As NASA and private space companies prepare to return equipment—and ultimately astronauts—to the moon, they are confronted with an almost undetectable hazard to any future lunar outpost: microscopic dust particles. Regolith, or ground-up lunar rock, jams drills and other delicate devices and is so sharp that it damages spacesuits. Because dust absorbs sunlight, it can cause sensitive devices to overheat.
Dust particles are also hazardous to one’s health. Even though Apollo-era astronauts only spent a few days outdoors on each trip, several experienced burning eyes and congested nasal passages when they returned from lunar excursions and removed their dust-covered spacesuits inside the capsule. Images from the Apollo 17 mission, which focused on geology and included seven-hour excursions in the lunar rover, show astronaut Gene Cernan’s face coated in dust, as if he were some sort of outer space coal miner. Cernan informed NASA officials at a technical briefing after his return to Earth that lunar dust was nothing to be concerned about.
According to Phil Abel, manager of NASA’s Glenn Research Center’s Tribology and Mechanical Components Branch, the grit blocked the radiators that evacuated heat and carbon dioxide from spacesuits and wore a hole in Cernan’s outer spacesuit’s knee. (Tribology is the study of friction and wear.) According to a report from a NASA workshop on lunar dust in 2020, the Apollo 17 crew carried dust into the capsule, where it smelled like gunpowder and prompted lunar module pilot Harrison Schmitt to experience hay fever symptoms.
Lunar ice is mostly made up of water and trace quantities of other compounds, but it also contains moon dust. According to Roth, Off Planet creates its own filthy snowball simulant by freezing the components onto a standard simulant using a method known as cryogenic vapor deposition. Off Planet derives its frosty formula from pictures and other data collected by spacecraft circling the moon; its lunar ice simulant is a combination of water, carbon dioxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, methane, ethane, ammonia, and methanol, as well as the regolith.
The company has several dozen clients from ten nations, all of which are planning for their own eventual moon trips, and they require these mimicked materials to ensure that their equipment functions properly. According to Off Planet co-owner Vince Roux, blending artisanal moon dust is a “definitely a growing industry.” “The economic return now makes sense, and we intend to grow.”