NASA Glenn developing new instruments to search for life on Mars

Michael Cole

GLENN RESEARCH CENTER, Ohio — One of NASA’s future Mars rovers may be able to search for evidence of life on Mars like never before. A new suite of instruments is currently under development through a joint effort between the NASA Glenn Research Center and the University of Michigan. It is called MAHRS – Martian Aqueous Habitat Reconnaissance Suite.

As its name suggests, the instruments are designed to investigate areas where water is present – in this case, the wet brine environments in the shallow subsurface of Mars.

The MAHRS instrument suite includes an optical microscope, a radiometer, a saltation probe, a soil wetness sensor, and an electric field sensor. A great deal of the work on the instruments is being done by a group of NASA Glenn project engineers with much experience in the development of instruments for previous probes and rovers to Mars and other planets.

Nilton Renno, a professor of Climate and Space Sciences and Engineering at the University of Michigan, had ideas for how the NASA Glenn team’s experience could be applied toward developing instruments for a more focused search for evidence of life on Mars.

“Nilton came here one summer and looked at what we had done in the past for previous missions, hoping to be able to apply that to future NASA research announcement calls,” NASA Glenn Senior Research Engineer Mike Krasowski told SpaceFlight Insider.

Renno and NASA Glenn researchers wrote two proposals together. The first was for a soil wetness sensor, and the other an electrical field sensor.

“We worked on those two things, and got funds to mature those two instruments,” Renno told SpaceFlight Insider.

Shortly thereafter, NASA started the MatISSE program – Maturation of Instruments for Solar System Exploration. Its goal was to develop planetary and astrobiology instruments that could be proposed in response to announcements of flight opportunity, without extensive additional technology readiness development.

“When the MATISSE program started,” Renno said, “people told me here is a new opportunity. That is when I came up with the concept of putting all the instruments together in a suite that would focus on habitability.”

Renno and NASA Glenn engineers decided to come up with an instrument suite that would help a future Mars mission decide where to look for evidence of life. With a moving rover, the places they would want to look at would be areas with water or liquid brine, since all life we know on Earth needs water.

“Another condition is a place where there is a continuous replacement of materials,” Renno said, “so that there are nutrients that would be moving the soil around by a process we call saltation.”

The third condition of searching for life is to find places protected from radiation or energetic particles from outside the planet. The shallow subsurface of Mars would be so protected.

“The suite of instruments we developed are designed to investigate these kinds of areas,” Renno said.

The optical microscope is designed to study the size and characteristics of settling dust on Mars. The microscope lens is turned upward, thereby allowing Martian dust to settle on the settling glass where the lens can take high-resolution images of the settled particles. The instrument is a 4-inch × 4-inch (10 cm × 10 cm) cube equipped with a sensor, a circuit board, and the microscope.

A radiometer mounted to the microscope measures the amount of solar energy absorbed at the surface. The less solar energy observed at the surface means more dust in the Martian atmosphere is absorbing the energy.

The third instrument is a saltation sensor. Even NASA Glenn engineers did not know what saltation was when Renno proposed an instrument to detect it.

“We had to look it up,” Krasowski admitted.

Saltation, essentially, is the process of small particles of dust or sand bouncing or skipping along the surface. In searching for evidence of life on Mars, it is important to understand how this process works on the planet’s surface.

“Some dust goes right up into the air, and that’s what the microscope is going to image as it falls back down,” Krasowski said. “But other stuff just sort of skips across the surface and takes off. The astrobiology people figure that is a primary transport mechanism for organic materials. That’s how seeds and other organics move around on the planet here.”

Since it will observe the movement of particles close to the surface, the saltation probe would hang low from the bottom of a rover. It will look at the habitability of the Martian surface, observing the Martian dust and how it moves, an important factor to knowing what kind of biological processes might be supportable on Mars.

“We have four faces on the sensor,” NASA Glenn engineer Larry Greer told Spaceflight Insider. “Those enable us to determine the particle flow and direction as the particles impact on the sensor. We can also determine the amount of impacts we get and the energy of the impacts.”

The saltation probe and microscope together will help inform astrobiologists what mineral contents are there to support biological processes.

NASA Glenn’s partnership with the University of Michigan also developed the soil wetness sensor, which measures the water content on the surface and detects the formation of liquid brines.

University of Michigan engineers are also testing an electrical field sensor to measure electrical charges in the Martian atmosphere caused by airborne dust. It will take these measurements from its place at the end of a rover arm. It will observe weather patterns and, together with its measurements of airborne dust, will reveal more about the level of erosion on Mars.

“We wanted to enhance existing instruments and integrate them into a suite that will look at the habitability of the Mars surface, particularly dust and how it moves,” NASA Glenn project engineer Norman Prokop told SpaceFlight Insider. “The researchers particularly want to know what kind of biological processes might be supportable on Mars. What mineral contents are there to support biological processes.”

The MAHRS suite of instruments has not yet been tapped for inclusion aboard any of the upcoming Mars missions. But that could change at any time, and NASA Glenn engineers are positioning the suite to be ready and adaptable for upcoming missions. The instruments will be ready to engage in their specific approach to the search for life on Mars.

“It’s geology and astrobiology and how they intersect,” Krasowski said. “There’s a close connection between the astrobiologists and the geologists, and with these Mars missions you see a lot of that because Mars now appears to have some surface water that goes through state changes, and we need to prove that. And that is part of what this set of instruments is all about.”