The American allegations have raised a lot of controversy about the falsity of the images coming from the Russian “Luna-3” probe after a successful flight in 1959, which was the first of its kind, as the space probe flew over the moon from the other side that our eyes had never seen before, so it was What the images revealed was a great shock, due to the stark contrast between both sides of the moon. The near side facing us, and the far side we cannot see.
The difference in the images between the two sides was very clear. The lava plains, which appear in the form of dark spots, spread on the opposite side of the moon, while they spread less on the other side, which is not visible. The images also show that the far side is more rugged than the near side, which sparked a fuse. Multiple questions.
The Luna-3 flight was not limited to bringing pictures of the moon, but it also opened the door to asking one of the most controversial questions among the great mysteries of science today, which is the secret of the difference between the far side of the moon and the near side.
Comparison between the far and near faces of the moon
In the film “The Far Side of the Moon,” which was presented by Al Jazeera Documentary as part of the “Great Mysteries of Science” series, we discuss the most famous theories that explain this difference, from the words of scientists and experts who have spent most of their lives solving this stubborn mystery.
“Apollo” samples...the difference in the chemical composition of the two faces of the moon
One of the oddities of the moons in the solar system - including our moon - is that they face the planets that revolve around them with one side, with the result that the near side always remains close, and the far side always remains far away. American planetary scientist Bill Hartman says that in 1959, the Russians surprised the world with unique pictures of the far side of the moon, which made everyone surprised by what was in those pictures, because they did not resemble the front side of the moon in any way.
American planetary scientist Bill Hartman
These images prompted more trips and investigations over the next few years, to search for the secret of that difference, and each new discovery was accompanied by an exciting fact that prompted more questions about the moon’s past and its ancient history.
At the end of the sixties of the last century, the first spacecraft carrying an astronaut landed on the surface of the moon, as part of the “Apollo Space Program,” in a historic achievement. The Apollo missions to the moon were not limited to conducting scientific experiments and bringing pictures, but the astronauts also brought with them lunar samples, which contributed to revealing important facts about the moon later.
Upon returning to Earth, the Apollo missions brought back 382 kg of dust, stones and samples from the Moon.
Upon its return to Earth, the Apollo missions brought 382 kg of dust, stones and samples from the moon. Scientist Jess Barnes from the University of Arizona - one of the few who studies these samples - says that these samples are subject to in-depth study, because analysis methods are constantly evolving. Thus, scientists can answer questions that were previously asked, and raise new questions as well.
Geologist Jess Barnes from the University of Arizona
The study of the stones revealed a new difference between the two sides of the moon, as they are composed of different materials, which indicates a difference in chemical composition. In this regard, Jess says that when they studied the chemical composition of the samples brought by the Apollo missions, they found that many of the samples were rich in potassium, which is rare on Earth, phosphorus, and some radioactive elements.
Because these samples all came from the side near the Earth, the researchers based their comparison on studying random samples of meteorites, to detect this additional difference.
Studying the gravitational field...a mystery that opens doors of questions
The mystery surrounding the far side of the Moon has prompted new missions to study its gravitational field, and scientist Mark Witchuk of the Côte d'Azur Observatory heads NASA's Grail mission to produce the most accurate map. Possible for the Moon's gravitational field, after previous missions failed to obtain satisfactory answers.
Astronomer Mark Wichok from the Côte d'Azur Observatory
The Moon's gravitational field indicates how mass is distributed beneath its surface, and thus we can know what lies beneath the Moon's surface, and how thick its crust is as well. Scientists had realized at that time that the answer to the most prominent questions surrounding the moon lay in studying its gravitational field in the first place.
The “Eb” and “Flo” probes fly around the moon
Both the “Eb” and “Flo” probes flew around the moon, and by studying the subtle differences in the distance separating them, scientists were able to calculate the changes in the moon’s gravity. The results caused an earthquake in the scientific community, as it was found that the average thickness of the crust is approximately 30 kilometers on the near side of the moon, while the thickness reaches 50 kilometers on the far side.
The creation of the moon... digging into ancient history to reveal secrets
What followed the discovery of these differences on the two sides of the Moon prompted scientists to trace the history of its origin and develop appropriate hypotheses to solve all the dilemmas. An important event was held in the early eighties, and planetary scientists agreed to hold a meeting to talk about the origin of the Moon. That conference was described as one of the most prominent conferences. In the history of planetary science.
The giant impact hypothesis is accepted by a large segment of scientists
Although the solar system has many moons, what distinguishes the Earth's moon is that its diameter is relatively large, as it constitutes a quarter of the Earth's diameter, and this is an indication that its formation occurred in an unusual way. The most prominent explanation - which received great consensus - was that the moon was formed due to the accumulation of dust and debris resulting from the collision of a giant body with the Earth.
But this hypothesis lacked an explanation for why the radioactive elements discovered in the Apollo missions’ samples were more present on the side near the Earth. It does not explain the reason for the difference in thickness, nor does it explain the extent of contrast and difference in terrain on both sides.
The difference in crustal thickness between the near and far faces of the Moon raises intense scientific controversy
After a while, 3 basic theories emerged, competing with each other today, to solve these dilemmas and explain the reason for the existence of these differences. They all started from the hypothesis of a giant collision, but they differed about what happened after that and made the moon have two different faces.
Heat theory... when the Earth was playing the role of the sun
The documentary features a special interview with researcher Mark Witt Schork, who is the author of the first theory that deals with the first moments immediately following the great collision. He says that when the moon was formed, large amounts of energy were released, and the temperature in the moon was very high at that time, and it is likely that it was In a state of complete melting.
Then he added that if the far side of the Moon crystallizes at a faster rate than the near side for some reason, its crust will accumulate more quickly, and thus the thickness of the crust will also be greater. At that time, the Earth was a source of heat, as it played the role of the sun, working to heat the side near the moon.
Did the Moon really form from the debris of a large asteroid colliding with the Earth?
Note that the average distance between the Moon and Earth is 384 thousand kilometers, and no matter how high the Earth’s temperature is, it is impossible for it to heat the surface of the Moon in this way. But what space observatories - which constantly measure the distance between the Earth and the Moon - indicate is that the Moon is moving away from the Earth at a rate of 3.78 cm per year. The distance may seem small, but it is sufficient evidence that the Moon and Earth system was different in the past.
The Russian spacecraft “Luna-3” took the first picture in history of the far face of the Moon in 1959
Scientists added some points to this theory, hypothesizing that collisions and seismic activity may have broken down the crust more easily on the near side, and this may have caused increased volcanic activity on the near side, forming the dark lava plains we see today. While those who object to this theory say that the heat emanating from the Earth cannot cause all this effect, no matter how great it is.
Another severe collision... the secret of the heights on the far side
After reviewing the first theory, the documentary flies to the other side of the planet, and a Chinese specialist takes a different approach to solving this mystery. Computer scientist Ming Hua began using complex computer simulations five years ago to answer these questions.
Computer scientist Ming Hua from Macau University of Science and Technology
Mathematical analyzes have shown that in the distant past, another collision may have occurred on the surface of the Moon, and the scientist “Ming” believes that if the near side of the Moon had been subjected to a collision, it is likely that large quantities of debris would have moved and collected on the far side.
This theory explains the secret of the presence of highlands on the far side, in contrast to what is on the near side, which has rugged terrain. Also, the energy resulting from this collision led to the melting and destruction of the near side, hence its unique radioactive chemical components.
The largest lunar crater is located at the south pole of the moon, and is believed to be the remains of a planetary collision with it
Those who object to this theory believe that there are no traces of such a collision if it really occurred. In addition, if the collision occurred at an early time when the moon was molten, there is no convincing reason for a difference in the spread of mass in this way.
The collision of the two moons...the theory of the quiet embrace around the Earth
The author of the third theory, planetary scientist Eric Asvaug, believes that his theory provides the best answers to solve the mystery of the far side, and he expresses the nature of his work as following a scientific methodology, which requires searching for flaws and shortcomings in the solutions proposed by scientists regarding the moon, and this is what does not necessarily make it popular. Within a wide range of scholars, as he put it.
He believes that the issue of the far side of the Moon is like an impossible plain, approaching the puzzle from a different angle. Therefore, “Eric” studied the pattern of collisions that occur on a much smaller scale, indicating that one of the results of the giant collision that struck the Earth was that it not only left behind the Moon, but rather formed Another disk was also orbiting the Earth, then he asked his question: What if there were two moons instead of one?
Astronomer Eric Asvaug assumes that the giant collision resulted in two moons, and they were orbiting together around the Earth
“Eric” believes that the giant collision resulted in two moons, and they were orbiting together around the Earth, so the system began to be disturbed, due to the two moons rotating around the Earth in one orbit, so their collision was inevitable.
The unique nature of this collision is the basis of the theory, as Eric points out that the idea of planets colliding is not new, as it has been thought for centuries that some planets collide with each other, forming larger planets, and sometimes they destroy each other and their debris is scattered everywhere, and he sees “Eric” said that the collision that occurred here was slow, because when it occurred, the two bodies were not destroyed, but rather merged together.
Planetary scientist Eric Asvaug from the University of Arizona
He added that most collisions in the solar system occur at high speeds, as the Earth revolves around the sun at a speed of 30 kilometers per second, and the normal collision speed is not less than 20 kilometers per second, but we are talking here about two bodies stuck in orbit around the Earth, and this limits the speed of the collision. As happens between two cars racing on a closed track and they collide with each other, and the collision is slow.
According to his theory, the two moons approached each other at a speed not exceeding 2.5 kilometers per second before they collided, and as a result of this slow collision, debris was scattered from the near side to the far side.
The theory of the two moons is that they approached each other at a speed not exceeding 2.5 kilometers per second before they collided
But those who objected to this theory said that the presence of two moons in this theory represents many defects. Among them is that they suggest a complete identity in composition between the two moons, which does not seem reasonable. Another flaw is the possibility of having two moons in one orbit in the first place.
The composition of the moon...a treasure that stores millions of years of history
All three theories discussed in the documentary have been under discussion for several years, and none of them has yet emerged victorious, and the mystery of the two mysterious sides continues to attract lunar scientists from everywhere, because studying the history and origins of the moon provides valuable information about something much bigger than that.
An image showing the thickness of the moon's crust. Blue indicates a slight thickness, while red indicates a thickness of up to 60 kilometers.
Scientist Jess says that planetary scientists and geologists see themselves as investigators, and they try to collect evidence around them to form the history of the solar system. The far side of the moon is a mystery searching for a solution, and therefore scientists look at the moon as a crime scene, and the final result is in front of everyone, but scientists do not They still don't know why, so scientists analyze the stones like investigators analyze DNA or fingerprints.
The moon lacks tectonic plates that are responsible for changing its features
What distinguishes the moon from the Earth is that it does not have tectonic plates, which are primarily responsible for destroying the stones and ancient structure that arose with the formation of the Earth. As for the Moon, it still maintains its ancient basic composition on its surface, and that is a great treasure in the hands of scientists, similar to a time capsule that will lead everyone to... Millions of years from the past.
Settlement and colonization of the moon are future plans to which scientists are paying great attention
The documentary focuses on the upcoming space projects to send humans to the moon again, which will represent a starting point towards the future to solve a mystery whose deadline is at hand, especially since the upcoming “Artemis” flight is in the final stages of its preparations to dock on the moon’s surface and bring samples from the far side, for the answer. On one of the great mysteries of science.