Is there water on the moon?

Whether there is water on the moon is related to the benefits and prospects of human development and utilization of the moon. Therefore. Whether there is water on the moon and how much water is available is not only a subject for scientists to study, but also a matter of great concern to aerospace experts. As early as several decades ago, scientists made various theoretical analyses and speculations on whether there was water ice on the moon. Astronomers believe that billions of years ago, comets and asteroids collided with the moon, leaving water there (the earth may also get water in this way). Water didn't stay on the moon for a long time. Due to the irradiation of the sun, water evaporates and goes into space. Only in the shadow of the deep Leng Yue pit can there be water, which is frozen and hidden there. However, since the 1960s, more than 50 lunar wipers launched by the former Soviet Union and the United States have never found any signs of water and ice on the moon. It was not until 1996 that American scientists discovered for the first time that there might be water ice in the low-lying area of the South Pole of the moon when analyzing the pictures and detection data sent back by the Clementine probe in 1994, and speculated that it might be the result of a comet impact 3.6 billion years ago, which was formed by the condensation of water contained in the comet on the surface of the moon. Later, the United States launched the "Moon Explorer" detector. The detector is equipped with a neutron spectrometer, which has high sensitivity and can measure the humidity of 1 cubic meter of lunar soil with only one cylinder of water. 1On March 5, 998, the Lewis Research Center of NASA released the first batch of lunar exploration results obtained by lunar explorers to the press, which confirmed the existence of water ice on the moon. The preliminary detection results show that water ice exists not only in the south pole of the moon, but also in the north pole of the moon. There are twice as many water ice in the Arctic as in the Antarctic. It is preliminarily estimated that the total reserves of water on the surface of the moon may be between the 6th power ton of1×10 and the 8th power ton of 3.3x10. If there is water ice there, NASA will send a remote-controlled satellite to the moon. The United States plans to launch the Lunar Reconnaissance Satellite (LRO) in 2008, which will orbit the moon for one year or more. The LRO is equipped with six different scientific instruments, which can draw more detailed maps of the lunar environment than previous lunar probes. Gordon Chen, a scientist in the LRO project of NASA Goddard Space Flight Center, said: "This is the first mission of a series of lunar exploration missions, and more probes will be sent to the moon every year, about 65,438+0, in order to prepare people for landing on the moon." The United States plans to send a man to the moon in 2020. LRO's instruments will do many things: they will draw and photograph the lunar terrain in detail, collect samples of the lunar radiation environment, and look for water on the moon. For example, the satellite's Lyman-Alpha Mapping Project (LAMP) aims to find the ice in the shadow of the lunar polar crater. How does LAMP explore in the dark? It is realized by the reflection of the sun's light. LAMP has the ability to identify ultraviolet wavelengths in a specific range. It can not only identify the strong light in this range, but also identify the hydrogen radiated through this range. The light sensor itself is luminous, so it can also see the objects around the moon pit. Water ice has a special spectral fingerprint under the same wavelength range of ultraviolet light, and we can prove whether there is water ice in the moon pit from its spectral characteristics. The plane is also equipped with a laser that can emit light into the dark moon pit. The name of this instrument is the lunar orbit laser altimeter (LOLA). Its main purpose is to draw a very accurate contour map of the whole moon, and also to measure the brightness of each reflected light. If there is water ice in the solid matter of the moon, even if its content is only 4%, its reflected wave will be very bright. Lola itself can't prove whether there is ice, and any kind of luminous crystal can produce brighter waves. However, if we only see bright waves in these dark craters, we can be sure that it is ice. There is an instrument called "fortune teller" in LRO, which can measure the temperature of the surface of the moon. In this way, the "fortune teller" can provide an "evidence" for other ice-sensitive measuring instruments of LRO, proving that there are no signs of freezing in those areas due to high temperature. Another way to identify whether there is ice is LRO's Lunar Exploration Neutron Detector (LEND), which can count neutrons ejected from the moon. Why can the moon emit neutrons? Its detection principle is that neutrons constantly escape from rocks and soil components under the bombardment of cosmic rays on the surface of the moon. If these neutrons have ever interacted with hydrogen, the main component of water, they have a specific energy level. The neutron spectrometer detects such neutrons, which is equivalent to detecting hydrogen, thus judging the existence of water. Now, Igor Vanov of the Space Research Institute of the Moscow Federal Space Agency is working on the development of LEND. Experts said: "The different tools of LRO should work well together. No instrument can provide evidence that there is ice on the moon. If all instruments prove that there is ice on the moon and there is ice in the same area, it will attract people's attention. " Experts also put forward another reason why water ice should be detected near the moon's poles: not far from some eternal dark moon pits are some permanently bright mountains, such as "the sun never sets its peak". In the future, the residence of the moon can be settled on these peaks, which can provide the solar energy needed by astronauts, while there is ice under the valley not far away, which can provide the water needed by astronauts. Some people disagree whether the water ice on the moon can be used as the water source for human beings after landing on the moon. Academician Ouyang Ziyuan of our country thinks that the water ice at the moon's poles can't be the water source for human landing on the moon at this stage. First of all, according to scientific inference, the most likely source of water ice on the moon is that when countless comets in the universe collided with the moon for billions of years, some water-containing debris fell to the low-lying area on the back of the moon where the sun could not be seen all the year round, thus existing in the form of water ice. Although the known water ice content on the moon far exceeds scientists' estimates, if the water ice is transported, melted and distilled on the moon for a long time until it is processed into a small amount of fresh water for human use, the project investment is much higher than that of directly taking water from the earth, and the water ice itself is a lunar resource that can never be regenerated. No matter from any aspect, the water ice on the moon can't be the water source of the current moon landing plan, even if. Is it wishful thinking or a scientific plan to use lunar water ice? The lunar reconnaissance satellite will give you the answer.