The abundance of iron oxide in the crust of Mars is the main reason for the red color of the soil. The days and seasons of Mars are similar to Earth’s to a great extent, due to the similarity of the rotation period around the Sun and its axial rotation to Earth. The largest volcanic mountain and the second highest mountain in the entire solar system is located on Mars, and Marineris Valley is one of the largest valleys in the solar system. Mars has two moons named Phobos and Deimos, which have an irregular shape, unlike Earth’s moon. Probably, these two moons were asteroids that were trapped by the gravity of Mars.

Mars is a cold planet and a desert world with a very thin atmosphere. Martian dust storms are so intense that they can cover the entire surface of the planet. The temperature of this planet is so low that the carbon dioxide in the atmosphere directly falls on its surface in the form of snow and ice.

The volume of water ice deep in the Antarctic ice cap of Mars is enough to cover the entire surface of the planet up to a depth of 11 meters. In November 2016, NASA reported findings of subsurface ice on the Utopia Panitia plate. According to estimates, the volume of water discovered is equal to the volume of water in Lake Superior of North America. Mars can be easily seen from Earth with the naked eye as a red dot.

This color image of Mars was captured by the OSIRIS instrument of the European Space Agency’s Rosetta spacecraft in February 2006.

The bright copper color of Mars is due to the abundance of iron-rich minerals in its regolith. Regolith is loose rocks and dust that cover the surface. Earth’s soil is also a type of regolith, with the difference that it is rich in organic matter. According to NASA, iron minerals undergo oxidation or rusting, giving Mars its reddish appearance.

Approximately 4.6 billion years ago, in the early days of the solar system, a disk of gas and dust formed in the orbit of the young sun. Two theories show how, over millions of years, the rocky inner planets of the solar system formed from within this disk of matter. According to an older theory, the dust in the inner solar system formed into larger masses, and these masses gradually became the size of the Earth’s moon. The collision of these planetary embryos eventually led to the formation of planets such as Mercury, Venus, Earth, and Mars.

Artist’s conceptual image of the solar nebula, a cloud of gas and dust in which the planets of the solar system formed.

However, a newer theory considers a different growth process. In this process, millimeter-sized pebbles moved towards the sun from the outer part of the solar system. Along the way, these pebbles took the form of inner planetary embryos and gradually reached their current size. Both theories are based on theoretical models and computer simulations that aim to recreate the conditions and variables of the early solar system. Both theories also describe possible pathways of planet formation; But which theory is correct? Which process actually occurred?

Unlike Earth, which is tectonically active and rocks change over billions of years, Mars has no tectonic activity; Therefore, the oldest Martian rocks are present on its surface. Studying these rocks is a way to find out how the red planet was formed. Also, scientists can answer these questions by examining extrasolar planets and their similarity to the planets of the solar system, as well as the same elements in the formation of Earth and Mars; But none of the theories have been conclusively proven yet.

The size of a planet depends on the amount of matter and the initial cloud of gas and dust. According to NASA, the radius of Mars is nearly 3390 km; But Mars is not perfectly circular like Earth. Rather, due to the rotation, it has a slight bulge in the equatorial part. One of the main reasons why Mars is small compared to Earth is the difference in gravity between the two. The gravity of Mars is about one-third that of Earth because it has less mass to attract objects to its surface. This feature can be useful for research and discoveries to some extent. For example, the Ingenuity helicopter flies more easily and takes off from the surface of Mars due to lower gravity; But this gravity has its problems and makes the atmosphere of this planet very thin.

Comparison of Earth and Mars

The diameter of Mars is half the diameter of the Earth and its surface area is slightly less than the land area of ​​the Earth. Mars is less dense than Earth. Its volume is 15% of the Earth’s volume and its mass is approximately 11% of the Earth’s mass; As a result, the gravity of Mars is 38% of the gravity of Earth. Therefore, a person weighing 100 kg on Earth will be 62 kg on Mars, but his mass is the same on Earth and Mars.

The dust that covers the surface of Mars is like talcum powder. Under a layer of dust, the Martian crust is placed, most of which is made up of basalt volcanic rocks. Mars soil contains nutrients such as sodium, potassium, chloride, and magnesium. The Martian crust is thought to be one piece. Unlike Earth, the Red Planet has no tectonic plates. Tectonics or plate tectonics float on the mantle and are the main cause of the deformation of the Earth. But since there is almost no movement in the crust of Mars, the molten rocks have gathered in one place and created huge volcanoes on the surface of this planet.

Of course, this does not mean that the shell is immobile. According to researches, probably strong thrusts have led to the creation of Martian slopes. According to the researchers, ice is an important material for smoothing drifts on Mars, even in tropical areas such as Valais Marineris. Any possible life on Mars is probably going on underground. Although astronomers continue to search for signs of past and present life on Mars, no evidence of Martian life has been found so far.

According to the evidence, there has been no volcanic activity on Mars for millions of years. The mantle of Mars is very silent and calm. The mantle is composed of silicon, oxygen, iron, and magnesium, and its thickness reaches 1240 to 1880 km, according to NASA. The center of Mars has a solid core of iron, nickel, and sulfur that does not move; Therefore, this planet does not have a global magnetic field; Without the presence of a magnetic field, cosmic rays hit this planet and turn it into an uninhabitable world.

NASA’s InSight rover has been investigating the interior of Mars since 2018. InSight has measured Martian earthquakes. InSight’s data revealed key insights into the planet’s internal structure. For example, according to the new estimates of this mission, the diameter of the core of Mars is between 1780 and 2080 km and the thickness of its shell is between 24 and 72 km. The mantle forms the rest of the structure. This is while the width of the earth’s core reaches 1,220 km and its mantle reaches 2,900 km. Also, the earth has two types of crust. Continental and oceanic crust, whose thickness is equal to 40 km and 8 km, respectively.

Mars hosts the highest mountains and the deepest and longest valley in the entire solar system. The height of Mount Olympus reaches 27 km, which is almost three times the height of Mount Everest. The depth of the Marineris Valley of Mars is seven kilometers and its width reaches 4000 kilometers from east to west, which is almost equal to the width of Australia.

Scientists believe that the Marineris Valley was created by scratching and stretching the crust. The width of independent internal valleys reaches 100 km. The valleys merge in the central part of the Marineris Valley in an area 600 km wide. Large channels rising from the end of some valleys and layered sediments show that the valleys were once full of water. Mars has the largest volcanoes in the entire solar system, Olympus Mons being one of them. The diameter of this huge volcano reaches 600 km and is so wide that it contains the state of New Mexico.

Olympus Mons is the largest known volcano in the solar system. This image was captured by NASA’s Viking 1 orbiter.

The canals, valleys, and water passages of Mars show that in the past liquid water flowed on the surface of this planet. Some channels are 100 km wide and 2000 km long. Liquid water may be found in cracks and holes in the subsurface rocks of Mars. According to a 2018 study, the salty water beneath the surface of Mars could contain significant amounts of oxygen, which is necessary for microbial life. However, the amount of oxygen depends on both temperature and pressure; The change in the deviation of the rotation axis of Mars causes changes and temperature fluctuations.

A large part of Mars consists of low and flat plates. The northern lands of Mars are among the flattest and smoothest plates in the entire solar system, which were probably formed due to the flow of water on the surface. The surface height in the northern hemisphere of Mars is lower than in the southern hemisphere, and this means that the northern crust is thinner than the southern crust. The difference between north and south could be due to a very large collision that occurred soon after the birth of Mars.

The number of craters on Mars varies in different places and based on the age of the surface. A large part of the southern hemisphere of Mars is very old, as a result, there are many craters in this area, the most famous of which is Hellas Planitia with a width of 2300 km. On the other hand, the northern hemisphere of this planet is younger and has fewer craters. Some volcanoes also have a small number of craters, which indicates that they have recently erupted and the resulting lava has covered the old craters. Some craters have strange deposits of pebbles around them that look like dried mudflows, possibly indicating the presence of subsurface water or ice.

Mars has two prominent ice caps; which are in continuous darkness in polar winter and 25-30% of atmospheric carbon dioxide gas is accumulated in this part in the form of dry ice. When the poles are exposed to sunlight, the frozen carbon dioxide turns back into a gas. These seasonal processes transport a large portion of water vapor and dust, creating Earth-like snow and large cirrus clouds. 70% of the polar ice caps are water. Frozen carbon dioxide also sits in the form of a thin layer with a thickness of approximately one meter only in the winter season on the northern cap, while the thickness of dry ice on the southern cap reaches eight meters.

Due to the thin atmosphere of Mars, its surface conditions are not very favorable for water flow. For this reason, the possible sources of water are either underground or placed in the form of ice caps at the poles. According to past modeling, some of the Martian waters are underground. There are many signs of water in the impact craters; Among the canals that have grooves in their walls due to the passage of water and evidence of erosion and coastlines. As a result, craters may be a clue to underground water.

In the bed of these craters, there is evidence of the existence of water flows in the past, which have settled down over time. According to estimates, the depth of the channels corresponds to the oceans of Mars four billion years ago. Thus, the discovery of water became a prelude to the discovery of life on Mars.

In 2021, the FREND instrument from the Tracer Gas Orbiter (TGO) discovered subsurface water on Mars. The instrument discovered a region with an unusual amount of hydrogen in the Valles Marineris canyon system. Considering that the hydrogen element is abundant in water molecules, it seems that forty percent of the material near the surface of this region is water. This area is as rich in water as the Netherlands. This amount of water in this area, which was much more than expected, could be in the form of ice or water in the soil minerals.

In early 2022, the MRO orbiter discovered traces of water that appeared to have flowed on the surface of Mars 2-2.5 billion years ago. According to previous estimates, the surface water of Mars has evaporated about 3 billion years ago. As a result, based on this finding, the surface water of Mars has flowed on the surface of this planet for a billion years longer than the estimates.

Water is the basic requirement of life. The discovery of water, especially underground liquid water, has increased the hope of discovering Martian life; But to understand the potential of Martian life, it is necessary to go back to 3-4 billion years ago. At that time, Mars and Earth had many features in common. The red planet was hot and humid, had a stable atmosphere, and was far from its current cold and unpleasant face. David Parker, European Space Agency’s Head of Robotics and Human Exploration, says:

At the beginning of its life, the raw materials of the planet Mars were similar to the materials that make up the Earth; But over time, everything changed. This process was just like a kind of collapse.

Mars lost its magnetic field over time. The loss of the magnetic field means that the planet will have no protection against harmful radiation. Mars also lost much of its atmosphere. Because the atmosphere is one of the other necessary criteria for the formation of life on the planet and provides the necessary oxygen. Parker says:

Mars still has a thin atmosphere, most of which is carbon dioxide. The reason for the extreme cold of this planet is its very thin atmosphere.

The Perseverance rover took this photo of the surface of Mars in January 2022. Perseverance is searching for signs of ancient life on Mars.

However, the cold and unprotected Mars did not discourage scientists from searching for signs of life on this planet. NASA’s Curiosity rover discovered organic matter on Mars in 2018. This discovery meant that the building blocks of life once existed or still exist on Mars. NASA researchers say:

Conservation of organic resources is a turning point in understanding life on Mars. Regardless of whether Mars has ancient life, its organic matter can be chemical clues to its current processes and conditions. Curiosity also discovered methane, the simplest organic molecule, on Mars. Methane can also be a clue of chemical processes on Mars.

According to the new findings of the Curiosity rover, evidence of ancient life on Mars has disappeared. The Curiosity rover made a surprising discovery by examining the clay sedimentary rocks around Gale Crater. This impact crater was once a lake that was created by an asteroid hitting the Red Planet about 3.6 billion years ago.

Curiasti sampled two ancient mudstones (a type of clay-containing sedimentary rock) from a dry riverbed, dating back to about 3.5 billion years ago, and both 400 meters apart. By examining these two samples, the researchers realized that one of the veins contained only half of the expected clay minerals. The other vein contained larger amounts of iron oxide, which is responsible for the red color of Mars.

According to researchers, seepages are the main culprit of the disappearance of ancient biological works: extremely salty and salty waters penetrating into clay layers rich in minerals make them unstable and lead to the disappearance of geological and biological works. In general, despite the many similarities between Earth and Mars, the Red Planet is not suitable for life for one simple reason. The diameter of Mars is exactly 53% of the diameter of the Earth (a little more than half); For this reason, Mars is not a suitable environment for maintaining volatile substances suitable for life, including water.

Climate changes on Mars are extreme. The atmosphere of this planet was suitable for the flow of liquid water on the surface in the past, But today only a thin layer of it remains. The climate of Mars depends on several features such as ice caps, water vapor, and dust storms. Sometimes massive sandstorms can cover the entire planet like a blanket for months, turning its skies dusty and red. The atmosphere of Mars is 100 times thinner than the Earth’s atmosphere and 95% of it consists of carbon dioxide. According to NASA data, the atmospheric composition of Mars is :

• Carbon dioxide: 95.32%
• Nitrogen: 2.7 percent
• Argon: 1.6 percent
• Oxygen: 0.13%
• Carbon monoxide: 0.08%
• A small amount of water, nitrogen oxide, neon, hydrogen, deuterium, oxygen, krypton, and xenon.

Orbital images show fluvial sheets and possible vast ocean boundaries in Mars’ past. Although the Mars rovers have managed to discover evidence of limestone on the surface of Mars, there are still no clear reasons for the planet’s thin atmosphere. According to one theory, the low gravity of Mars, as well as the absence of a magnetic field, has made the atmosphere of this planet vulnerable to the pressures caused by the solar wind. Over millions of years, the pressure of these winds removed light molecules from the Martian atmosphere, thinning it. NASA’s MAVEN probe has been in charge of studying the atmosphere of Mars. According to other hypotheses, the collision with a small object may have led to the destruction of the Martian atmosphere.

The thin atmosphere of Mars and its great distance from the Sun is the reason for its very low temperature compared to Earth. The average temperature on Mars reaches minus 60 degrees Celsius. The temperature of Mars reaches minus 125 degrees Celsius near the poles and 20 degrees Celsius near the equator. Although the Martian atmosphere is much thinner than Earth’s, it is thick enough to retain weather, clouds, and winds. Huge dust storms have caused the surface of Mars to be covered with iron oxide dust. Dust is a stable part of the Martian atmosphere.

A view of Martian clouds captured by the Curiosity rover

Mars is deprived of a global magnetic field, but solar winds produce a type of magnetosphere or magnetosphere through direct reaction with the Martian atmosphere. On the other hand, according to the findings of the InSight probe, the magnetic field at the landing site of this probe is ten times stronger than predicted and fluctuates within a few seconds to several days.

Before the InSight mission, the best estimates of the magnetic fields of Mars were obtained from satellites in the orbit of this planet, whose average distance to Mars was 150 km. Mars had a global magnetic field in the distant past. The InSight magnetic sensor provided new clues about the phenomena of the upper atmosphere and the space environment around Mars. Just like Earth, Mars is exposed to solar winds; But since it lacks a global magnetic field, its protective insulation against the sun is weaker.

According to the researchers, the fluctuations of the magnetic field of Mars during the day and night are caused by the combination of the solar wind and the interplanetary magnetic field around the planet, and the solar rays produce a magnetic field by charging the upper atmosphere and producing electric currents.

Since Mars is farther from the Sun than Earth, its year is longer than Earth. Mars completes the orbit of the Sun during 687 Earth days; Therefore, the Martian year is equal to two Earth years. The length of days on Mars and Earth is almost equal. The rotation of Mars around its axis or a Mars day is 24 hours and 40 minutes. While the earth day is 24 hours.

Like Earth, Mars has different seasons, with the difference that the Martian seasons are usually longer, because the elliptical orbit of Mars around the Sun is a little more elongated than other objects; Therefore, when Mars is at its closest distance to the Sun, its southern hemisphere faces the Sun and experiences a short and hot summer; While a short and cold winter is going on in the Northern Hemisphere. When Mars is farthest from the Sun, its northern hemisphere faces the Sun. In these conditions, a long and moderate summer will flow, while the southern hemisphere will experience a cold and long winter.

American astronomer Asaph Hall discovered two moons of Mars named Phobos and Deimos in August 1877. The HiRISE camera of the Mars Orbiter captured two images of the two largest moons of Mars, Phobos and Deimos, on March 23, 2008. Ninety-four years after Hall’s discovery, the Mariner 9 spacecraft got a better view of the two moons of Mars. The most remarkable feature of Phobos is a ten-kilometer-wide crater that is half the width of the moon itself.

The moons of Mars are among the smallest moons in the entire solar system. Phobos is only slightly larger than Deimos and is located at a distance of 6000 km from the surface of Mars. Phobos orbits Mars once every three days. The more distant moon Deimos completes an orbit of Mars every thirty hours. The rotation direction of Phobos is inward and it gets closer to Mars by 1.6 meters every hundred years. Phobos may hit the surface of Mars in the next 50 million years and form a ring around it after collapsing.

A color-enhanced image of Phobos captured by HiRISE. This photo shows crater chains and grooves on this moon.

If one were to stand on the moon Phobos, one would see Mars occupying more of the sky. In the future, this may become a hobby. According to scientists, in the future, one of the moons of Mars may be used as a base to observe the Red Planet and send a robot to its surface.

Phobos and Deimos, like Earth’s moon, have a tidal lock; Which means that only one side of them can be seen from Mars. Both moons are irregular in shape, full of craters and impact craters covered in dust and small rocks. Phobos and Deimos are the darkest objects in the solar system. These moons are composed of carbonaceous rocks with ice, which may be the result of asteroid collisions.

The gravity of Phobos is one-thousandth of the Earth’s gravity. A person’s weight of 68 kg in Phobos reaches 68 grams. The names of the moons of Mars are derived from the mythological sons of Ares, the Greek counterpart of Mars, the Roman god. Phobos means fear or terror (phobia) and Deimos means escape (fleeing after defeat).

Color-enhanced image of Deimos captured by HiRISE. This image shows the soft and smooth regolith cover of Deimos.

Humans have been seeing strange objects on the Martian surface for centuries. The reason for this issue can be the closeness of the conditions of Mars to host life or maybe Mars is close enough and can be observed more precisely. However, Earthlings were repeatedly fooled by the rocky surface of Mars and their illusions (such as finding channels to human faces and Martian bases); But all these findings turned out to be wrong. Here are some of the wonders of Mars:

According to Sir William Herschel’s notes in 1784, the dark areas of Mars are the oceans and the lighter areas are the Earth. According to the speculations of this famous British astronomer, Mars is surrounded by intelligent beings who probably have the same conditions as Earthlings. Herschel’s theory was the dominant theory for a century and even some astronomers claimed to have seen vegetation on the bright land of Mars. Fortunately, Herschel’s other astronomical achievements led to two powerful observatories being named in his honor. These theories were so strong that the Martian life theory was not very important.

Giovanni Schiaparelli, an Italian astronomer, observed grooves on the surface of the Red Planet during his close observation of Mars in 1877. He used the Italian word canali, which means channel, to describe these grooves and concluded that Mars has intelligent life that made these waterways.

Another astronomer, Percival Lowell, 1895 presented a plan for Martian canals in his book entitled “Mars, the Abode of Life”, which increased the popularity of this misconception. The theory of Martian canals was rejected in the early 20th century. At that time, the channels proved to be just visual errors. When you see Mars with weak telescopes, the point-like features of mountains and impact craters appear continuous, forming smooth lines. By spectroscopic analysis of light received from Mars, it was later proven that there is no water on the surface of this planet.

In 1976, NASA released an interesting image of a Martian mountain captured by the Viking 1 probe. The image showed a face with eyes and a nose. The Martian face inspired numerous myths and conspiracy theories for about thirty years, and many people believed that an ancient Martian civilization had created the face.

From the aerial angle, the shadows of the mountains of Mars look like faces; But from other angles captured by the Mars Express orbiter and other probes, the Martian mountain does not look like a face. Pareidolia is a scientific and psychological term that refers to seeing familiar faces or objects in different places. Facial pareidolia is the result of increased sensitivity to the details of the human face.

Arthur C. Clarke, the famous science fiction writer and author of “2001: A Space Odyssey”, announced seven years before his death that he saw streaks of vegetation, including trees, in new images from the Mars Global Surveyor. Clark says:

It’s like something like vegetation is moving with the seasons. I still hope we can find Martians. The branches and trees that Clark was talking about are actually geologically called “spiders”. These surface phenomena look like branches and change seasonally, But the reason for this is the seasonal melting of carbon dioxide ice covers in the poles of Mars. When the carbon dioxide ice is sublimated, it spreads in the form of branch streaks.

In 2007, the Spirit rover captured an interesting sight on the Red Planet: a person wearing what appears to be a robe and kneeling in prayer. The Spirit rover captured a panoramic image of Home Plate, which is located in the Gosef impact crater in the Columbia Range. Of course, the subject of this image is a stone that looks like a human due to the phenomenon of paridolia.

The face of Mars in 1976 was only the beginning of such illusions. With the launch of Google Mars in 2009, users were able to see the surface of Mars and examine all kinds of roughness. This program was created from a set of compiled satellite images. An Italian man named Matteo Iannio, by examining these images, found a bump that resembled the appearance of Mahatma Gandhi, the Indian independence leader who was killed in 1948. Higher quality images showed that the said image is not related to a mountain or a hill; Rather, it is a pit that looks like a human in profile. The effect of pareidolia can be easily seen in the comparison of low-quality and high-quality images.

In 2011, another piece of evidence for the claim of life on Mars was unveiled. In a viral video on YouTube, someone claimed to have detected a human (extraterrestrial) base on Mars. He called this base “Alpha Biological Station”. Through Google Mars, he identified a linear and mysterious structure on the surface of the red planet.

Astronomers immediately identified a white structure that had become pixelated and of poor quality. This image was created due to the accumulation of cosmic rays in the image sensor of the camera that recorded this image. Alfred Ekayon, a planetary scientist at the Planetary and Lunar Laboratory of the University of Arizona and the head of the Planetary Image Processing Research Laboratory, says this: Such effects are common in space images taken by orbiting telescopes outside the magnetosphere.

The image received by the European Space Agency (ESA) orbiter in 2019 looks like a giant blue-haired spider with its feet on a Martian mountain. The reality is much more interesting. The legs of this spider are actually the paths of hundreds of small tornadoes or devil’s ovens. It is not yet clear why this mountain is the center of tornadoes; But according to ESA scientists, the movement of air masses in this area can lead to the formation of such tornadoes.

It seems that seeing creepy crawlies on Mars has become a hot topic. In 2019, William Romoser, professor emeritus, made an interesting claim. He claimed to have seen cockroaches and other insects and even reptiles on the surface of Mars. After examining the images received from NASA’s Mars rovers, Romoser observed raised shapes and vague ovals on the surface of Mars; But this time, Paridolia tricked him; Because the protruding shapes were mostly stones.

Between July and September 2019, an object, possibly a meteorite or part of a comet, collided with the southern ice cap of Mars, puncturing a thin layer of the ice cap, and releasing red soil from the crater. The result of this incident was the emergence of a large red discharge that resembled cartoon characters hitting the wall. The large HiRISE (High Resolution Imaging Science Instrument) camera on the Mars Reconnaissance Orbiter (MRO) captured the leak, which is up to a kilometer across. This discharge was not a vision error and was completely fixed.

As you know, Mars is a red planet; But what is this strange green stone (pictured below) doing on the red planet? The Perseverance probe captured the image of this rock. The length of this stone reaches approximately 15 cm and it is located in the impact crater of Yezro, which is close to the landing site of Perseverance. The Perseverance rover removed a portion of the rock to vaporize it. The rover’s cameras and spectrometers examined the resulting vapor cloud to reveal its chemical composition. The answer to this mystery will be revealed soon.

Throughout history, Mars has only been observable at the closest distance to Earth. Martian perigee positions (closest to Earth) occur every 15 to 17 years. In the 17th century, Tycho Brahe measured the relative distance between Earth and Mars. The Cassini probe made more measurements. In 1610, Galileo was able to observe Mars with a telescope for the first time. Christian Huygens was also the first person to draw a map of the surface features of Mars. During the 20th century, with the beginning of the space age, observations and explorations increased at a remarkable rate.

So far, many probes have been sent to Mars, but almost one out of three missions were successful. In general, exploration programs pursue four main goals:

• Investigating the existence of Martian life
• Investigating the Martian climate
• Survey of Martian geology
• Preparing for human exploration

In the first Mars missions, which were simply flybys of the planet, spacecraft flew close to the surface of Mars and imaged it. NASA’s Mariner spacecraft was a small robotic probe developed to study the neighboring planets, including Venus, Mars, and Mercury. Mariner 4 passed by Mars in July 1965 and sent the first pictures of this alien world to Earth.

The thin atmosphere of Mars makes it difficult for probes to land

In 1971, the Soviet Union managed to send its first spacecraft into Mars orbit and even sent a lander to touch its surface. The Mars 3 Orbiter also sent back data about the topography, climate, atmosphere, and geology of Mars for eight months. Although the lander of this probe managed to land on the surface of Mars, it lasted only 20 seconds.

Later, the Mariner 9 orbiter sent back more and more detailed images of the Martian atmosphere, mapping its surface, revealing the Martian topography, and capturing many images of this remote and strange world. The above missions solved some mysteries of Mars, including the legend of Martian canals and its ancient civilizations. On the other hand, they raised new questions about ancient Martian riverbeds that could indicate the presence of liquid water on this planet.

The Viking 1 and 2 spacecraft were a pair of orbiters and landers that reached Mars in 1976. These two probes continued to operate until the end of 1982 and surprised scientists by sending images of the surface of Mars. The Viking landers conducted biological experiments on the Martian soil and were supposed to find signs of life, but their results were not enough.

The Mars Rover mission launched in 1996 paved the way for sending rovers. Sojourner, the rover of this spacecraft, sent information about the seasonal changes and weather of Mars, especially dust storms. The Mars Global Surveyor spacecraft has been in orbit since March 1999 with the aim of studying the surface of Mars.

The long-duration mission has provided new data on Mars’ changing seasons and weather, including dust storms. Mars Odyssey orbiter entered Mars orbit in 2001. The gamma-ray spectrometer of this spacecraft managed to discover significant amounts of hydrogen gas within a few meters of the surface of Mars.

The European Space Agency went to Mars in 2003 with the Mars Express probe. This probe was carrying a surface lander called Beagle 2, which disappeared in 2004. Beagle 2 was rediscovered in January 2015 by NASA’s Mars Reconnaissance Orbiter (MRO). During its mission, the Mars Express orbiter managed to discover methane in the Martian atmosphere, which is one of the necessary elements for the formation of life.

In January 2004, NASA landed its twin Mars rovers Sprite and Apchornity on the surface of Mars. Perhaps the most famous Mars missions are the Spirit and Opportunity rovers. These two rovers landed on both sides of Mars in January 2004 and began their extensive mission.

These two rovers examined several kilometers of the Martian soil and sent more than 100,000 high-quality images. They examined Martian rocks and soil and used laboratory modules equipped for geological tests on the Martian surface and subsurface. The mission of these two rovers was designed for 90 days, but they lasted for several years. The Spirit rover was active until 2010, and the Opportunity rover was shut down for good in 2018.

On March 10, 2006, the MRO (Mars Reconnaissance Orbiter) probe entered Mars orbit for two years of exploration. The orbiter began mapping the Martian surface and its climate with the aim of finding suitable landing sites for future missions. The MSL (Mars Science Laboratory) mission was launched on November 26, 2011 to send the Curiosity rover to the surface of Mars. This rover reached Mars on August 6, 2012. Curiosity is more advanced and larger than NASA’s previous rovers, and its maximum speed reaches 140 meters per hour. The rover’s experiments included laser chemical sampling and sending data on the composition of rocks.

Selfie probe Curiosity

The MAVEN orbiter was launched on November 18, 2013, and landed at an altitude of 6,200 km on September 22, 2014, to study the Martian atmosphere. The goals of this mission include investigating the atmosphere and water of Mars in the distant past. The Indian Space Research Organization (ISRO) launched the MOM (Mars Orbiting Mission) spacecraft on November 5, 2013. This spacecraft was placed in Mars orbit on September 24, 2014. ISRO is the fourth space agency to reach Mars after the Soviet Union, NASA, and the European Space Agency.

The TGO orbiter reached Mars from Exomars in March 2016. Schiaparelli’s lander landed on Mars as an experiment. Schiaparelli hit the Martian surface but sent back key data about the parachute landing, so the test can be considered a partial success.

We fully implement the sanctions imposed by our member states against Russia and evaluate the consequences of our current programs that are carried out in cooperation with the Russian Space Agency. In addition, we align our decisions in close coordination with industrial and international partners (especially with NASA and in the International Space Station program) and the decisions of the member countries of the organization.

Dmitry Rogozin, the head of Russia’s space agency, reacted quickly on Twitter, claiming that Isa was self-harming out of anger. If ExoMars is not launched in 2022, it will have to wait another two years until the next opportunity; Because it is only at that time that Mars and Earth are in the closest position to each other. In August 2012, NASA selected the $425 million InSight lander to explore the depths of the Martian surface. Two CubeSats named MarCO were launched together with InSight on May 5, 2018. The CubeSats separated 1.5 hours after launch and started their paths. The InSight probe successfully landed on the surface of Mars on November 26, 2018.

The Perseverance rover was launched from the Mars 2020 mission on July 30, 2020. This probe landed on the surface of Mars on February 18, 2021. Perseverance was also accompanied by a helicopter named Ingenuity. Twelve months later, Perseverance reached the mouth of Yezro, 45 km away. Based on the topography, it is clear that more than three billion years ago, Yezero was a body of water the same size as Lake Tahoe in America, and rivers flowed from the west and east of it. One of Perseverance’s first missions was to launch Ingenuity, a small robotic helicopter. Ingenuity is the first spacecraft to lift off from the surface of another planet. Perseverance also demonstrated the performance of oxygen generation technology, which is essential for manned missions to Mars.

In the next step, Perseverance investigated the bed of the Yazoro crater and it was found that the rocks of this crater are far from the expectations of scientists. Perseverance had trouble collecting stone cores several times. The rover will mine rock material in cylinders about the size of chalkboard chalk that will be returned to Earth on future missions. Ingenuity was one of the last additional parts of the mission, which was intended to prove the feasibility of flying in the thin air of Mars. On April 18, 2021, Igneoti soared to a height of three meters, flew for 30 seconds, and then returned to the ground. This flight lasted a total of 39.1 seconds.

The Ingenuity helicopter is preparing for its first flight.

Ingenuity’s mission was supposed to end after four flights; because Perseverance should have abandoned it and continued scientific research; But NASA decided that five flights were not enough. As Perseverance began exploring the rocks to the south, Ingenuity’s helicopter accompanied it and surveyed the terrain ahead of the rover. Thus, the rover’s time is not wasted by hitting unexpected rocks.

Perseverance surprised scientists by examining and excavating rock samples south of its landing site. Perseverance’s instruments to examine the materials that makeup Martian rocks examine their tiny grains, which are as small as a grain of sand. The cameras on the robotic arm can also record close-up images. In the observations, large olivine particles were seen; An igneous rock mineral that can accumulate in the bed of a large lava flow. Other pieces appeared between the olivine particles that were filled with carbonate; A mineral that is formed by reacting with water.

Perseverance is the first step of mankind in realizing the dream of bringing Mars samples to Earth. This probe creates holes in the rocks and holds them in insulated pipes. Since Perseverance has no way to send rock samples back to Earth, another spacecraft will have to send them home later. This mission is called “Mars Sample Return” and is a joint project of NASA and the European Space Agency.

Image gallery of Mars exploration missions

Human exploration of Mars has had many supporters since the early days of the space age. Robert H. Goddard used the idea of ​​a trip to Mars as an incentive to study physics and aerospace engineering. Various proposals for human exploration of Mars have been presented throughout the history of the space age. Currently, active plans and programs to send humans to Mars in the next ten to thirty years have been presented at the government and private levels.

In 2004, the then President of the United States, George W. Bush, announced the program of human exploration of Mars. Urine spacecraft will be used to send space crews to the moon by mid-2020. In the next phase, the moon will become a way station for the journey to Mars. On September 28, 2007, then NASA administrator Michael D. Griffin announced that he would send humans to Mars by 2037. On October 8, 2015, NASA released the official plan for Mars exploration and colonization. They named this project “Journey to Mars”. This plan has three stages to sustainable colonization.

• The first phase that is being implemented is called the “ground-dependent” phase. At this stage, until 2024, the International Space Station will be used to evaluate technologies and investigate the effects of long-duration space missions on the human body.
• In the second stage, titled “Proof Field”, the dependence on the Earth will be removed and for most of the tasks, the space of Cis Luna (Moon orbit to the surface of the Moon) will be used.
• The final phase, the “Earth-independent phase,” involves long-duration missions to the lunar surface. At this stage, the resources of Mars are used for fuel, water, and building materials. NASA’s goal is to send humans to Mars by the mid-2030s, although independence from Earth may be a little later.

The long-term goal of the private company SpaceX is to plan space flights to Mars and colonize the planet. To achieve this goal, this company is developing a spacecraft called Starship, which is capable of transporting crew to Mars and other solar system objects. In 2017, SpaceX announced plans to send two unmanned starships to Mars by 2022, followed by two more unmanned and manned starships in 2024. Starship is supposed to carry at least 100 tons of cargo.

Starship SN15 and SN16

Mars is a harsh environment for human life. In the long term, various technologies have been developed to aid long-term space exploration, and these technologies may be used for Mars as well. The longest duration of human stay in space is 438 days recorded by Valery Pliakov. The longest time spent outside Earth’s Van Allen Belt is about 12 days, dating back to the Apollo 17 moon landing. This period is very short compared to NASA’s 1,100-day journey in the next decade. On the other hand, according to scientists, traveling to Mars will have harmful biological effects on the human body. Due to the high radiation, the physical effects of living on Mars are increased.

Many missions to Mars are being developed and planned that will pave the way for human travel. Scientists hope the robotic probes will send back data about underground activity as well as the geology of Mars and take samples. Such missions could discover more signs of life and water on the planet. Maybe life is hidden under the layers of the Martian surface.