You wouldn’t really be wrong if you said that the Moon is just a desert of gray dust, cold and mostly still. However, in a few months, small flickering lights will disrupt the darkness of one of our satellite’s craters. The baptized mission “Flammability of Materials on the Moon” (FM2, “flammability of materials on the Moon”) will be the very first attempt at controlled ignition on a celestial body other than the Earth.
The project, which may seem counterintuitive when we know the fear and danger posed by fires in a pressurized environment, in fact responds directly to this security emergency, because we do not know how fire behaves under low gravity.
The problem is relatively simple: on Earth we are protected by 1g gravity. When a candle burns, hot air rises and cool air (laden with oxygen) sinks, feeding the flame. This is natural convection. But on the Moon, where gravity is six times less strong, this gas exchange is completely disrupted. As NASA explains in its report presented at the 2026 Lunar and Planetary Science Conference, certain materials deemed safe on our Earth could become real time bombs once installed in a lunar base.
Until now, engineers were content with tests carried out in free fall towers or on board planes performing parabolas to briefly recreate microgravity. But these simulations only last a few seconds, far too few to observe the complete development of a fire. British online media IFLScience reports that researchers have even attempted to use centrifuges on the International Space Station (ISS) to simulate lunar gravity, with little success. To get a clear answer, there is only one solution: go burn things on the Moon.
The Mir trauma
NASA also highlights a fascinating point: “Consider a material that is marginally nonflammable on Earth. The same material may be flammable at a lower gravity level (e.g., on the Moon) because the crucial mechanism of oxygen entrainment by buoyancy at the base of the flame is still present, but at a slower rate, allowing chemical reaction rates to keep pace.” Basically, fire takes its time, but sometimes it takes place where it would have gone out on Earth.
This scientific curiosity is not just an exercise for physicists. It is based on a painful collective memory within space agencies. In February 1997, aboard the Russian Mir station, an oxygen generator caught fire, transforming the module into a tunnel of opaque, toxic smoke. European astronaut Reinhold Ewald remembers that “the fire was so huge and the smoke and steam coming from it was such that we could not see at arm’s length, and I could not imagine at that time that we would continue the mission”.
The FM2 mission will therefore use four samples of solid fuels. High-definition cameras will examine the flame, its color, its temperature and the way it spreads. This data will make it possible to adjust construction standards for future homes for NASA’s Artemis space program. Because if we want humanity to settle permanently on the Moon, we must first ensure that our walls will not turn into a spectacle for arsonists at the first short circuit.
Beyond immediate safety, this research opens the way to a better understanding of the physics of fluids. By observing how heat circulates in a 0.16 g environment, scientists also hope to improve the heating and ventilation systems of spacecraft.
Our presence on the Moon is discreetly changing its nature. We are no longer just visitors who plant a flag and leave with a few stones. Humanity is beginning to transform the Moon into a life-size laboratory, with the idea of establishing a base there in mind, before looking further afield.
