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The moon of the Earth; Features, discoveries, interesting facts and everything you need to know

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The Moon
The moon is the only natural moon of the Earth, which has been the target of research more than any other celestial body.

The moon of the Earth; Features, discoveries, interesting facts and everything you need to know

The moon is Earth’s constant companion and the only moon you can easily see in the night sky. The phases of the moon have always been a guide for mankind for thousands of years; For example, calendar months are roughly equal to the time elapsed from one full moon to the next. Although the moon is close to Earth, it has many secrets hidden in it. For example, it always shows us one side, and at the same time, its apparent size in the sky depends on its position relative to the Earth and the sun.

The Latin word for moon is Luna, from which the English word lunar is derived. Also, in the Greek language, Selene is the name of the mythological god of the moon, from which the word selenology is derived.

Table of Contents
  • How was the moon formed?
  • The distance of the moon from the earth
  • What is the moon made of?
  • Surface characteristics of the moon
  • Moon’s atmosphere and weather
  • The orbit and phases of the moon
  • lunar eclipse
  • The seasons of the month
  • Photos and images of the moon
  • Earth rising from the moon
  • A close-up view of the impact crater
  • Full supermoon
  • Apollo 10 souvenir
  • The mountains of the moon
  • A station on the way to Jupiter
  • Image of Artemis
  • Discoveries and observations of the moon
  • space competition
  • Current missions
  • The future of lunar exploration
  • Interesting facts and tips about the moon
  • There are other theories about the formation of the moon
  • The moon’s atmosphere has a mysterious composition
  • The moon has a magnetic field
  • The moon once had a thicker atmosphere
  • Jules Verne wrote one of the most famous stories about traveling to the moon
  • Neil Armstrong was the first man to land on the surface of the moon
  • NASA plans to build a base on the moon
  • Conclusion

How was the moon formed?

According to a leading theory, the Earth’s moon was formed about 4.5 billion years ago and about 95 million years after the birth of the solar system (the age of the solar system is 4.6 billion). At that time, many space rocks were moving in the vicinity of our planet. According to astronomers, it was at this time that the early Earth collided with a body the size of Mars called Tia. This collision caused parts of our world to melt and leave the earth’s atmosphere. The materials removed from the earth formed the moon.

Some astronomers have proposed changes to the above theory. For example, the early Earth turned into donut-shaped molten rock after the collision with Theia. As this space donut cooled, the material on its outer edge turned into small moons and eventually formed the moon itself.

Half moonThe moon was formed approximately 4.5 billion years ago.

The distance of the moon from the earth

The average distance of the moon from the Earth is approximately 384,400 km. However, this distance is not constant because the Moon orbits the Earth in an elliptical orbit. At the closest distance of the moon from the earth, this distance decreases to 363 thousand kilometers. When the moon is at its furthest point from the earth, this distance reaches 405 thousand kilometers.

What is the moon made of?

The moon probably has a very small core that makes up only 1-2% of its mass and its diameter reaches 680 km. Most of this core is probably composed of iron, but a lot of sulfur and other elements are also found in it.

The diameter of the rocky mantle of the moon is approximately 1330 km and it is composed of iron and magnesium rocks. Magma in the mantle made its way to the moon’s surface in the past and was released through volcanic eruptions over a billion years. This eruption occurred between four billion and three billion years ago.

The thickness of the moon’s crust, which forms the lunar surface, reaches 70 km. The outermost part of the shell is broken and disorganized due to the large number of collisions.

In general, the moon, like the four inner planets of the solar system, is a rocky body and is covered with a large number of impact craters that were formed by the impact of asteroids millions of years ago.

The average composition of the lunar surface by weight is as follows: 43% oxygen, 20% silicon, 19% magnesium, 10% iron, 3% calcium, 3% aluminum, 0.42% chromium, 0.18% titanium and 0. 12 percent of manganese.

Orbiters have also discovered traces of surface water on the moon’s surface, possibly originating from beneath the surface. Continuous observations by the Lunar Reconnaissance Orbiter (LRO) show that water is more abundant on the south-facing slopes of the moon, and according to a 2017 study, the interior of the moon could also be full of water.

Surface characteristics of the moon

Ancient lava flows on the surface of the moonAncient lava flows on the surface of the moon

You can clearly see large dark areas on the surface of the moon. These areas are called “Maria” or “Maria” which is the Latin word for sea. The reason for choosing this name is that in the past people considered these areas to be seas of the moon. Today we know that these areas are actually scratches on the moon’s crust that were formed by lava flows billions of years ago.

Due to the absence of weather, almost no erosion occurs on the surface of the moon

Impact craters are other surface features of the moon. These craters are the result of meteorite and asteroid bombardment about a few billion years ago. Since the Moon has almost no atmosphere or active plate tectonics, no erosion has occurred to erase these craters, and as a result, these craters have remained unchanged since their formation.

On the other side of the moon, there is the Aitken Antarctic Basin, which is a crater with a diameter of 2,500 km and a depth of 13 km. The blue regions of the moon are located in the dark polar regions, which can be used for future exploration.

Moon’s atmosphere and weather

A very thin atmosphere covers the moon, with a density of only 100 molecules per cubic centimeter. In contrast, the Earth’s atmosphere has a billion billion times more molecules per cubic centimeter at sea level. The total mass of lunar gases reaches 25,000 kilograms, which is almost the same as a full cargo truck.

Water moleculesAs the temperature increases, water molecules are separated from the surface and as the temperature decreases, they disperse in colder regions and the moon’s atmosphere.

Moon’s atmosphere, which is also called the exosphere, is a combination of argon 40, helium 4, oxygen, methane, nitrogen, carbon monoxide, carbon dioxide, sodium, potassium, radon, polonium, and even small amounts of water. Some of these elements are left over from the cooling of the moon. Others were brought to the moon by comets.

Moondust is a combination of small and sharp particles of volcanic glass that shatter the lunar soil due to the impact of small meteors. The very thin atmosphere of the moon makes these particles rarely erode; For this reason, moon dust can damage astronauts’ equipment and clothes. This dust is extremely harmful to human health.

The orbit and phases of the moon

The influence of the moon’s gravity on the earth causes the rise and fall of the sea level or the phenomenon of tides. These tides occur on a smaller scale in lakes, the atmosphere, and even the Earth’s crust itself. The pull of the moon also slows down the speed of the earth’s rotation, which is called tidal braking; An event that increases the length of the day by 2.3 milliseconds per century. The energy that the Earth loses is absorbed by the Moon and increases its distance from the Earth. The moon moves 3.8 cm away from the Earth every year.

The moon appears in eight phases in its orbit around the Earth. One of the important points about the lunar phases is that the sun always illuminates exactly half of the moon. Lunar phases are created by changing the angle (relative positions) of the Earth, Moon, and Sun compared to each other. In simpler terms, the phase cycle of the moon can be described as follows: new moon and full moon and the phases in between.

The new moon appears when the moon is between the earth and the sun and these three bodies are in relative alignment with each other. In this case, the bright part of the moon is exactly on the other side of the moon, which terrestrial observers cannot see due to the ecliptic lock. In the full moon phase, the earth, moon and sun are in relative alignment just like the new moon phase, but this time the bright side of the moon is placed towards the earth, and the dark side is completely hidden from view.

Lunar eclipse

lunar eclipseSometimes the moon appears red during a total lunar eclipse

During a lunar eclipse, the Moon, Earth, and Sun are in a straight or relatively straight line. A lunar eclipse occurs when the Earth is directly between the Sun and the Moon and the Earth’s shadow falls on the face of the Moon. A lunar eclipse occurs only during a full moon. During a total lunar eclipse, the moon may appear red in the night sky because it is in shadow.

The seasons of the month

The axis of rotation of the Earth has a deviation of 23.5 degrees with respect to the plane of the ecliptic, and this issue causes the seasons on the Earth. On the other hand, the axial deviation of the moon is only 1.5 degrees, and for this reason, no significant difference can be seen in the seasons of the month. In this way, some areas of the moon are always exposed to sunlight and some areas are permanently in darkness.

Photos and images of the moon

Due to the close distance between the moon and the earth, many spacecraft and ground and space telescopes have photographed it. In this section, we introduce some of the most attractive images of the moon from different angles.

Earth rising from the moon

Earth rising from the moonA view of Earth rising from the moon captured by South Korea’s Danori spacecraft

The sunrise is one of the most beautiful events that can be seen from the surface of the moon. This image shows Earth’s view of the Moon as our planet rises above the lunar surface, captured by South Korea’s Danori spacecraft in November 2022.

A close-up view of the impact crater

Moon impact craterTico impact crater

You can see a close-up of Tico’s impact crater in the image above. This massive impact crater is located on the southern side of the moon and was captured by the Greenbank Telescope in West Virginia. This photo is the most detailed image ever taken by a ground-based telescope of the lunar impact crater.

Full supermoon

Full supermoonA view of the full supermoon in front of the New York World Trade Center antenna

A full supermoon is a popular subject for many amateur and professional astrophotographers. This image shows the full supermoon in front of the World Trade Center antenna in New York City.

Apollo 10 souvenir

The moon from the perspective of Apollo 10The moon from the perspective of Apollo 10

The above image was captured by the Apollo 10 spacecraft in 1969. This spacecraft was NASA’s second manned spacecraft to orbit the moon and was a preparatory mission for the Apollo 11 landing, during which, for the first time in human history, astronauts landed on the surface of the moon.

The mountains of the moon

The mountains of the moonThe mountains of the moon

In this image, you can see the mountains of the moon from the perspective of NASA’s Lunar Exploration Orbiter in 2009. Moon mountains are formed by asteroid impacts.

A station on the way to Jupiter

Galileo spacecraft photo of the moonGalileo probe image of the moon

This beautiful image was captured by NASA’s Galileo spacecraft on its way to Jupiter in the mid-1990s. Galileo’s main mission was to study the planet Jupiter and its moons.

Image of Artemis

The moon as seen by the Orion spacecraftThe sunrise of the earth and the moon from the perspective of Orain spacecraft

The image above shows the Earth rising from behind the Moon as captured by the Orion spacecraft on NASA’s Artemis 1 mission in 2022.

Discoveries and observations of the moon

Some ancient societies believed that the moon is a ball of fire, while others thought it was a mirror that reflected the land and seas of the earth, but according to the ancient Greek philosophers, the moon was actually a sphere that revolved around the earth and the light of the sun. reflected

The ancient Greeks also believed that the dark areas of the moon were seas and the light areas were land. It was from this time that the names “Maria” and “Ter”, the Latin words for sea and land, were chosen for these areas. Galileo Galilei, the famous Renaissance astronomer, first observed the moon using a telescope in 1609. He described surface mountains that were completely different from popular belief.

Space competition

In 1959, the Soviet Union landed the first spacecraft, Luna 2, on the surface of the moon, and in the same year, the Luna 3 spacecraft captured the first images of the far side of the moon. These missions marked the beginning of the unmanned missions of the Cold War and the Soviet-US space race to reach the moon.

The missions of many early probes were either failures or partial successes. However, over time, these missions brought back valuable information about the moon’s surface and its history. The United States launched a series of missions called Pioneer, Ranger, and Surveyor, while the Soviet Union sent probes called Luna and Zond to the moon.

Apollo 12 lunar moduleApollo 12 lunar module

The United States sent astronauts into orbit and the surface of the moon in the 1960s and 1970s. Apollo 8 was the first manned mission to orbit the moon in 1968.

In 1969, astronauts landed on the surface of the moon during the Apollo 11 mission. Since then, five more surface missions have been successfully completed. Apollo 13 failed to land on the surface and returned home safely. Since then, the moon has remained the only space body on which humans have managed to land.

In total, the Apollo missions returned 382 kilograms of rock and soil to Earth for examination. Scientists continue to study rocks and make new discoveries as technology advances. For example, in 2013, water was discovered in Apollo 15, 16, and 17 samples.

The Soviet Union was still active in the field of robotics in the 1960s and 1970s. The first robotic sampling mission was launched with Luna 16 in September 1970 after several failed attempts. The Russians built the first robotic lunar rover named Lunakhod 1 just two months later. Lunakhod 2 was unveiled in 1973. The last successful Soviet mission to the moon was carried out in 1976 with Luna 24, and after that, the only moon of the earth was forgotten in the field of space exploration for several years.

Current missions

After the Apollo program ended more than a decade later, lunar exploration resumed in the 1990s. Since then, the space organizations of other countries such as Japan, the European Space Agency, China, and India have also joined the moon space race. China and India have succeeded so far among the new countries in the field of conquering the moon.

The future of lunar exploration

Other countries such as Japan, Russia, and the United Arab Emirates are currently planning and implementing a mission to the moon. In 2019, US President Donald Trump announced that NASA was working to send humans back to the moon by early 2025. Of course, this deadline is no longer achievable and the return of man to the moon will probably not be possible before 2028.

The Return to the Moon program, now called Artemis, is a project involving international and commercial partners that strives to carry out manned missions and permanently establish humans on the Moon, using NASA’s new space launch system, the Space Launch System (SLS), and the Starship rocket. SpaceX uses

The first Artemis mission, Artemis 1, completed an unmanned lunar orbit mission and returned to Earth in November 2022, setting the stage for subsequent manned missions. NASA’s Artemis 2 mission will send the first humans into lunar orbit in half a century, and then Artemis 3 will land the first female astronaut as well as the first person of color on the lunar surface.

Interesting facts and tips about the moon

The moon is one of the most attractive objects in the night sky for earthlings. Due to the proximity of this moon to the Earth, we can learn a lot of data about its formation and also about the planet Earth. Despite all the discoveries and research, the moon has many secrets. In this section, we introduce some examples of the most interesting facts about the month.

There are other theories about the formation of the moon

Apart from the theory of Tia’s collision with the Earth and the formation of the Moon, another theory claims that the Earth rotated so fast in its early life that its molten rocks flew into space and eventually formed the Moon. However, there is no evidence of rapid Earth rotation to support this idea. According to another theory, the moon is actually a dwarf planet similar to Pluto that is trapped in the Earth’s orbit. Scientists also reject this theory.

The moon’s atmosphere has a mysterious composition

Today we know that the moon’s atmosphere is a mixture of argon, helium, neon, sodium, polonium, potassium, and radon. However, some scientists raise the question of why, like the atmosphere of other objects, traces of oxygen and nitrogen are not seen in the moon’s atmosphere. On the other hand, the crust of the moon has both elements besides magnesium, hydrogen, and carbon. So far, scientists have not been able to find an answer to the mystery of the lack of nitrogen and oxygen in the moon’s atmosphere.

The moon has a magnetic field

One of the lesser-known facts about the moon is its magnetic field. Of course, this magnetic field is very weak compared to the Earth. Evidence from manned missions to the moon shows that the ancient moon had a magnetic field equal to that of Earth. Because of these findings, scientists believe that this magnetic field has weakened as the core of the moon has cooled and solidified.

Aldrin on the moon againA photo of Buzz Aldrin on the moon taken by Neil Armstrong

The moon once had a thicker atmosphere

According to a NASA discovery in 2017, the moon’s atmosphere was thicker in the past. The early moon’s atmosphere had sufficient elements despite continuous volcanic activity and a strong magnetic field. Over time, with the disappearance of volcanic activity and the weakening of the magnetic field, the solar winds destroyed the moon’s atmosphere.

Jules Verne wrote one of the most famous stories about traveling to the moon

Jules Verne, a French novelist, wrote the novel From the Earth to the Moon in 1865. The story of this novel focuses on the construction of a cylinder that can send an insulated object to the moon. Passengers are also inside this object. Finally, this cylinder is successfully built and launched. Verne describes the actual journey to the moon and the return of the passengers to Earth in the sequel to this novel, In Lunar Orbit.

Neil Armstrong was the first man to land on the surface of the moon

The Apollo 11 mission, launched on July 16, 1969, made history by landing on the lunar surface on July 20. Neil Armstrong, holding the American flag, set the record of being the first man to land on the surface of the moon. At the moment of stepping on the moon, he said this historical sentence:

A small step for a man and a giant leap for humanity

About 500 million people watched this historic moment from the ground.

NASA plans to build a base on the moon

From the beginning of this century, NASA began its plans to return to the moon by the end of the 2020s. The goal of the US space agency’s latest effort is to build the first permanent habitat on the moon by 2028. The success of this plan could have many implications for life on the Moon and other planets.

Conclusion

The moon has been the only moon of the Earth and one of the most attractive destinations for human exploration. The moon is full of impact craters that have remained unchanged for years due to the lack of weather. Also, this moon shows us only one side due to the tidal lock with respect to the Earth. Also, the gravity of the moon causes the creation of gravitational forces and so-called tides in the oceans and seas of the Earth.

Ancient people thought that the dark areas of the moon were seas and the light areas were land. However, later Galileo showed with more observations that these regions are only surface features and mountains of the moon. Competition to reach the moon intensified in the 20th century with Soviet and US missions, and finally, in 1969, the US landed the first man on the surface of the moon.

In the 21st century, mankind dreams of permanent and long-term residence on the surface of the moon. One such effort is NASA’s Artemis program, which aims to return the first humans to the moon in half a century and pave the way for permanent lunar bases.

Space

Maybe the Earth is not doomed by the death of the sun

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A global discovery of an Earth-sized rock orbiting a white dwarf suggests a future where our planet could survive beyond the Sun.

Maybe the Earth is not doomed by the death of the sun

Will the sun one day destroy the earth? This may or may not happen. Astronomers have spotted a rocky planet the size of Earth orbiting a white dwarf, hinting at a future in which our planet outlives its star.

In 6 billion years, the sun will grow and become a red giant star. At this point, Mercury and perhaps Venus will be swallowed up, and for a long time, we thought that planet Earth would also be incinerated. But maybe the blue planet is not doomed, even though it may become an uninhabitable world in the next 6 billion years.

According to the New York Times, scientists have discovered a rocky planet orbiting a star that has passed its red giant phase. The planet now orbits a white dwarf, a smaller stellar body left over after a star burns out.

Importantly, the planet appears to have once been in the same position as the Earth now orbits our Sun. Before being swallowed up by its dying star, the rocky planet was pushed into a distant orbit, twice the distance between Earth and the Sun. In this way, the discovered world is considered the first rocky planet that has been seen rotating around a white dwarf.

A rocky Earth-like planet has survived the destruction of its star

“We don’t know if Earth can survive,” said astrophysicist Kaming Zhang of the University of California, San Diego, who led the study published in the journal Nature Astronomy. “If it survives, it will become such a system.”

The rocky planet is about 4,000 light-years away and in 2020, the South Korean Radio Astronomy Observatory discovered it using a process called gravitational microconvergence. The Korean team observed the star of the rocky planet while passing in front of a distant star, and that star magnified the amount of light reaching the telescope by a thousand times. This effect, known as convergence or gravitational lensing, makes it possible to identify very distant and faint objects.

That particular event was a one-off event, and the chances of further detailed observations are limited until powerful new telescopes can get a better look at the rocky planet in the future. But Dr. Zhang and his team were able to do more last year at the Keck Observatory in Hawaii and found out that the planet’s star is actually a white dwarf.

The researchers calculated that at least two objects are orbiting the white dwarf. One of them was a brown dwarf; That is, the failed star that had never ignited by nuclear fusion and was located at a great distance from the central star. But the other object is a planet with a mass of about 1.9 times that of Earth, which orbits closer to the star’s period and is therefore likely to be a rocky world.

By modeling the evolution of the star system, Zhang’s team calculated that the planet may have once been in a habitable orbit like Earth. The star was probably the same size as ours. “We expect the star to have been roughly the same mass as the Sun,” Dr. Zhang said.

A microlensing event revealing a white dwarfGravitational convergence shows the white dwarf shown by the vertical white lines. The researchers captured images of the star years before the event (a), shortly after the background star peaked in 2020 (b), and after it disappeared in 2023 (c).
Keck Observatory

But as the star ran out of fuel, it lost some of its mass, causing the rocky planet’s orbit to lengthen. The rocky planet escaped from the expanding red giant phase of the star and survived to the white dwarf stage.

A handful of gas planets have been found orbiting white dwarfs, but they were either in more distant orbits or had migrated inward and closer after the red giant phase. “If Dr. Zhang’s diagnosis is correct, this would be the first rocky planet orbiting such a star,” said Susan Mulally, an astronomer at the Space Telescope Science Institute in Maryland. “It’s definitely the smallest and clearest rocky planet we’ve ever found around a white dwarf.”

A handful of gas planets have been discovered orbiting white dwarfs

Stephen Kane, an astronomer at the University of California Riverside, noted that he was excited when he first read the paper. He has previously investigated whether planets can survive when their stars pass through the red giant phase, so he is intrigued by the new discovery. However, the presence of the brown dwarf complicates everything. If the brown dwarf was once closer to the star but moved outward, it could change the dynamics of the entire system, he explained. That means, maybe there are other planets that have been thrown out and the planets that are currently observed are among the survivors.

NASA is scheduled to launch the Nancy Grace Roman Space Telescope before 2027 and is expected to find more planets through gravitational microconvergence. Perhaps some of them are orbiting white dwarfs.

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Alien life may be hiding under the Martian ice cover

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Alien life may be hiding under the Martian ice cover. Martian dust ices in mid-latitudes are exposed to sunlight and provide a favorable environment for the search for possible Martian life.

Alien life may be hiding under the Martian ice cover

A new study suggests that the conditions necessary for photosynthesis on Mars may exist beneath the dusty ice cover in the Red Planet’s mid-latitudes.

Photosynthesis is a process by which living organisms such as plants, algae, and cyanobacteria can produce chemical energy. This process requires water and light to progress and produces much of the oxygen in the Earth’s atmosphere. According to the new findings, Martian ice layers of sufficient thickness can filter out intense solar radiation while still allowing sunlight to penetrate beneath them for photosynthesis, creating so-called “radiatively habitable” zones.

Since the process of photosynthesis is suitable for light, the new results should be considered in sufficient light conditions. While the findings don’t prove that life exists on Mars, or even existed in the distant past, they can give scientists ideas to search for. Aditya Kholler, a postdoctoral researcher and research supervisor at NASA’s Jet Propulsion Laboratory, says the Martian dusty ice in the mid-latitudes is exposed to sunlight and could be an accessible environment to search for life on Mars today.

NASA's Discovery OrbiterImages of the Red Planet from NASA’s Mars Exploration Orbiter (MRO).

Earth vs. Mars

Both Earth and Mars are located in a range known as the Sun’s life belt; A region around a star where the temperature is favorable for the flow of surface liquid water. Although 71% of Earth’s surface is covered by liquid water oceans, Mars has a mostly dry landscape.

Discoveries of Mars rovers such as Curiosity and Perseverance have shown that conditions on Mars are different. Surface features such as dry lake beds and river forks discovered by these robots indicate the presence of surface liquid water billions of years ago. Additionally, Mars missions such as the Mars Reconnaissance Orbiter (MRO) have often discovered water ice in unexpected areas.

According to scientists, Mars lost its liquid water billions of years ago; Just as the planet’s magnetic field weakened (Earth’s magnetism is still very strong) and much of its atmosphere was lost. Thus, there were few barriers to surface water evaporation. The absence of a thick atmosphere also means that today’s Mars is under the bombardment of harmful ultraviolet radiation from the sun, which is fatal for living organisms and can destroy the complex molecules needed for life.

Waterholes in Terra Sirnum areaNASA’s Discovery Orbiter image of craters in the Cyrene region of Mars.

Unlike Earth, Mars does not have an ozone protective shield; As a result, the level of surface ultraviolet radiation is 30% higher than that of the earth; Therefore, photosynthesis on Mars probably occurs in places that are inside the dusty ice; Because the dusty ice cover can block harmful UV rays on the surface of Mars, and liquid water is highly unstable due to the planet’s dry atmosphere.

Using computer simulations, the researchers found that Martian dusty ice may melt from the inside and that the overlying ice cover prevents shallow subsurface liquid water from evaporating in the dry Martian air. According to Kholer:

Thus, two key elements for photosynthesis could be present in mid-latitude Martian dust ices. Photosynthesis requires sufficient amounts of sunlight as well as liquid water. Two previous independent simulations of dense Martian snow show that if small amounts of dust (less than one percent) are present in the snow, subsurface melting could occur in the mid-latitudes of present-day Mars.

“With the discovery of dusty ice that was exposed a few years ago within snow masses in Martian glaciers, there is a mechanism for subsurface melting that could underlie the formation of shallow subsurface liquid water,” Kholer added. According to Kholer, the dusty ice on the ice cap can block UV radiation from the surface of Mars and also allow sunlight to penetrate below the surface for photosynthesis.

Watershed of Dao Wallis areaAn image from NASA’s Discovery Orbiter of a puddle in the Dao Wallis region of Mars.

The depth required for the formation of radiative habitable zones depends on the amount of dust in the ice. Very dusty ice can block a lot of sunlight, the researchers’ simulations show. However, ice with 0.01 to 0.1 percent dust allows for the formation of a radiative zone between 5 and 38 cm deep. Less contaminated ice allows for a deeper and wider radiation zone at a depth between 2.2 and 3.1 meters.

According to researchers, the polar regions that have the most ice on Mars are too cold for habitable radiation zones; Because they do not have the subsurface melting mechanism. Such a mechanism probably occurs in the middle latitudes of the Red Planet.

Scientists have taken scientific support for their theory from evidence on planet Earth. Kholer says:

I was surprised to learn that similar areas for life exist within dusty and sedimentary polar ice. These areas are called cryoconite cavities and are formed when dust and sediment on the ice melts into it because it is darker than the ice.

Dust ice cavities in the earth's glaciersEvidence from Earth: Cryoconite-formed cavities on the Matanuska Glacier, Alaska, 2012

Every summer, due to heating by sunlight, liquid water gathers around the dark dust inside the ice. This happens because the ice is semi-transparent, allowing sunlight to penetrate below its surface. According to Khüler, the researchers discovered that the tiny organisms that live in these shallow subsurface habitats on Earth usually go dormant in the winter, when there isn’t enough light to form liquid water in the dusty ice.

Of course, none of the above findings mean that photosynthetic life exists on Mars or probably ever existed; But it could inspire further research into the possibility of radiation habitats on the Red Planet. Kholer adds:

I am working with a group of scientists on improved simulations of where and when the ice melts on present-day Mars. Additionally, we are recreating these dusty ice scenarios in the lab to investigate them in more detail.

The results of the research were published on October 17 in the journal Communications Earth & Environment.

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Why is it still difficult to land on the moon?

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More than half a century after the first spacecraft to reach the moon, a successful landing on Earth’s only moon remains a challenge for space agencies and private companies.

Why is it still difficult to land on the moon?

This year, the private company Spacel and the Indian Space Organization both met tragic ends when they tried to land their spacecraft on the surface of the moon. Despite the astonishing leaps made in recent decades in computing, artificial intelligence and other technologies, it seems that landing on the moon should be easier now; But recent setbacks show that we still have a long way to go with safe and trouble-free landings on the surface of Earth’s only moon.

50 years after sending the first man to the surface of the moon, the question arises as to why safely landing a spacecraft on Earth’s nearest cosmic neighbor is still a difficult task for space agencies and private space companies. Stay with Zoomit to check the answer to this question.

Why is the lunar landing associated with 15 minutes of fear?

Despite the complexities of any space mission, sending an object from Earth into orbit around the moon today is easy. Christopher Riley, the director of the documentary film In the Shadow of the Moon produced in 2007 and the author of the book Where We Stood (2019), both of which are about the history of the Apollo 11 mission, explained the reasons for the difficulty of landing on the moon in an interview with Digital Trends. is According to him: “Today, the paths between the Earth and the Moon are well known, and it is easy to predict them and fly inside them.”

Chandrayaan-2
Chandrayaan 2 mission launch

However, the real challenge is getting the spacecraft out of orbit and landing it on the lunar surface; Because there is a delay in the communication between the Earth and the Moon, and the people in the control room who are present on the Earth cannot manually control the spacecraft in order to land it safely on the Moon. As a result, the spacecraft must descend automatically, and to do so, it will fire its descent engines to slow its speed from thousands of kilometers per hour to about one meter per second, in order to make a safe landing on the lunar surface.

For this reason, the director of the Indian Space Research Organization (ISRO), who was trying to land the Vikram lander last month, described the final descent of the spacecraft as “frightening 15 minutes”; Because as soon as the spacecraft enters the landing stage, the control of its status is out of the hands of the mission control members. They can only watch the spacecraft land and hope that everything goes according to plan, that hundreds of commands are executed correctly, and that the automatic landing systems gently bring the spacecraft closer to the surface of the moon.

The Great Unknown: The Landing Surface

One of the biggest challenges in the final descent phase is identifying the type of landing site. Despite the availability of instruments such as the Lunar Reconnaissance Orbiter (LRO) that can capture amazing views of the lunar surface, it is still difficult to know what kind of surface the spacecraft will encounter when it lands on the moon.

Beresheet crash site
Left: Breshit crash site. Right: The ratio of the before and after images highlights the occurrence of minor changes in surface brightness.

Leonard David, author of Moon Fever: The New Space Race (2019) and veteran space reporter, says:

The Lunar Reconnaissance Orbiter is a very valuable asset that has performed really well over the years; But when you get a few meters above the surface of the moon, complications appear that cannot be seen even with the very powerful LRO camera.

Even today, despite the imaging data available, “some landing sites still have unknown remains,” Riley says. He notes that the Apollo 11 mission included an advantage that today’s unmanned landers lack, which is the presence of an astronaut’s observer’s eyes that can closely observe the surface of the spacecraft’s landing site. As you probably know, in the mission that led to the landing of the first man on the surface of the moon, the Eagle computer was guiding the spacecraft to a place full of boulders; But to avoid hitting the rocky surface of the moon, Armstrong took control of the spacecraft himself and landed it on a flat surface.

Apollo 11 / Apollo 11

The uneven surface of the landing site had caused many problems in previous lunar missions such as Apollo 15. In this mission, the astronauts were told that as soon as the spacecraft touched the surface of the moon, they should turn off the engines to prevent dust from being sucked in and the risk of a return explosion. But the Apollo 15 spacecraft landed in a crater, and because of this, one of its legs came into contact with the surface earlier than the others. When the crew shut down the engines, the spacecraft, moving at a speed of 1.2 meters per second, experienced a hard landing. The lander landed at an oblique angle, and although it eventually landed safely, it nearly overturned, causing a fatal disaster.

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The difficult landing of Apollo 15 introduced another complicating factor in lunar landings: lunar dust. The Earth’s moon is covered with dust that is thrown into the air by any movement and sticks to everything it comes in contact with. As the spacecraft approaches the surface of the moon, huge plumes of dust are kicked up that limit the field of view and endanger the spacecraft’s electronics and other systems. We still do not have a solution to deal with the dust problem.

An achievement that has been achieved before

Another reason why the moon landing remains a challenge is that gaining public support for lunar projects seems difficult. Referring to Neil Armstrong and Buzz Aldrin, the two astronauts who walked on the moon during the Apollo 11 mission, David says, “We convinced ourselves that we had sent Neil and Buzz [to the surface of the moon]; “As a result, when it comes to lunar missions, people may say we’ve been there before and we’ve had this success.”

Apollo 11 / Apollo 11

But in reality, our understanding of the moon is still very little, especially in relation to long-term missions. Now, with a 50-year gap between the Apollo missions and NASA’s upcoming Artemis project, the knowledge gained has been lost as engineers and specialists retire. David says:

We need to recover our ability to travel into deep space. We haven’t gone beyond near-Earth orbit since Apollo 17 and since 1972. NASA is no longer the same organization that put men on the moon, and there is a whole new generation of mission operators.

The importance of redundancy

As the first private spacecraft entered into orbit around the moon, the Space project was of considerable importance; But its failure to land smoothly on the surface of the moon made the achievement of landing on the surface of the moon still remain in the hands of governments. However, we can expect more private companies, such as Jeff Bezos ‘ Blue Origin, which is developing its lunar lander, to target the moon in the future. According to Elon Musk, even the giant SpaceX Starship spacecraft, which is being built with the ultimate goal of sending a human mission to Mars , can also land on the moon.

According to David, private companies’ participation in lunar landings has advantages such as increased innovation. However, companies are under pressure to save money, and this can lead to a lack of redundancy and support systems that are essential in the event of errors and malfunctions. Lunar rovers typically include two or even three layers of support systems. David is concerned that private companies will be encouraged to eliminate these redundancies in order to cut costs and save money.

Crew Dragon
Crew Dragon SpaceX passenger capsule

“We saw Elon Musk’s Dragon capsule catch fire after a failed test on the stand,” says David, referring to the explosion of the SpaceX spacecraft in April, which had no crew on board. “This accident was kind of a wake-up call about how unpredictable the performance of spacecraft can be.” David compared the Crew Dragon incident to the Apollo 1 disaster, which killed three NASA astronauts during a test launch in 1967.

Another problem related to the lack of redundancy systems is the lack of information needed when an error occurs. As for the recent landings, it seems that the SpaceX crash was caused by human error; however, it is not clear what caused the failure of Chandrayaan 2 in the calm landing, and it is possible that without the necessary systems to record and send information to the lander, we will never find out the main reason for the failure of this mission. Without the required data, it becomes much more difficult to prevent problems from reoccurring in the future.

The future of lunar landings

Currently, many projects are underway to facilitate future moon landings. Ultimately, we need to be able to build the necessary infrastructure for a long-term stay on the moon.

Moonrise Project
Conceptual design of Moonrise technology on the moon. On the left side is the Alina lunar module, and on the right side, the lunar rover equipped with Moonrise technology melts the lunar soil with the help of a laser.

If we can make long-term stays on the moon possible, or even build a permanent base there, landing spacecraft on the lunar surface will be much easier. By constructing the landing sites, a flat, safe, and free surface of unknown debris can be created for the landing of surface occupants. For example, researchers are currently conducting research at NASA’s Kennedy Space Center to investigate the feasibility of using microwaves to melt the lunar soil (regolith) and turn it into a hard foundation so that it can be used as a landing and launch site. The European Space Agency is also investigating how to use 3D printing to create landing sites and other infrastructure on the moon.

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Other ideas include the use of lidar remote sensing systems, which are similar to radar systems; But instead of radio waves, it uses lasers to land the spacecraft. Lidar technology provides more accurate readings and uses a network of GPS satellites to help guide the spacecraft during landing.

The problem of public support

As important as technology is, public interest and support are essential to the success of the lunar landing program. “Apollo had enormous resources that are perhaps only comparable today to China’s space program,” says Riley. “Remember that Apollo carried the best computer imaginable, the human brain.” It goes without saying that there is an element of luck involved in every landing.

Mike Pence
US Vice President Mike Pence speaking at the 50th anniversary of the Apollo 11 mission

Finally, there is the question of what kind of failure is acceptable for people. David says:

I think we have to be serious about the fact that we’re probably going to lose people. There is a serious possibility that the manned lunar lander will crash and kill the astronauts inside. The American people continued to support NASA despite the failures and bad luck of the Apollo program, But at that time there was a lot of pressure to compete with the Soviet Union. Without the bipolar atmosphere of the Cold War and the space race, would people still support missions with human lives in between?

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