How Sierra Space Aims to Produce Oxygen for Lunar Colonization

This article details Sierra Space’s ongoing research into creating oxygen on the moon, outlining the challenges and breakthrough technologies that may support sustainable human presence on the lunar surface.

Sierra Space is developing a groundbreaking device aimed at producing oxygen under conditions mimicking those found on the moon. In a large spherical chamber, engineers operated a complex machine designed to process lunar-like regolith, a blend of dust and sharp particles similar to actual lunar soil. Through controlled experiments, the team is looking to extract oxygen from the regolith by heating it to over 1,650 degrees Celsius, prompting oxygenated molecules to be released.

Brant White, a program manager at Sierra Space, emphasized the significance of this technology, stating, "We’ve tested everything we can on Earth now. The next step is going to the moon." This experiment took place at NASA’s Johnson Space Center, among numerous other initiatives aimed at enabling a sustained human presence on the moon. As astronauts may require oxygen not only for breathing but also for propulsion fuel for future missions to Mars, research on lunar resource creation is crucial.

The utilization of lunar regolith offers rich possibilities, as it contains metal oxides which can potentially be processed to extract oxygen. Although the principles of oxygen extraction through metal oxides are well-established on Earth, replicating this process in the varying conditions on the moon presents considerable challenges. The spherical chamber utilized by Sierra Space simulates the moon's vacuum, temperature, and pressure conditions, while also accommodating the regolith's abrasive nature, which can wear out sensitive machinery.

One significant hurdle remains the lower gravitational pull of the moon, about one-sixth that of Earth. As Paul Burke from Johns Hopkins University outlined in a recent study, certain extraction methods, such as molten regolith electrolysis, could be affected by this reduced gravity. His research indicates that while oxygen bubbles formed in the regolith may not detach as easily due to its viscous properties, potential solutions like vibration or smoother electrode surfaces could facilitate the extraction process.

In contrast, Sierra Space’s technology employs a carbothermal method that allows oxygen bubbles to form freely in the regolith, reducing the likelihood of interference during extraction. Burke estimates that each astronaut would need an equivalent of two to three kilograms of oxygen daily, although life support systems would likely recycle breathable air, streamlining oxygen processing needs.

Sierra Space’s technology requires some additional carbon input but is built to recycle most of it after each operation. Similarly, research by a group led by Palak Patel at MIT focuses on extracting both oxygen and metal resources from lunar regolith. To combat extraction challenges posed by low gravity, they introduced a novel “sonicator” to effectively dislodge bubbles using sound waves.

According to Patel's team, the results could yield vital materials such as iron, titanium, or lithium, aiding in on-site manufacturing of tools, spare parts, and construction materials, potentially fostering a sustainable human outpost on the moon. Through additional experiments, they have also explored converting regolith into strong, glass-like bricks that could be utilized for lunar architecture.

Overall, the ongoing research and innovation in oxygen extraction and resource utilization on the moon is critical for establishing a long-term human foothold beyond Earth, supporting ambitions for future interplanetary exploration.