Dispose of water on the moon without the need to transport it from Earth and in sufficient quantity to supply future human colonies that will populate the satellite in the coming years. That is the great benefit that emerges from the two studies published this Monday by NASA and that can represent a substantial advance in the conquest of space.
The data, this time, they leave no room for doubt. According to the studies revealed by the US space agency after more than two years of analysis, the Moon contains ice water and on its surface there are numerous craters of very different sizes that are never sunlight. In these places, NASA stresses, it could be trapped in a stable way and be much more accessible for future missions.
In this sense, the first of the studies – carried out by the SOFIA telescope (Stratospheric Observatory of Infrared Astronomy) – points out the unequivocal detection of molecular water (H20) on the satellite in both shaded and illuminated areas. Meanwhile, the second – carried out with data from NASA’s Lunar Reconnaissance Orbiter – suggests that some 40,000 square kilometers of its surface, of which 60% are in the south, have the capacity to retain water in calls. ‘cold traps’.
This finding represents a substantial step forward, since so far the data they were not conclusive. When the first astronauts to set foot on the Moon returned to Earth in 1969, all indications were that the satellite was a completely dry place, a belief that has changed over time and with successive discoveries. In fact, a couple of years ago signs of hydration had already been detected on the surface of the satellite, especially around the South Pole, but the analysis method used could not differentiate whether it was molecular water (H2O) or hydroxyl ( in the form of silicates).
How has this discovery been made?
The first of the findings, that of the unequivocal presence of water, is the result of a curious montage: a NASA telescope boarded aboard a Boeing 747 that flies at an altitude of 12,000 meters, with the aim of capturing infrared light at a wavelength that only water can emit. This system, explains René Duffard, senior scientist specializing in asteroids and surfaces of objects in the Solar System at the Institute of Astrophysics of Andalusia (IAA), makes it possible to discard all the water vapor from the Earth’s atmosphere.
The data was taken by SOFIA from Clavius crater, near the South Pole, at a wavelength of six microns, at which molecular water produces a unique spectral signature. This observation clear the doubts and banishes the possibility that it is hydroxyls.
The second discovery, Duffard explains, comes from an experiment that analyzes images from probes that have orbited the Moon and, in great detail, have calculated where there is a permanent shadow on the satellite. Thus, they have elaborated a map of where there could be stably frozen water, “as if it were a kind of snowfield”.
“In ‘cold traps’ the temperatures are so low that the ice would behave like a rock“, details Paul Hayne, from the University of Colorado Boulder and leader of the study, in such a way that if the water enters there” it will not go anywhere for a billion years. “These places, NASA deepens, can be very large. different: most of the time they are not more than one cent of a euro, while others can be several kilometers.
How much water is there?
Researchers estimate that the abundance in high southern latitudes is 100 to 412 grams of H2O per ton of regolith (the material from which the lunar surface is made) and the distribution in that small latitude range is the result of local geology and “probably not a global phenomenon.” It is an amount much smaller than on Earth, because the Sahara desert contains a hundred times that number.
The authors consider that approximately 40,000 square kilometers of the lunar surface it has the ability to trap water in these ‘cold traps’, especially at the North and South poles, which is almost double what has been planned so far. However, the only way to verify that they contain ice reserves is to “go there in person or with rovers and dig,” Hayne adds.
How will it affect future missions?
This finding, according to NASA and Duffard agrees, may have a notable influence on the development of future colonies to settle on the Moon. The US space agency plans to send a new mission to the satellite in 2024, known as the Artemis program, and the possibility of extracting water from its surface without having to transport it from Earth represents an “incredible advance”, according to the IAA scientist.
And now that? “You would have to know how much water is in each place, to determine where to go to look for it. Thus, you could identify the most accessible and cheapest placesin terms of energy and money, “says Duffard.
“If we are right, the water will be more accessible”, Hayne has stressed in the face of the establishment of lunar bases, which represent a necessary intermediate step for the arrival of human beings on Mars, in which NASA works and for which there is still no date. Having a map of the ice reservoirs on the Moon would make it possible to optimize living conditions on the satellite and bring the goal of reaching the Red Planet closer.