Recently, in one of the images of the Curiosity rover, which NASA published on its official website, a silhouette resembling the figure of a woman was discovered. Let's remember other similar cases. 1. Silhouette of a woman
The silhouette of a woman looks very believable, the "ghost" seems to be standing on a stone, demanding attention - Hey, I'm here! 2. Martian man
The Curiosity rover has photographed the Martian cliffs and in this image, a giant crab with ten legs is clearly visible. The find excited the society and thousands of people, turned to NASA with a request to return the device to this rock in order to try to find this alien crustacean there. NASA ignored the request, claiming that it was the result of crossover - a feature of the brain that allows people to see familiar shapes in random objects. 10. Flying balls
Ancient Chinese astronomers called Mars the "Fire Star", and scientists will "burn" curiosity about some things related to the Red Planet for a long time. Even after dozens of spacecraft were sent to Mars for exploration, many questions remained unanswered.
Why does Mars have two "faces"?
Scientists have been puzzled for decades by the difference between the two sides of Mars. The northern hemisphere of the planet - smooth and low - is one of the smoothest and flattest places on the planets of the solar system. It could potentially have formed from the water that once splashed on the Martian surface. At the same time, the southern half of Mars is uneven and all cut with craters. It is about 4-8 kilometers higher than the northern part. Recent studies suggest that such differences between the southern and northern sides of the planet could be associated with a giant space body, which may have once fell to the surface of Mars.
What is the source of methane on Mars?
Methane, the simplest organic molecule, was first discovered in the atmosphere of Mars by the European Space Agency's Mars Express spacecraft back in 2003. On Earth, most methane is produced by living organisms such as cattle, which digest food. Methane is believed to be stable in the Martian atmosphere for only 300 years, but who or what could have generated this gas so recently remains a mystery.
Still, there are ways of methane formation without the participation of living organisms, for example, volcanic activity. Launched in 2016, the European Space Agency's new Exomars program will study the chemical composition of Mars' atmosphere so scientists can learn more about Martian methane.
Does Mars have liquid water?
While a large body of evidence indicates that there was once liquid water on Mars, whether it exists today remains a mystery. The atmospheric pressure on Mars is very low, about 100 times less than the pressure on Earth, so liquid water is unlikely to remain on the surface of the Red Planet. However, the dark, long lines that we can see on the surface of Mars hint that salty streams of water may flow through them every spring.
Did Mars have oceans?
A large number of Martian missions have shown that there are many signs on Mars that water once splashed on the planet's surface. It looks a lot like there were oceans, networks of valleys, river deltas, and minerals that could form water.
However, modern models of the early Martian climate cannot explain how such high temperatures could exist on the planet to form liquid water, since the sun warms the planet's surface much weaker. Could it be that some of the surface features could have been formed not by water but by winds or other mechanisms? However, everything indicates that ancient Mars was still warm, and there could be water on its surface, at least on one side of it. However, some scientists claim that ancient Mars was cold but humid, although this theory continues to be disputed.
Is there life on Mars?
The first spacecraft that successfully landed on the surface of Mars - NASA Viking 1 - was the first to try to reveal the secret about whether there is life on the Red Planet, but so far no answer has been received to this question. Today this question worries researchers of Mars all over the world. Viking discovered organic molecules such as methyl chloride and dichloromethane. However, later it turned out that these were terrestrial impurities that were part of the cleaning fluids when preparing the device on Earth.
The surface of Mars is quite suitable for the appearance of life on it, as far as we know, since there are appropriate conditions: suitable temperature, radiation, increased dryness and other factors. There are a huge number of examples when life appeared on Earth in even more severe conditions, for example, in the far north, in the dry soils of the Antarctic Dry Valleys and in the very dry Atacama Desert in Chile.
Where there is liquid water on Earth, life is everywhere, so scientists believe that if there is water on Mars, there must certainly be life. When scientists answer the question whether there is life on Mars, they will be able to shed light on a number of other questions that remain unanswered today, for example, may or may not life originate in other parts of the universe.
Life on Earth came from Mars?
The meteorites that were discovered in Antarctica came to our planet from Mars. They broke away from the Red Planet during its collisions with other space objects. These meteorites have structures that resemble those created by earth microbes. Although many studies suggest that these structures are most likely obtained by chemical means, the controversy in the scientific world continues. Some researchers believe that life was brought to Earth from Mars a long time ago, and it was meteorites that could have brought it here.
Can earthlings live on Mars?
In order to finally answer the question whether there is life on Mars or not, a person can fly there and find out.
Back in 1969, NASA had plans to organize a mission to send a man to Mars by 1981, in order to establish a permanent Mars station there by 1988. However, interplanetary travel with human participation turned out to be not such an easy task from both scientific and technical points of view.
For example, significant difficulties were: ensuring a supply of food, water, oxygen, eliminating the harmful effects of microgravity and radiation, reducing the likelihood of fires to zero, and so on. But the most important thing is that you need to psychologically adjust a person to the fact that for many years he will be far from the Earth and from real help. It is also difficult to imagine how you can organize landing, work, life on an alien planet and return from there back to Earth.
Nevertheless, astronauts have long dreamed of such flights. For example, volunteers agreed to live on a spaceship for about a year. It was the longest space flight simulation ever developed, the goal of which was to reproduce in terrestrial conditions what a mission to Mars could be from start to finish.
There are a great many volunteers willing to go to Mars. Perhaps someday such a flight will become a reality.
Recently, on one of the images of the Curiosity rover, which NASA published on its official website, ufologists discovered a silhouette resembling a woman's figure.
Let's take a closer look at this and other similar cases.
Ghost woman
The silhouette looks so believable that for some it may be the embodiment of a desire to find extraterrestrial life. The picture is complemented by the fact that the "ghost" seems to be standing on a stone, demanding attention.
Yeti
The legendary find of the Spirit rover. Photo of 2008, which shows the silhouette of a creature, as it were, wandering through the red desert. Due to the fact that his pose reminded of the famous shot, where the Bigfoot was allegedly captured, the mysterious stranger was nicknamed the "Martian Yeti".
Alien Temple
A snapshot of the 2008 Mars rover Opportunity, in which the layered rock reminded ufologists of the creation of human (or alien) hands. The hoaxers suggested that the frame captures the entrance to the destroyed temple with a large monument that meets visitors. The "Martian ship" immersed in the sand was also discovered nearby. 
Trees
This 2011 image from the Reconnassance Orbiter space station has a fairly simple scientific explanation. Firstly, if these were trees, then, judging by the image, they would grow parallel to the surface of the planet. Secondly, such marks in the sand are the result of the evaporation of frozen carbon dioxide. 
Temple face
A legendary photo that excited the minds of people in the late seventies and early eighties. Then many decided that some civilization had built a temple in the shape of a human face on Mars.
Giant emoticon
In 1976, the Viking Orbiter 1 spacecraft discovered a giant smiley face on Mars. In 1999, with clearer shots, scientists were able to take a closer look. We are talking about a crater with a radius of 230 kilometers. The find was later used in the famous Guardians comic.
Ball
In September 2014, the Curiosity rover sent a snapshot of a flawless ball lying on the planet's surface. However, NASA quickly cooled the fervor of ufologists: the size of the "artifact" is about one centimeter in diameter, and it turned out, most likely, as a result of a geological process called a nodule. During it, something like a snowball is formed around some small solid body.
Small helmet, bone and a Martian rat
No, these are just stones. 
Flash Light
The Curiosity snapshot, taken in April 2014, gave ufologists a reason to assume that aliens accidentally gave themselves away with a flash in the dark. However, NASA scientist Doug Ellison dispelled the myth, suggesting that we could talk about the impact of a cosmic ray - a stream of charged particles.
Drawing on the ground
The only real artificial artifact on Mars is the footprints left by the Curiosity rover. 
Just a couple of days ago, in one of the pictures, a mysterious find, the "Martian crab", was again discovered. These photos, posted on the official NASA website, spread throughout the media and other sources of information and caused a lot of controversy. We present you a video about this photo.
Mars was known to ancient Chinese astronomers as the "red star" or "fire star". Unsurprisingly, scientists are still burning with questions regarding the Red Planet. Even after dozens of spacecraft have been sent to its surface and into its orbit, Mars remains unknown and mysterious to us earthlings. Below I have compiled the most exciting unsolved mysteries of this planet.
Why does Mars have two faces?
Scientists have been puzzling over the differences between the two sides of Mars for decades. In the northern hemisphere, the planet's surface is smooth and low-lying, making it one of the flattest and smoothest places in the solar system. It is believed that in this part of the planet there was once a large accumulation of water, for example, the ocean. Meanwhile, the southern hemisphere of Mars, on the contrary, is very heavily riddled with craters, and 4 to 8 km higher than the northern one. Recent evidence suggests that such strong differences were caused by a collision with a huge celestial body in the distant past of Mars.
Where does methane come from on Mars?
Methane, the simplest organic molecule, was first discovered in the atmosphere of Mars by the European Space Agency's Mars Express spacecraft in 2003. On Earth, for example, most of the atmospheric methane comes from living organisms, such as cattle, which digest plant foods. Scientists believe that it has been stably present in the Martian atmosphere only for the last 300 years, so whatever produces it, it does so quite recently. Although, there are methods of methane formation that are not related to organic life, such as, for example, volcanic activity. ESA's ExoMars spacecraft, which is slated to launch in 2016, will study the chemical composition of the Martian atmosphere specifically to determine the source of methane.
Is there liquid water on the surface of Mars now?
While there is ample evidence that liquid water once flowed across the surface of Mars, it remains an open question, is it flowing anywhere on the Red Planet now? Atmospheric pressure on the planet is too low (about 1 / 100th of the Earth's) for water to remain in liquid form. However, the dark, narrow lines that are clearly visible on the Martian slopes give hope that they were left by the streams of liquid water in the spring.
Were there oceans on Mars?
Numerous missions to Mars have revealed many signs that the Red Planet was once warm enough for water to exist in its liquid phase. These features include vast ocean beds, networks of depressions, river deltas, and minerals that require water to form. However, modern computer models of the climate of young Mars cannot explain how such high enough temperatures could exist at that time, since the sun was then much weaker, so some researchers believe that these features could be created by winds or some other way.
Is there life on Mars?
The first spacecraft to successfully land on Mars, Viking 1, posed a riddle for all of us that remains unsolved to this day. Is there life on Mars? Viking discovered organic molecules on the planet such as methyl chloride and dichloromethane. However, these compounds were considered the result of pollution from the Earth, namely, as a result of cleaning fluids used to prepare spacecraft. The surface of Mars is very hostile to life as we know it. Cold, increased radiation, lack of water and other factors. However, there are numerous examples of life in extreme conditions on Earth, such as Antarctica or the Atacama Desert in Chile. Life exists almost everywhere there is liquid water on Earth. And the possibility that Mars once had oceans makes many hope that life once did develop on Mars, which means it may have survived. The answer to this question can help shed light on whether life is possible in the rest of the universe.
Did life on Earth begin on Mars?
The meteorites from Mars found in Antarctica have traces and blotches that resemble those left in the rock by microbes on Earth. Although many researchers believe that the nature of the emergence of these structures is chemical, and not biological, disputes are still ongoing, and it is in them that the truth is born. This is especially interesting because Mars could become the homeland of life on Earth, through meteorites.
Can humans live on Mars?
To answer the question whether there was or is there life on Mars, people still have to go there sooner or later. By the way, NASA was planning back in 1969 a manned mission to Mars by 1981 and a permanent base on Mars by 1988. Not lagging behind, and in many respects ahead of the Soviet Union. However, interplanetary human flight has certain scientific and technological difficulties. The provision of food, water and oxygen, the harmful effects of zero gravity, the potential hazards of fire and radiation, and the fact that with such hazards, astronauts are millions of kilometers away from help. Nevertheless, there have always been daredevils, and even now there is no shortage of them. For example, this year, six volunteers lived in conditions simulating space travel for nearly a year and a half as part of the so-called Mars500 project. It was the longest running space flight simulation experiment ever conducted. There are even numerous volunteers for a one-way trip to the Red Planet and founding a colony there. So maybe soon we will find answers to all these mysteries of the Red Planet. And most likely, along with the answers, we will receive even more questions, as is the case with our native Earth.
Hundreds of NASA scientists and engineers continue to supervise the Opportunity and Curiosity rovers. High-tech chemical laboratories on wheels daily send information about the planet to Earth, to which it is planned to send the first expedition, which will include people, in a relatively short time.
At the moment, the estimated period of active operation of devices on the surface of Mars has long expired, however, thanks to the genius of their creators, the rovers continue to work for the good of mankind to this day, from time to time throwing scientists the most complex riddles.
While the luminaries of science try to find a logical explanation for the mysteries of the fourth planet, conspiracy theorists and ufologists often use the extracted materials to announce evidence of the existence of extraterrestrial intelligence.
Opportunity and the jelly donut puzzle
The scope of work on the Opportunity rover in 2014 was comparatively insignificant. The reason for this is the long service life of the robot on the surface of Mars, which it touched on January 25, 2004.Then scientists called the effective life of the apparatus 90 sol (Martian days, which last a little longer than Earth's), but the successful design of the rover and innovative technologies allow it to collect information to this day. It was Opportunity that proved that fresh water existed on Mars in the distant past, which formed river channels.
Opportunity prepares to celebrate its 11th anniversary on Mars
Photo: mars.nasa.gov
During its work on Mars, Opportunity has worn out, some of its equipment has failed, so the rover is practically standing still. However, on January 8, 2014, the robot still managed to drive into a dead end its engineers, as well as that part of the Earth's population that monitors the research of the neighboring planet.
In the picture, which the device sent, right next to the rover, which was not there a few days ago.
A strange stone discovered by scientists in one of the images of Opportunity
Photo: space.com
While the geologists and project engineers were trying to figure out the reasons for the appearance of an unknown object near Opportunity, the news had already scattered across the Web, giving rise to a heated discussion of the event. Some Internet resources related to ufology immediately tried to explain the appearance of a strange stone as evidence of the presence of intelligent life on Mars, as well as to convict NASA of hiding evidence.
Steve Squires (lead scientist of the Opportunity project) added fuel to the fire with his joke at one of the presentations when he said that the discovered stone looks like a "jelly donut". This gave rise to another wave of humor on the Internet, and some managed to take the statement seriously.
After some time, NASA employees were still able to explain the reasons for the appearance of an unknown object next to the rover. When the scientists managed to move the car a short distance, the cameras examined the area under it and found a rock nearby, from which a small pebble fell off. This happened, most likely, at a time when the Opportunity chassis skidded in an attempt to move the vehicle.
Photo: jpl.nasa.gov
However, the scientists did not experience much disappointment, because the chemical composition of the found stone turned out to be extremely interesting for geologists and allowed them to draw several conclusions about the concentration of substances in the rock of Mars under the influence of water currents.
Curiosity: 28 months on Mars
Like Opportunity, the third-generation rover Curiosity has already crossed its planned lifetime on Mars. At the same time, the apparatus continues its research mission.For two and a half years of work on a neighboring planet, the robot has collected a large amount of information that scientists need to ensure the safety of interplanetary flights for the human body, as well as living on the surface of an alien planet.
Recently, The New York Times published a video "28 months on Mars", dedicated to the work of the rover on the Red Planet. The creators have compiled a two-minute video from footage taken by Curiosity himself during his stay on Mars, starting on August 6, 2012. The last picture is dated December 3, 2014, at 827 sol of the device's operation.
During the routine work of exploring the surface of Mars, Curiosity often witnesses mysterious events that baffle NASA scientists.
Curiosity's strange glow and the theory of the Martians
On April 3, on the NASA website, on which a strange white spot can be seen with the naked eye, most of all similar to light of artificial origin.The first to notice this was the American ufologist Scott Waring, who hastened to post the photo on his resource. The ufologist argued that the strange glow, in his opinion, was not a sun glare or a graphic artifact in the photograph, opaquely hinting that aliens were involved in the case. Here Waring accused NASA scientists of the fact that they could "ride" on the rover to the source of the strange glow, but deliberately inhibit the study and do not try to find life on Mars.
The mysterious glow in one of the Curiosity photographs has caused a lot of controversy among astronomy enthusiasts.
Photo: NASA
While less radical readers on the Internet joked that the Martians managed to unscrew the "spare" from the rover and now they are burning tires over the hill, scientists from the NASA laboratory tried to explain to the public that such artifacts in photographs are not uncommon.
Doug Ellison, who is one of the JPL employees, explained on his Twitter that the appearance of this glow in the image is caused by cosmic rays. This theory is confirmed by the fact that the artifact is only in the image taken from the right lens of the Navcam system, while the left "eye" did not record an anomaly.
Finding the first possible signs of life on Mars
In December 2014, a message appeared on the NASA website that Curiosity had a short-term abnormal increase in the concentration of methane in the atmosphere near the probe. For scientists, such data may be the main evidence of the existence of life on Mars, but they are prudently slow to draw conclusions and continue to analyze the data.Methane emissions were recorded twice - in late 2013 and early 2014, at which time the concentration of gas near the rover was ten times higher than normal. If we take into account the fact that almost all microorganisms on our planet produce methane in the course of their vital activity, then such a discovery could become sensational and radically change the method of Mars exploration.
Curiosity's second discovery excited scientists even more. When a robot extracted samples from a rock called Cumberland and analyzed them chemically, organic compounds containing carbon and hydrogen were found in the rock - the main building blocks of life on our planet.
The researchers reacted to such information with suspicion, since the molecules could have been brought to the surface of Mars by the Curiosity itself. It took many months to verify the data, and only now scientists have published the results and confidently stated that organic compounds are of Martian origin.
Hole in Cumberland Rock. It was from it that a rock sample with organic compounds was obtained.
Photo: NASA
Of course, hydrocarbons can exist separately from organic forms, but such a discovery gives scientists great hopes for the discovery of life outside our planet.
Despite the fact that in the circles of conspiracy theorists there are still theories according to which none of the rovers ever reached the Red Planet, and all the pictures were allegedly taken in the Nevada desert, the crowns of the technical evolution of mankind work tirelessly on an alien planet every day. Small robots are gathering information for those earthlings who, as expected, will soon set off the first manned expedition to Mars.