The researchers analyzed lunar rock samples sent back by the Chinese Chang’E-5 lunar lander and found that they had traces of water. The results were published in the journal temper nature.
Chang’E was sent to the moon in December of 2020, collecting samples of rock and soil from the lunar surface. Spectroscopic analysis on board confirmed the presence of water in real time in the samples. Two days later, a rocket was launched from the moon with these samples and fell to Earth two weeks later. Researchers have been studying these samples in more detail and now have found evidence of water in them.
But is it moon water?
When analyzing rocks and soils, the researchers found that the samples, on average, contain 30 parts of hydroxyl per million. Hydroxyl is the name given to a molecule containing one atom of hydrogen – often one atom of oxygen as a result of water reacting with some substance.
Researcher Parvathi Prem, who was not involved in the research, said new world The amount of water found during this mission was less than expected. The fact that the samples were taken at a time when the moon’s temperatures were close to 200aP (93ac) He may also have contributed to this.
Scientists wanted to confirm that the water on the surface actually belonged to the moon. The solar wind also contains hydrogen molecules that can combine with oxygen at the surface to form water molecules. Such particles are usually found in glass structures and have also been found during previous missions to the moon, such as Apollo 11. They were tested in the early 2000s, according to a press release from the Chinese Academy of Sciences.
The researchers took this into account and collected samples at a time when the solar wind was low. The impact of this decision was evident when Chang’E collected samples containing only a third of these glass structures compared to the Apollo 11 mission. The bulk of the hydroxyl molecules were found in a phosphate-rich mineral called apatite, which is found naturally on the Moon as well as on Earth. It is interesting that the apatite crystals contained up to 179 ppm water content, new world said in her report.
“This excess hydroxyl is local, indicating the presence of inland water from the Moon in the Chang’E-5 lunar samples, and that water played an important role in the formation and crystallization of late lunar basaltic magma,” Li Chunlai, the interview and study author said in a press release.
What does that mean for future lunar missions?
While the presence of water is great news, it’s not as if we’ve found a subterranean spring that supports human settlement in the near future. However, it does provide information that can be used to estimate water signals in future remote sensing survey data.
China’s subsequent lunar missions called Chang’E 6 and Chang’E 7 will use a combination of remote sensing and on-site and laboratory testing to better understand the source and distribution of lunar water.
“By investigating lunar water and its source, we learn more about the formation and evolution of not only the moon itself, but also the solar system,” Li added.
The range of distribution, time-varying properties, and sources of lunar water are still a matter of debate. We show here the spectroscopic observations of Chang’E-5 in situ for lunar water under the Earth’s magnetosphere and relatively high temperatures. Our results show that the hydroxyl contents of the lunar soil at the Chang’E-5 landing site have an average value of 28.5 ppm, which is the weak end of the lunar wetting properties. This is consistent with the predictions of remote sensing and ground-based telescopic data. In vitro analysis of returned Chang’E-5 samples also provides important clues to possible sources of these hydroxyl contents. Less polished glass contents indicate a weak contribution of solar wind implantation. Besides, the apatite in the samples can provide hydroxyl contents in the range of 0 to 179 ± 13 ppm, which indicates that the hydroxyl-containing apatite may be an important source of the excess hydroxyl observed in this small region of the mare.