Drone radar could help spacecraft pinpoint where to drill for water on Mars, scientists say – Image for illustrative purposes only (Image credits: Unsplash)
Researchers trekked through mosquito-filled terrain in Alaska and boulder-strewn slopes in Wyoming to launch drones carrying ground-penetrating radar over debris-covered glaciers. The flights produced detailed maps of ice hidden beneath layers of rock, validating a technique that promises to guide spacecraft in selecting precise drilling locations on Mars. This Earth-based proof-of-concept addresses a key challenge for future missions: pinpointing accessible water ice amid uncertain surface cover.[1][2]
Mars’ Buried Ice Deposits Pose Drilling Dilemma
Glaciers on Mars lurk in mid-latitude regions, often shrouded by rocky debris from rockfalls, dust-filled craters, or valley accumulations. Orbiting spacecraft radars detect these ice volumes but fail to measure the thickness of overlying material or reveal internal structures. Such details matter greatly for missions aiming to extract water, as drilling through meters of rock could strain resources.[1]
“If you want to make decisions about where to drill on Mars, you need to know if the ice you’re trying to find is under one meter of debris or 10,” said Roberto Aguilar, a doctoral researcher at the University of Arizona Lunar and Planetary Laboratory and lead author of the study. These deposits hold potential as multi-use assets: sources of drinking water, oxygen for breathing and fuel, support for agriculture, and sites for probing ancient climates or signs of life. Recent findings indicate some Martian glaciers consist of more than 80 percent pure water ice, heightening the stakes for efficient access.[1]
Field Tests on Mars-Like Earth Glaciers
The University of Arizona team targeted two prime analogs: Sourdough Rock Glacier in Alaska’s Wrangell Mountains and Galena Creek Rock Glacier in Wyoming. These sites mimic Martian features, with ice insulated under sediment and rock that slows melting even in relatively warm climates. Fieldwork demanded preparation, from charging drone batteries via generators to carrying bear spray amid rugged hikes.[1]
Drones flew low over the surfaces, capturing radar signals that penetrated the debris. Researchers then validated the data through direct excavation and drilling, confirming matches in debris thickness. Simulations further ruled out interference from surface features like boulders or trees, ensuring signals reflected true subsurface ice. The effort marked the first application of drone-mounted radar to planetary glacier analogs.[2]
Refining Radar for High-Resolution Insights
Key optimizations emerged from the flights. Drones performed best at specific altitudes and speeds, with paths aligned along the glacier flow for optimal signal capture. Proper radar orientation proved essential to distinguish ice from rock. Unlike orbital instruments, the close-range flights yielded far sharper images, exposing not just debris depth but also ice purity and layered histories within.[1]
“The internal layers we’re seeing are important because they’re a record of past climate cycles,” Aguilar noted. Each stratum captured centuries or millennia of accumulation, a feature likely replicated on Mars. The technology’s portability suits planetary use, filling the resolution gap between distant orbiters and boots-on-the-ground sampling.[1]
Earth vs. Mars Radar Advantages
- Resolution: Drones image at higher detail due to low-altitude flights.
- Debris Mapping: Measures 1-10m thicknesses precisely on Earth analogs.
- Mars Edge: Dry soil enhances signal penetration over Earth’s wetter conditions.
Toward Deploying Drones on the Red Planet
The study, published in the Journal of Geophysical Research: Planets, establishes drone radar as reliable for scouting buried ice. On Mars, a thin atmosphere demands lighter designs like NASA’s Ingenuity helicopter, which logged 72 flights before rotor damage in 2021. Yet the radar’s lightweight profile fits proposed Mars Scientific Helicopter payloads, and drier regolith may even improve performance.[2]
“We are filling the gap between today’s orbital observations and a more distant future, where astronauts land on Mars and make observations on the ground,” Aguilar explained. This positions the tool as a precursor for human exploration, enabling smarter site selection before drills engage. Field hardships on Earth underscored the appeal: “It’s not fun walking on those rocks. That’s why it’s better to fly a drone.”[1]
With validated precision, drone radar stands ready to transform how missions approach Mars’ hidden water reserves, one flight at a time.