Mustafa Aksoy isn't likely to personally go to the moon. When astronauts, however, return to the lunar surface as part of the ambitious Artemis missions led by NASA, the kind of research Aksoy does will help play a critical role in establishing a permanent base on the moon and setting the stage for human explorations to Mars.

“Space exploration is our new age of discovery. What our ancestors were doing 400, 500 years ago, we are doing similar things on a much bigger scale,” says Aksoy, an assistant professor in the Department of Electrical and Computer Engineering in the University at Albany's College of Nanotechnology, Science, and Engineering.  

“Even as an elementary school student, I was interested in science and technology and history. I loved learning about the Age of Discovery, when European explorers circumnavigated the globe,” recalls Aksoy who grew up in Ankara, the capital city of his home country of Turkey.  

His imagination ignited, Aksoy charted his own course of exploration that led him to a science high school and then to Bilkent University, a selective private university in Turkey, where he studied electrical engineering and learned about the latest space exploration technologies. These fields became his passion, but “unfortunately, Turkey could not offer too much” in this area, says Aksoy and so he set off to The Ohio State University for graduate school and eventually landed at UAlbany.

“The work we’re doing at UAlbany in remote sensing is part of this new age [of exploration], and it’s at the intersection of my interests since my youth,” he says. Remote sensing is the process of detecting and monitoring the physical characteristics of an area — the moon's surface or glacial ice on Earth — by measuring its reflected and emitted radiation at a distance, typically from satellites or aircraft.

“Many, many remote sensing missions are currently probing different celestial bodies — the moon, Mercury, Venus, asteroids, etc. — to understand the formation and evolution of the universe, discover habitable lands in space and locate critical resources to boost human activity on the earth and initiate and sustain human presence in deep space,” says Aksoy, who worked on a large NASA mission designed to measure and map soil moisture across the planet. It was called Soil Moisture Active Passive, or SMAP, and was his first project in the area of remote sensing. Today, his remote-sensing research has two primary targets: our polar regions, mainly Antarctic and Greenland ice sheets, and the moon.

Ice, Ice Baby

“Understanding the dynamics of earth’s ice sheets (the cryosphere) is important for prediction of global climate, ice coverage and sea level rise,” says Aksoy. For the most part, this understanding relies on on-site visits by research teams to gather data about the density and temperature of ice and its crystal size.  

This on-location approach is both costly and geographically constrained to a small area, such as where a bore hole is dug. By contrast, remote sensing from space offers the possibility of larger-scale measurements with less environmental disruption by humans.

With his research, Aksoy seeks to answer the question of whether key parameters of ice sheets can be measured using microwave radiometers, which are sensitive receivers usually deployed on satellites. He was awarded nearly $500,000 through the National Science Foundation (NSF) Faculty Early Career Development Program to support this work. The project is downloading radiation data from microwave receivers on polar-orbiting weather-related satellites and using radiation models developed at UAlbany to estimate ice properties.

“We’ve actually demonstrated that it is possible to measure ice sheet parameters through remote sensing,” says Aksoy. “Moving forward, we’ll see if we need to change our models and we’ll seek to expand our studies to a larger scale.”

Moon Make-up

Given his love of exploration, it is not surprising that Aksoy finds the moon an even more interesting target.

His focus is on the regolith covering the moon’s surface. Lunar regolith is “a very fragmented rock, like beach sand, like glassy sand. Its thickness might change from a few meters to a few tens of meters,” says Aksoy, who did a postdoctoral fellowship at NASA’s Goddard Space Flight Center. The James Webb Space Telescope, one of the best-known instruments exploring deep space, was being built while he was there.

As with ice sheets, the question is whether microwave radiometry can characterize regolith properties. Understanding the regolith density, for example, is critical in selecting landing sites for NASA's Artemis astronauts and in discovering water ice resources locked within the lunar landscape. That water ice, according to a NASA video, is a "game-changing resource that can be mined to produce propellant and breathable oxygen for future explorers."  

“We know from previous lunar missions that water ice is captured in regolith, especially in permanently shadowed regions. That’s why the Artemis mission is targeting the moon’s south pole as a landing station. There are a lot of permanently shadowed regions there where water can be extracted,” says Aksoy.

By contrast with his cryosphere work, available regolith data is very limited. There are not yet research stations on the moon nor people regularly making measurements. The Chinese Chang E-1 and Chang E-2 lunar orbiters carried microwave radiometers between 2007 and 2011.  

“We were able to download that data and compare our estimations to measurements from the Apollo sites. We had a good match so it’s a promising sign that our radiation model is working,” he says. “We hope that when the Artemis mission sends people to the moon, they can do measurements that can validate our remote sensing efforts to characterize lunar regolith.”

For researchers like Aksoy, new technologies like CubeSats, miniature box-shaped satellites measuring slightly larger than a Rubik's Cube, are increasingly playing a major role in space exploration.  

“The future of remote sensing is constellations of CubeSats due to their low cost, small size and reduced power requirements, as well as their ability to provide frequent, real-time, consistent observations with large coverage,” says Aksoy. While there are many advantages, CubeSats also have some drawbacks. “These small systems are not as stable and accurate as big satellites and very susceptible to ambient conditions,” he explains. In a project funded by NASA, Aksoy works to facilitate measurement sharing among constellation members to minimize the uncertainties and errors in their measurements.

As CubeSat technology and other space technologies improve, Aksoy sees a universe of opportunities unfolding for today's students.

“This is a very hot field. It’s a strategic field. We need scientists and engineers working on these projects," he says. He hopes that his teaching and research at UAlbany helps ignite the curiosities and passions of a new generation, who, like explorers of old, will look up at the night sky and be inspired to see how far they can go.