Engineers explore Moon regolith for sustainable landing pad construction

Building landing infrastructure on the Moon requires the use of local materials, as transporting large quantities of construction materials from Earth is cost-prohibitive.

Engineers are studying lunar regolith to determine how it can support the construction of landing pads capable of handling rockets such as Starship.

According to a paper published in Acta Astronautica by Shirley Dyke and her team at Purdue University, a landing pad must withstand mechanical stresses from rocket landings and ascents, as well as extreme thermal cycles of the lunar environment.

Early in-situ testing and data collection are critical to confirm the mechanical and thermal properties of the regolith before full-scale construction can proceed.

Importance of a Lunar Landing Pad

Landing rockets directly on lunar soil generates high-velocity plumes that can displace regolith and damage surrounding structures.

Existing Earth landing pads provide a controlled surface that reduces the risk of debris damage, but similar designs cannot be replicated on the Moon using Earth materials.

According to Dyke, sintering regolith to create a cohesive structure is the preferred method.

Sintering is a process in which the regolith particles are heated to the extent that they merge, turning into a slab that can withstand the stresses occurring due to rocket operations.

One of the main factors that influence the thickness of the pad is the strength of the material, which can be measured in terms of its compressive strength and tension resistance.

In addition, the pad has to control dust ejection when rockets land and take off, so that the nearby equipment and instruments are not bothered by dust.

Mechanical and Thermal Considerations

Mechanical testing of lunar regolith is limited, and simulants cannot fully replicate all lunar conditions. Dyke notes that in-situ testing on the Moon is necessary to obtain accurate measurements.

Thermal behavior also affects pad integrity. The lunar day-night cycle produces extreme temperature fluctuations that cause expansion and contraction in the pad material.

These variations interact with the loose underlying regolith and can produce warping stresses, potentially leading to fracturing or spalling.

For a 50-ton lander, Dyke’s team estimates a pad thickness of approximately 0.33 meters to balance structural integrity with thermal stress management.

Testing and Robotic Construction

The first lunar landing pads will likely be tested in situ before being used for repeated operations. Early missions may focus on collecting data about the regolith’s mechanical and thermal properties under lunar gravity.

Monitoring pad deformation under load and temperature changes can help refine design models and predict cracking patterns.

Construction and maintenance of the pad will primarily involve robotic systems. Teleoperated or fully autonomous robots are preferred, as human labor in space suits is not feasible for large-scale construction tasks.

NASA and commercial partnerships

NASA has initiated partnerships with commercial entities to develop lunar construction technologies.

ICON, a company specializing in in-situ resource utilization and 3D printing, has a six-year, $57.2 million contract to develop landing pads using local materials.

Their Olympus 3D printing system has been previously demonstrated in NASA experiments, including the 3D printed habitat challenge and CHAPEA analog missions.

The Moon to Mars Planetary Autonomous Construction Technologies program will oversee the project, supporting the development of landing and takeoff infrastructure on the lunar surface.

ICON’s work aims to validate the feasibility of constructing functional lunar landing pads entirely from available site materials.

Data from early testing and iterative construction will inform ongoing design improvements.

Dyke’s research and NASA’s partnerships provide a framework for sustainable lunar infrastructure that can accommodate repeated rocket operations while utilizing in-situ regolith efficiently.

Stay tuned for more updates.