition of the magma from which this rock formed, and that also tells us about the interior composition of Mars.”

Wadhwa also showed the audience an animation that demonstrated how the machinery would execute the sampling and retrieval. The animation portrayed the entire process of launching the samples and bringing them to Earth. It is estimated that these samples will land in the Utah desert in the early 2030s.

Wadhwa ended by answering some questions from the audience and going into more detail about the design of the lander and the sampling tubes.

“It is a very complicated mission,” Wadhwa said. “It’s going to be a hard thing…there are going to be a number of firsts. But, you know, that’s where you make the biggest progress, it’s when you really push the envelope, and it’s going to be doing that in space, for sure.”