Are giant squids really just a legend? Does the Kraken live in the Sea of Kraken? What life forms could we find on Titan? Did the Kraken really exist?
In the dark, uncharted sea waters at great depths live mysterious creatures that have terrified sailors since ancient times. They are secretive and elusive, and are still poorly understood. In medieval legends they are represented as monsters that attack ships and sink them.
According to the sailors, they look like a floating island with huge tentacles that reach the peak of the mast, bloodthirsty and ferocious. In literary works, these creatures received the name “krakens”.
The first information about them is found in the Viking chronicles, which speak of huge sea monsters attacking ships. There are also references to krakens in the works of Homer and Aristotle. On the walls of ancient temples you can find images of a monster dominating the sea. Over time, references to these creatures have become less numerous. However, by the middle of the 18th century, the world again remembered the storm of the seas. In 1768, this monster attacked the English whaling ship Arrow; the crew and ship miraculously escaped death. According to the sailors, they encountered a “small living island.”
In 1810, the British ship Celestine, sailing on the Reykjavik-Oslo voyage, encountered something reaching a diameter of up to 50 meters. It was not possible to avoid the meeting, and the ship was severely damaged by the tentacles of an unknown monster, so it was necessary to return back to the port.
In 1861, the kraken attacked the French ship Adekton, and in 1874 sank the English Pearl. However, despite all these cases, the scientific world considered the giant monster to be nothing more than fiction. Until in 1873 he received material evidence of its existence.
On October 26, 1873, English fishermen discovered some huge and presumably dead sea animal in one of the bays. Wanting to find out what it was, they swam up to it in a boat and poked it with a hook. In response to this, the creature suddenly came to life and wrapped its tentacles around the boat, wanting to pull it to the bottom. The fishermen managed to fight back and get a trophy - one of the tentacles, which was transferred to the local museum.
A month later, another octopus 10 meters long was caught in the same area. So the myth became reality. 
Previously, the likelihood of encounters with these deep-sea inhabitants was more real. However, recently we have hardly heard about them. One of the latest events associated with these creatures dates back to 2011, when the American yacht Zvezda was attacked. Of the entire crew and people on board, only one person was able to survive. The tragic story of “Zvezda” is the last known case of a collision with a giant octopus.
So, what is this mysterious ship hunter?
There is still no clear idea of what species this animal belongs to; scientists consider it a squid, an octopus, and a cuttlefish. This deep-sea inhabitant reaches several meters in length; presumably, some individuals can grow to gigantic sizes.
Its head is cylindrical with a chitinous beak in the middle, which it can use to bite through steel cables. The eyes reach 25 cm in diameter.
The habitat of these creatures extends throughout the World Ocean, starting their journey from the deep waters of the Arctic and Antarctica. At one time it was believed that their habitat was the Bermuda Triangle, and they were the culprits behind the mysterious disappearances of ships in this place.
Hypothesis of the appearance of the Kraken
Where this mysterious animal came from is still not known. There are several theories about its origin. That this is the only creature that survived the environmental catastrophe of the “time of the dinosaurs.” That it was created during Nazi experiments at secret Antarctic bases. That perhaps this is a mutation of an ordinary squid or even an extraterrestrial intelligence.
Even in our time of advanced technology, little has been studied about krakens. Since no one saw them alive, all individuals exceeding 20 m were found exclusively dead. In addition, despite their enormous size, these creatures successfully avoid being photographed and videotaped. So the search for this deep-sea monster continues... 
The mythological giant received its name from Icelandic sea travelers who claimed to have seen a huge sea monster similar to. Ancient sailors blamed krakens for the mysterious disappearance of ships. In their opinion, the sea monsters had enough strength to drag the ship to the bottom...
Does the kraken really exist and why is meeting this mythical monster dangerous? Or are these just tales of idle sailors, inspired by too wild a fantasy?
Opinion of researchers and eyewitnesses
The first mention of a sea monster dates back to the 18th century, when a naturalist from Denmark named Erik Pontoppidan began to convince everyone that the kraken really existed. According to his description, the size of the creature is equal to an entire island, and with its huge tentacles it can easily grab even the largest ship and drag it along with it. The greatest danger is the whirlpool that forms when the kraken sinks to the bottom.
Pontoppidan was sure that it was the kraken that led sailors off course and caused confusion during their travels. This idea was brought to him by numerous cases when sailors mistakenly mistook the monster for an island, and when they visited the same place again, they no longer found a single piece of land. Norwegian fishermen claimed that they once found the discarded carcass of a monster of the deep sea on the shore. They decided it was a young kraken.
There was a similar case in England. Captain Robert Jameson had a chance to talk about his meeting with a huge mollusk under oath in court. According to him, the entire crew on the ship watched in fascination as the incredible size of the body rose above the water and then sank again. At the same time, huge waves formed around. After the mysterious creature disappeared, it was decided to swim to the place where it was seen. To the surprise of the sailors, there was only a large amount of fish.
What scientists say
Scientists have no clear opinion about the kraken. Some included the mythical monster in the classification of sea creatures, others rejected its existence altogether. According to skeptics, what the sailors saw near Iceland is the usual activity of underwater volcanoes. This natural phenomenon leads to the formation of large waves, foam, bubbles, and swellings on the surface of the ocean, which is mistakenly mistaken for an unknown monster from the depths of the sea.
Scientists believe that it is impossible for such a huge animal as the kraken to survive in ocean conditions, since its body would be torn apart by the slightest storm. Therefore, there is an assumption that the “kraken” is a cluster of mollusks. If we take into account the fact that many species of squid always move in whole schools, then it is quite possible that this is also typical for larger individuals.
It is believed that in the area of the mysterious 
The Bermuda Triangle has been settled by none other than the largest kraken. It is assumed that he is the one to blame for the people.
Many believe that krakens are demonic creatures, peculiar monsters from the depths of the sea. Others endow them with intelligence and... Most likely, each version has a right to exist.
Some sailors swear that they have encountered huge floating islands. Some ships even managed to pass through such a “ground”, since the ship cut through it like a knife.
Back in the century before last, fishermen from Newfoundland discovered the stranded body of a huge kraken. They hastened to report this. The same news came several times over the next 10 years from different coastal areas.
Scientific facts about krakens
The sea giants received official recognition thanks to Addison Verrill. It was this American zoologist who was able to draw up an accurate scientific description of them and allowed the legends to be confirmed. The scientist confirmed that krakens belong to mollusks. Who would have thought that the monsters that terrified the sailors were relatives of ordinary snails.
The body of the sea octopus has a grayish tint and consists of a substance similar to jelly. The Kraken resembles an octopus, as it has a round head and a large number of tentacles covered with suction cups. The animal has three hearts, blue blood, internal organs, and a brain in which the nerve nodes are located. Huge eyes are designed almost the same as those of a person. The presence of a special organ, which is similar in action to a jet engine, allows the kraken to quickly move over long distances in one jerk.
The size of the kraken is a little different from the legends. After all, according to the descriptions of the sailors, the monster was as big as an island. In fact, the body of a giant octopus can reach no more than 27 meters.
According to some legends, krakens guard the treasures of sunken ships at the bottom. A diver who is “lucky enough” to find such a treasure will have to make a lot of effort to escape from the enraged kraken.
Stories constantly appear about the Kraken, which are full of fiction. For example, it is assumed that there is such a creature as the Great Kraken, living in the Bermuda Triangle. Then the fact that ships disappear there becomes understandable.
Who is this Kraken? Some consider him an underwater monster, some - a demon, and some - a higher mind, or supermind. However, scientists still received true information at the beginning of the last century, when real krakens ended up in their hands. Until that moment, it was easier for scientists to deny their existence, because until the 20th century they only had eyewitness stories to think about.
Does the kraken really exist? Yes, this is a real organism. This was first confirmed at the end of the 19th century. Fishermen fishing near the shore noticed something very bulky, firmly grounded. They made sure that the carcass was not moving and approached it. The dead kraken was taken to the science center. Over the next decade, several more similar bodies were recovered.
They were first studied by Verrill, an American zoologist, and the animals owe their name to him. Today they are called octopuses. These are terrible and huge monsters, they belong to the class of mollusks, that is, in fact, relatives of the most harmless snails. They usually live at depths from 200 to 1000 meters. Somewhat deeper in the ocean live octopuses 30-40 meters long. This is not an assumption, but a fact, since the actual size of the kraken was calculated from the size of the suckers on the skin of whales.
In the legends they spoke about it like this: a block erupted from the water, engulfed the ship with tentacles and carried it to the bottom. It was there that the kraken from legends fed on drowned sailors.
Kraken is an ellipsoidal substance, made of a jelly-like substance, shiny and having a grayish, transparent color. It can reach 100 meters in diameter, while it practically does not react to any stimuli. She doesn't feel pain either. It is, in fact, a huge jellyfish, similar in appearance to an octopus. It has a head and a large number of very long tentacles with suckers in two rows. Even one kraken tentacle can destroy a ship.
There are three hearts in the body, one main, two gills, as they drive blood, which is blue, through the gills. They also have kidneys, liver, and stomach. The creatures do not have bones, but they have a brain. The eyes are huge, complexly arranged, approximately like those of a person. Sense organs are well developed.
Marine life is very diverse and sometimes frightening. The most bizarre forms of life can lurk in the abyss of the seas, because humanity has still not been able to fully explore all the expanses of water. And sailors have long had legends about a powerful creature that is capable of sinking an entire fleet or convoy with just its appearance. About a creature whose appearance inspires horror, and whose size makes you freeze in amazement. About a creature the likes of which have never been seen in history. And if the sky above the world belongs to and, the earth under our feet also belongs to the Tarascans, then the expanses of the seas belong to only one creature - the kraken.
What does a kraken look like?
To say that the kraken is huge would be an understatement. For centuries, the kraken resting in the depths of the waters can reach simply unimaginable sizes of several tens of kilometers. He is truly huge and scary. Outwardly, it is somewhat similar to a squid - the same elongated body, the same tentacles with suction cups, the same eyes and a special organ for moving underwater using air propulsion. But the sizes of a kraken and an ordinary squid are not even close to comparable. Ships that disturbed the peace of the kraken during the Renaissance sank from just one strike of the tentacle on the water.
The Kraken is mentioned as one of the most terrifying sea monsters. But there is someone to whom even he must obey. It is called differently in different nations. But all the legends say the same thing - this is the God of the seas and the ruler of all sea creatures. And it doesn’t matter what you call this super creature - one of his orders is enough for the kraken to throw off the shackles of a hundred-year sleep and do what he was assigned.
In general, legends often mention a certain artifact that gave a person the ability to control the kraken. This creature is by no means lazy and absolutely good-natured, unlike its owners. Without orders, a Kraken can sleep for centuries, or even millennia, without disturbing anyone with its awakening. Or it can change the appearance of an entire coast in a few days if its peace is disturbed or if an order is given to it. Perhaps, among all creatures, the kraken has the greatest power, but also the most peaceful character.
One or many
You can often find references to the fact that there are many such creatures in the service of the Sea God. But it’s very hard to imagine that this is true. The huge size of the kraken and its strength make it possible to believe that this creature can be on different ends of the earth at the same time, but it is very difficult to imagine that there are two such creatures. How terrifying could a battle like this be?
In some epics, there are references to battles between krakens, which suggests that to this day almost all krakens died in these terrible battles, and the Sea God commands the last survivors. A creature that does not produce offspring, free to eat and rest, has reached such enormous dimensions that one can only wonder how hunger has not yet driven it to land and why it has not yet been encountered by researchers. Perhaps the structure of the kraken's skin and tissues makes it impossible to detect it, and the creature's hundred-year sleep hid it in the sands of the seabed? Or maybe there is a depression left in the ocean, where researchers have not yet looked, but where this creature is resting. We can only hope that even if it is found, the researchers will be smart enough not to awaken the wrath of the thousand-year-old monster and not try to destroy it with the help of any weapons.
On the left side of the image you can see a mosaic of images taken by the Cassini spacecraft in the near-infrared range. The photo shows the polar seas and sunlight reflecting off their surface. The reflection is located in the southern part of the Kraken Sea, the largest body of water on Titan. This reservoir is not filled with water at all, but with liquid methane and a mixture of other hydrocarbons. On the right side of the image you can see images of the Kraken Sea taken by Cassini's radar. Kraken is the name of a mythical monster that lived in the northern seas. This name seems to hint at the hopes astrobiologists have for this mysterious alien sea.
Could life exist on Saturn's large moon Titan? This question is forcing astrobiologists and chemists to think very carefully and creatively about the chemistry of life and how it might differ on other planets from the chemistry of life on Earth. In February, a team of Cornell University researchers, including chemical engineering graduate student James Stevenson, planetary scientist Jonathan Lunin, and chemical engineer Paulette Clancy, published a groundbreaking paper suggesting that living cell membranes can form in the exotic chemical environment present on this amazing satellite.
In many ways, Titan is Earth's twin. It is the second largest moon in the solar system and is larger than the planet Mercury. Like Earth, it has a dense atmosphere, the pressure of which at the surface is slightly higher than on Earth. Apart from Earth, Titan is the only object in our solar system that has accumulations of liquid on its surface. NASA's Cassini spacecraft discovered an abundance of lakes and even rivers in Titan's polar regions. The largest lake or sea is called the Kraken Sea, its area exceeds the area of the Caspian Sea on Earth. From observations made by the spacecraft and the results of laboratory experiments, scientists have determined that Titan's atmosphere contains many complex organic compounds from which life is built.
Looking at all this, one might get the impression that Titan is an extremely habitable place. The name “Kraken,” the name given to the mythical sea monster, reflects the secret hopes of astrobiologists. But Titan is the alien twin of the Earth. It is almost 10 times further from the sun than Earth, and its surface temperature is a chilling -180 degrees Celsius. As we know, water is an integral part of life, but on the surface of Titan it is as hard as rock. The water ice there is like the silicon rocks on Earth that form the outer layers of the earth's crust.
The liquid filling the lakes and rivers of Titan is not water, but liquid methane, most likely mixed with other substances such as liquid ethane, which are present in a gaseous state on Earth. If there is life in the seas of Titan, it does not resemble our ideas about life. This will be a completely alien form of life for us, the organic molecules of which are dissolved not in water, but in liquid methane. Is this even possible in principle?
A team from Cornell University examined one key part of this thorny question by looking at the possibility of cell membranes existing in liquid methane. All living cells are essentially a system of self-sustaining chemical reactions enclosed in a membrane. Scientists believe that cell membranes appeared at the very beginning of the history of life on Earth, and their formation may have been the first step towards the origin of life.
Here on Earth, everyone knows about cell membranes from a school biology course. These membranes are made of large molecules called phospholipids. All phospholipid molecules have a head and a tail. The head is a phosphate group, where a phosphorus atom is bonded to several oxygen atoms. The tail consists of one or more strands of carbon atoms, 15–20 atoms long, to which hydrogen atoms are attached on each side. The head, due to the negative charge of the phosphate group, has an uneven distribution of electrical charge, which is why it is called polar. The tail, on the other hand, is electrically neutral.
Here on Earth, cell membranes consist of phospholipid molecules dissolved in water. Phospholipids are made up of carbon atoms (gray), plus they also contain hydrogen (sky blue), phosphorus (yellow), oxygen (red), and nitrogen (blue). Due to the positive charge imparted by the choline group, which contains a nitrogen atom, and the negative charge of the phosphate group, the phospholipid head is polar and attracts water molecules. Thus, it is hydrophilic. The hydrocarbon tail is electrically neutral, so it is hydrophobic. The structure of the cell membrane depends on the electrical properties of phospholipids and water. Phospholipid molecules form a double layer - the hydrophilic heads in contact with water are on the outside, and the hydrophobic tails face inward, connecting to each other.
These electrical properties of phospholipid molecules determine how they behave in aqueous solution. If we talk about the electrical properties of water, then its molecule is polar. The electrons in a water molecule are more attracted to the oxygen atom than to the two hydrogen atoms. Therefore, on the side of the two hydrogen atoms, the water molecule has a small positive charge, and on the side of the oxygen atom, it has a small negative charge. These polar properties of water cause it to be attracted to the polar head of the phospholipid molecule, which is hydrophilic, and at the same time repelled by the non-polar tails, which are hydrophobic.
When phospholipid molecules are dissolved in water, the combined electrical properties of both substances cause the phospholipid molecules to form a membrane. The membrane closes into a small sphere called a liposome. Phospholipid molecules form a bilayer two molecules thick. Polar hydrophilic molecules form the outer part of the membrane bilayer, which is in contact with water on the inner and outer surfaces of the membrane. The hydrophobic tails are connected to each other in the inner part of the membrane. Although the phospholipid molecules remain stationary relative to their layer, with their heads facing outward and tails facing inward, the layers can still move relative to each other, giving the membrane sufficient mobility that life requires.
Phospholipid bilayer membranes are the basis of all cell membranes on earth. Even the liposome itself can grow, reproduce itself and facilitate the occurrence of certain chemical reactions necessary for the existence of living organisms. This is why some biochemists believe that the formation of liposomes was the first step towards the emergence of life. In any case, the formation of cell membranes must have occurred at an early stage of the origin of life on Earth.
On the left is water, a polar solvent consisting of hydrogen (H) and oxygen (O) atoms. Oxygen attracts electrons more strongly than hydrogen, so the hydrogen side of the molecule has a positive net charge, and the oxygen side has a negative net charge. Delta (δ) denotes a partial charge, that is, less than a whole positive or negative charge. On the right is methane, the symmetrical arrangement of hydrogen atoms (H) around a central carbon atom (C) makes it a non-polar solvent.
If life exists on Titan in one form or another, be it a sea monster or (most likely) microbes, then they cannot do without cell membranes, like all life on Earth. Could phospholipid bilayer membranes form in liquid methane on Titan? The answer is no. Unlike water, the electrical charge of a methane molecule is distributed evenly. Methane does not have the polar properties of water, so it cannot attract the heads of phospholipid molecules. This ability is necessary for phospholipids to form the terrestrial cell membrane.
Experiments have been carried out in which phospholipids are dissolved in non-polar liquids at Earth's room temperature. Under such conditions, phospholipids form a “reverse” bilayer membrane. The polar heads of phospholipid molecules are connected to each other in the center, attracted by their charges. The non-polar tails form the outer surface of the "reverse" membrane in contact with the non-polar solvent.
On the left - phospholipids are dissolved in water, in a polar solvent. They form a bilayer membrane, with polar, hydrophilic heads facing water and hydrophobic tails facing each other. On the right - phospholipids are dissolved in a non-polar solvent at earthly room temperature, under such conditions they form an inverse membrane with the polar heads facing each other and the non-polar tails facing outwards towards the non-polar solvent.
Could living organisms on Titan have a reverse phospholipid membrane? The Cornell team concluded that such a membrane is not suitable for life for two reasons. First, at the cryogenic temperatures of liquid methane, the tails of the phospholipids become rigid, thereby depriving the formed reverse membrane of any mobility necessary for the existence of life. Second, two key constituents of phospholipids, phosphorus and oxygen, are likely absent from Titan's methane lakes. In their search for cell membranes that might exist on Titan, the Cornell team had to go beyond the familiar high school biology course.
Although phospholipid membranes have been ruled out, scientists believe that any cell membrane on Titan would still be similar to the reverse phospholipid membrane produced in the laboratory. Such a membrane will consist of polar molecules connected to each other due to the difference in charges dissolved in non-polar liquid methane. What kind of molecules could these be? For answers, the researchers turned to data obtained from Cassini and from laboratory experiments that reconstructed the chemical composition of Titan's atmosphere.
It is known that Titan's atmosphere has a very complex chemical composition. It mainly consists of nitrogen and methane in gaseous form. When the Cassini spacecraft analyzed the composition of the atmosphere using spectroscopy, it was discovered that the atmosphere contained traces of a wide variety of carbon, nitrogen and hydrogen compounds called nitriles and amines. The researchers simulated the chemistry of Titan's atmosphere in the laboratory by exposing a mixture of nitrogen and methane to energy sources that mimic Titan's sunlight. The result was a broth of organic molecules called tholins. They consist of compounds of hydrogen and carbon, that is, hydrocarbons, as well as nitriles and amines.
Researchers at Cornell University identified nitriles and amines as potential candidates for the formation of Titanian cell membranes. Both groups of molecules are polar, which allows them to combine, thereby forming a membrane in non-polar liquid methane due to the polarity of the nitrogen groups that make up these molecules. They concluded that suitable molecules would need to be much smaller than phospholipids so that they could form mobile membranes at temperatures where methane exists in the liquid phase. They looked at nitriles and amines containing chains of 3 to 6 carbon atoms. Groups containing nitrogen are called azo groups, so the team gave the Titanian liposome analogue the name "azotosome."
Synthesizing azotosomes for experimental purposes is expensive and difficult, since experiments must be carried out at cryogenic temperatures of liquid methane. However, since the proposed molecules had already been well studied in other studies, the Cornell team felt it was justified to turn to computational chemistry to determine whether the proposed molecules could form a mobile membrane in liquid methane. Computer models have already been successfully used to study the familiar cell membranes made of phospholipids.
It was found that acrylonitrile could be a possible basis for the formation of cell membranes in liquid methane on Titan. It is known to be present in Titan's atmosphere at a concentration of 10 ppm, plus it was synthesized in the laboratory while simulating the effects of energy sources on Titan's nitrogen-methane atmosphere. Because this small polar molecule is able to dissolve in liquid methane, it is a candidate compound that could form cell membranes under the alternative biochemistry conditions on Titan. Blue – carbon atoms, blue – nitrogen atoms, white – hydrogen atoms.
Polar acrylonitrile molecules line up in chains, head to tail, forming membranes in non-polar liquid methane. Blue – carbon atoms, blue – nitrogen atoms, white – hydrogen atoms.
Computer modeling carried out by our research team showed that some substances could be excluded because they would not form a membrane, would be too rigid, or would form solids. However, modeling has shown that some substances can form membranes with suitable properties. One of these substances was acrylonitrile, the presence of which in the atmosphere of Titan in a concentration of 10 ppm was discovered by Cassini. Despite the enormous temperature difference between cryogenic azotosomes and liposomes existing at room temperature, simulations demonstrated that they have remarkably similar properties of stability and response to mechanical stress. Thus, cell membranes suitable for living organisms can exist in liquid methane.
Computational chemistry modeling shows that acrylonitrile and several other small polar organic molecules containing nitrogen atoms can form "nitrosomes" in liquid methane. Azotosomes are small, sphere-shaped membranes resembling liposomes formed from phospholipids dissolved in water. Computer modeling shows that acrylonitrile-based azotosomes would be both stable and flexible at cryogenic temperatures in liquid methane, giving them the necessary properties to function as cell membranes for hypothetical Titanian living organisms or any other organisms on a planet with liquid methane on the surface . The azotosome in the image is 9 nanometers in size, which is roughly the size of a virus. Blue – carbon atoms, blue – nitrogen atoms, white – hydrogen atoms.
Scientists at Cornell University see the findings as a first step toward demonstrating that life in liquid methane is possible and developing methods for future space probes to detect such life on Titan. If life in liquid nitrogen is possible, then the conclusions that follow from this go far beyond the boundaries of Titan.
When searching for habitable conditions in our galaxy, astronomers typically look for exoplanets whose orbits fall within the star's habitable zone, which is defined by a narrow range of distances within which the temperature on the surface of an Earth-like planet will allow liquid water to exist. If life in liquid methane is possible, then the stars must also have a methane habitable zone - an area where methane on the surface of a planet or its satellite can be in the liquid phase, creating conditions for the existence of life. Thus, the number of habitable planets in our galaxy will increase sharply. Perhaps on some planets, methane life has evolved into complex forms that we can hardly imagine. Who knows, maybe some of them even look like sea monsters.