Research, Technology

Water on the moon: what Chinese lunar rover Chang'e-5 discovered

China's Chang'e-5 spacecraft arrived atMoon on December 1, 2020 and became the first device on the surface of the Moon to detect signs of water inside the rocks and soil of our satellite. The Chang'e-5 lunar mineralogical spectrometer used on-board instruments to make a series of scientific measurements, and from its fascinating journey brought over 60 ounces of soil and rock samples to our planet. While the probe was on the moon, researchers from the Institute of Geology and Geophysics of the Chinese Academy of Sciences speculated that the craft had detected water, namely H2O molecules. This discovery was made possible by the ability of the satellite to reflect and absorb the sun's rays. Interestingly, one of the main objectives of the mission was the desire of scientists to understand whether it is possible to use water on the Moon for astronauts who are away from the planet for a long time. The researchers also believe that future astronauts will be able to live on the Moon by extracting molecular oxygen and hydrogen to produce water and pure oxygen.

China's most difficult space operation successfully ended on December 17, when the return capsule of the Chang'e-5 lunar probe landed in the grasslands of northern China.

An analysis of the images taken by the Chang'e-5 apparatus confirmed the presence of water on the moon. Chang'e 5 is the first mission in 40 years to return samples of lunar soil to Earth.

How much water is on the moon?

In the late 2000s, a number of missions found signsthe presence of water on the surface of the moon illuminated by the sun, but scientists have not been able to prove its presence. And yet, over the past two decades, ice has been discovered in hard-to-reach craters around the satellite's poles, which are constantly in shadow.

Then, in November 2020, one month beforea Chinese lander detected water on its surface, NASA announced that it could indeed confirm the presence of water in the solar part of the moon without even going there. Using the SOFIA infrared observatory, physicists have been able to pick up signals from different wavelengths of water molecules.

Moreover, this discovery showed that water could be widespread on the Moon, and not just frozen at its poles.

Areas with water are marked in blue.

It is also interesting that Chang'e-5 became the first lunarmission to collect and return materials since 1976, when the Soviet Union's Luna-24 probe brought samples to Earth. The last time NASA extracted moon rocks was 50 years ago, in 1972, so today the whole world is watching the achievements of Chang'e-5.

More on the topic: Scientists studied the lunar soil mined by the Chang'e-5 apparatus. What new did they learn?

It is important to understand that water is a rare resource in deep space. And given that it's a vital ingredient,its scarcity outside of Earth represents a major obstacle for humans in space exploration. Previously it was believed that the surface of the moon is completely "dry", but in the last decade, scientists have confirmed the presence of water on its surface.

In search of H2O molecules

Research team from the Chinese AcademySci. saw signs of water in the probe data. Chang'e-5 identified H2O molecules based on their distinct spectral reflectance - a measurement of how objects reflect or absorb solar radiation. The work was published in the journal Science Advances.

The discovery of Chang'e-5 shows that on the moonbe more water than expected,” said Matt Sigler, a senior fellow at the Planetary Science Institute, a non-profit organization based in Arizona. Siegler himself will join NASA's Artemis team to drill ice at the moon's south pole.

This is the first expedition in 40 years to bring samples of lunar soil back to Earth.

Do you want to always be aware of the latest scientific discoveries? Subscribe to our channel in Telegram and join the comments!

In the past, moon rocks returned by missionsApollo were extremely dry, and it was assumed that the water got to the moon along with earthlings. However, previous measurements have shown the potential presence of water, but none of these studies have been done on the Moon itself—until now. The difference, the researchers say, is that the spectral reflectance data needs to be corrected for the temperature of the object. This is necessary to determine how much water is on the satellite.

Heat from the Moon's surface can change or mask the features of the reflected light. But determining the temperature of a target at a great distance is incredibly difficult, physicists say.

Of course, Chang'e-5 did not detect bubblingrivers or cascading waterfalls in a previously unexplored area. The researchers believe that the water most likely formed due to the solar wind. When the solar wind containing hydrogen atoms acts on the oxygen in the lunar soil and rocks, sometimes there is water.

The concentration of water on the Moon is approximately 120 grams for every ton of lunar soil, but a slightly higher concentration is observed in lunar rocks - 180 grams per ton.

Don't Miss: Why an Oxygen Catastrophe Occurred on Earth and How the Moon Affected It

Where does water come from on the moon?

Despite the fact that the descent vehicle foundthere was water on the satellite, there was not much of it. In some of the driest places on Earth, soil moisture typically ranges from 0.2 to 5 percent, the researchers found. According to the data obtained, there was about 0.018% water in the lunar rock, and only 0.012% in the nearby soil. It is clear that we would have to crush a lot of stones to get a glass of drinking water, but this is just the beginning.

Do you think we will ever be able to live on the moon?

According to scientists, in the future it will be requiredresearch on the water content in lunar rocks, and this will finally allow us to understand where the water on the Earth's satellite came from, even if it is very little. Today we know that the water in the soil of the moon was formed from hydrogen brought by the solar wind, but what is hidden on its dark side? And is there water there? We hope to have answers to these and other questions soon.