15.Goutami Debnath
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I love breaking down complex issues in simple words
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Theory of Evolution
Is evolution merely a theory or a fact? Where were our ancestors from? Hello friends! Approximately 4 billion years ago, life began on Earth. After billions of years of evolution, numerous species of plants and animals evolved. All these trees, plants, animals and creatures that you see today, all of them exist due to evolution. One of these species is Homo Sapiens, that is, humans. But the question arises, if humans came from apes, then why do apes still exist? Why didn't all these monkeys, chimpanzees and gorillas evolve into humans? Such questions are often asked by people. Some people deny evolution. They say it's a lie. How true is this evolution theory? Is it merely a theory or a fact? And how did these different types of animals evolve? Let's find out in this article. Let's begin with clearing the biggest misconception. Evolution theory doesn't claim that monkeys became humans. Instead, it claims that all chimpanzees, gorillas, monkeys and humans have the same ancestor. And that ancestor is not alive today. If you want to visualize evolution, imagine a tree. A tree starts with just one stem. Then it grows branches. Then it grows smaller branches. If it keeps growing such, you see the tips of the tree. Those endpoints are all the living creatures that exist today. But one question that will still linger in your mind is, why did some of our ancestors evolve into humans and some into chimpanzees and some monkeys? Why? You will get the answer later in this article. In the year 1859, Charles Darwin wrote the historic book ‘On the Origin of Species’. In this book, he talked about the theory of natural selection. Now, when you hear the term ‘theory of natural selection’, you might feel that it is a mystical thing. There must be some complicated inner engineering in all living beings. But, no. It’s actually very simple. Whenever there is reproduction, whether it is in humans, animals, trees or plants, genes pass on from one generation to another. Our genes pass on to our children. But the genes pass on with certain mutations. There are slight changes in the genes. You can see some variations. And these variations are often inherited by future generations. For example, if you have brown eyes and your children have green eyes, it means that a mutation has occurred in their genes. The genes that decide the colour of the eyes mutated. It is possible that the next generation of their children will also have green eyes. Often, these variations are beneficial and harmful, depending on the environment. Some survive and some die out. This process is called natural selection. For example, let's say a frog, which is brown in colour, lives in a jungle. It has 5 children. 4 of the 5 are brown in colour and the one is green. The green frog can disguise itself well and can camouflage itself among the green trees. This gives it an advantage. One day, a predator comes and eats the brown frogs because they are easily visible. But this green frog is not spotted, it is safe and so its descendants are also green in colour. In a similar way, broadly speaking, the theory of natural selection works. Here, a term is used, ‘Survival Of The Fittest.’ Many motivational speakers misuse this term by saying that only physically fit people will be able to survive. People imagine that only those who have big biceps, triceps, and six-pack abs, will be able to survive according to the Theory Of Natural Selection. But this statement is wrong. Fit doesn't mean the biggest, the most powerful person. According to Charles Darwin, fit means the one who fits best in the environment around him. Here, the environment doesn't mean just the climate and temperature around you. It also includes the plants and animals around you. Who fits the situation the best? So, whether you are fit or not, can change with time. During the era of dinosaurs, due to natural selection, some evolved to be huge. Because a bigger size could easily protect them from their predators. But on the other hand, when there was a lack of food, being fit meant downsizing. So that the food requirement could be reduced as well. So, some evolved to be smaller in size. Similarly, some animals evolved to have more hair on their body so that they could get more insulation in the cold. Like polar bears. With their thick fur, it is easier to stay warm in cold weather. But on the other hand, some animals like humans evolved to have less body hair. So that it's easier to regulate their body temperature in summer. Now that you have understood the basics, let's understand how evolution happened. On the tree of evolution, if you go back in time you will find common ancestors with every species. Humans and monkeys have a common ancestor. Humans and cows and buffaloes have a common ancestor. All animals and trees and plants have a common ancestor. If we go back in time, it began approximately 4 billion years ago. The earth was vastly different at that time. There were no continents on Earth. Earth was covered with only water. And this water is where life began. What was the first organism? Scientists have given a very simple name to this first organism. They have called it the First Universal Common Ancestor. In short, it became FUCA. At that time, there were no genes, no DNA. There were just some free-floating nucleotides which assembled into an RNA. This RNA made a molecule called PTC and self-organised to form FUCA. The first ancestor for all of us was not even a cell. Today, we call cells the building blocks of life. But since FUCA was not even a cell, was it even a living thing? Was it living or non-living? It's difficult to imagine. But imagine a virus. A virus is neither called living nor non-living. A virus cannot grow or reproduce on its own unless it is in a host's body. Imagine something like this. I won't go into the technical details here because that would need a separate article. How, in the beginning, there were only a few elements which became nucleotides and then RNAs. If you want me to make a separate article on this, let me know in the comments. But for now, let's move ahead. 3.8 billion years ago, FUCA evolved into a unicellular organism. We call it LUCA, Last Universal Common Ancestor. All the living things on earth, trees, plants, animals, bacteria, and fungi, all of us have a common ancestor, LUCA. Scientists believe that it must have been a prokaryotic microbe with a cell membrane. You must've studied the difference between prokaryotes and eukaryotes in school. Eukaryotes have a proper nucleus in the cell. Whereas, Prokaryotes don't have a proper nucleus. Scientists have estimated that there were about 355 genes in LUCA. These 355 genes are found in every organism living on Earth to date. But this is a very new discovery. Scientists discovered this in July 2016. William Martin of the University of Dusseldorf made this discovery. Four months before this discovery, scientists created the smallest synthetic cell that can survive and reproduce on its own in a laboratory. There are 473 genes in the synthetic cell. But in LUCA, there were 355, fewer than in the synthetic cell. That's why LUCA is classified as half-alive. It wasn't properly living. Scientists believe that the viruses we see today, must have started evolving either before LUCA or the viruses must have started co-evolving with LUCA. Because from the very beginning, viruses have played a crucial role in evolution. Even though the COVID-19 virus was the black sheep of the virus family, but, for our survival today, everything needs some virus or other. With LUCA, we saw it reproducing through cell division. And evolution took place after millions of years when LUCA branched out into two. Bacteria and Archaea. These two microorganisms are very similar to each other. They differ slightly in terms of the cell wall and plasma membrane. Many billions of years later, a very special type of bacteria emerged due to evolution. Cyanobacteria. This was the first bacteria to be able to do photosynthesis. Using sunlight to generate energy. Water was used as fuel and the end product was oxygen. When a lot of cyanobacteria in the ocean used photosynthesis, a large amount of oxygen was released into the air. This event is called the Great Oxygenation Event. This led to high levels of oxygen in the atmosphere. This event took place 2.2 billion years ago. But evolution had to step in here to make the DNA stronger and more protected. This led to the formation of the nucleus in the cell. DNA was kept safe inside the cell so that it could be protected. Secondly, after millions of years, we can see evolution outside the nucleus, in the cytoplasm. Some types of cyanobacteria turn into chloroplasts. This is why all plants and trees are able to photosynthesise today. This was the birth of the plant kingdom. On the other hand, since there was an abundance of oxygen in the atmosphere, an ancient bacteria decided to use this available oxygen. To use oxygen to generate energy. This was the beginning of Aerobic Respiration. This bacteria evolved further inside another Archaea to form Mitochondria, which is now known as the powerhouse of a cell. An important element in all eukaryotes. Later on, these eukaryotes split into three sub-branches. The animal kingdom, fungi kingdom and algae kingdom. The Algae Kingdom is also called Protista. Here you can visualize the Tree of Life being born. Initially, there are three branches, bacteria, eukarya and archaea. And then eukarya branched out into plants, animals, fungi and algae. Scientists are still debating whether the Eukaryotes originated from Archaea or if Archaea and Eukaryotes are two separate branches with a common ancestor. By now you must be thinking about when will we get to monkeys evolving into humans. Here we are still talking about bacteria and microorganisms. Some people are ashamed that humans are related to monkeys and here we are talking about bacteria. *How insulting!* But this is the truth, friends. In each of our bodies. Only 43% of the cells in our body are human cells. The rest are bacteria, viruses, fungi, and RKI cells. If we go back to the story, about 900 million years ago multicellular life was born. Why? Because of evolution. It was easier to survive if the cells were in a group. Instead of being unicellular and alone, multicellular organisms had increased chances of survival. That is why we see multicellular organisms. About 555 million years ago, we see a common ancestor of all animals. The Ikaria Wariootia. It was smaller than a grain of rice. It was a bilateral worm which had a front and a back end. Bilateral refers to the symmetry. The organism would be vertically or horizontally symmetric. It means that all organisms would have a right side and a left side. And both sides are similar to each other. There are very few exceptions to this. Such as a starfish, that has radial symmetry instead of bilateral symmetry. In fact, all animals are bilateral. Be it a human, a pig, a spider or a butterfly. So, the scientists found these fossils in South Australia and when the fossils were carbon-dated, they were found to be from a creature that lived 555 million years ago. It was also a bilateral creature. It is considered to be the oldest organism ever discovered. This is why it is known as the ancestor of all animals. Then the vertebrates, or the spine, started to develop. All fishes, reptiles, birds and mammals are called vertebrates because they have a spine. The first spine was developed 480 million years ago. It was a fish called Arandaspis. After this, organisms started evolving to have four legs. The animals that have four legs are called tetrapods. And this development happened in water. We haven't come up on land in this story yet. 375 million years ago, this fish lived, which is called Eusthenopteron. It is a 6 feet long fish, with a very strong jaw and sharp teeth. It is said to be the connection between all the fish and land vertebrates. Perhaps one day, the fish said, fear is the way to victory, and it moved from water to the ground. I'm kidding, evolution does not work like that. Look at this animal. The Tiktaalik Roseae discovered in 2004. Its big fore fins were able to support it to be able to live on the ground. Realistically, this animal must have been living in a shallow ocean. Many times, due to climate changes, the ocean receded and it was forced to stay on land and it was able to survive there. Its skull was like a crocodile so it could bite and eat. But that doesn't mean that all the organisms moved from water to the ground. Evolution never has a linear progression. It doesn't move in one direction. Evolution can happen in all directions. This fish was a relative of this Tiktalik. Qikiqtania Wakei. It is believed that it came to the ground for a while, but couldn't adapt to the conditions, and went back to the sea. Similarly, some organisms came to the ground but went back to the sea to evolve. Some good examples of this are whales and dolphins. Whales and dolphins are mammals. They are more closely related to humans than fish. Unlike fish, they can't breathe underwater. They have to come up to the surface to breathe. This means that dolphins and humans must’ve had a common ancestor who lived on the ground. Some of the descendants of those ancestors stayed on the ground while some went back to the sea. If we move forward in the story, 368 million years ago, amphibians began evolving. Amphibians are animals like frogs and salamanders, which can live in water as well as on land. Then began the evolution of reptiles. Snakes, turtles, alligators, crocodiles, lizards. Dinosaurs later evolved from this branch. Dinosaurs started coming around 230 million years ago. And if you want to know the story of their evolution in detail, I discussed it in the article on dinosaurs. When did dinosaurs start evolving first and when did they die out? I will put the link to it in the description below in case you haven't seen the article. Moving forward, 225 million years ago, we see this 20 cm long animal that looks like a mouse. It is named Brasilodon Quadrangularis. It is now considered the oldest mammal in the world. It was discovered last year. Before this, scientists believed that the oldest mammal in the world was Morganucodon, which looked something like this. It existed 205 million years ago. The interesting thing is that it used to lay eggs. Mammals, as we all know, are such animals who are fed their mother's milk. Humans, monkeys, dogs, cats, tigers, lions, all these are mammals. Normally, mammals do not lay eggs. But exceptionally, the mammals that do lay eggs are called monotremes. Today, 5 species of monotremes are alive. One of them is the platypus. Platypus fossils have been found from as early as 120 million years ago. Those fossils were not much different from today's platypus. There were only a few changes. That is why platypus is considered one of the most primitive animals to be still alive. Apart from monotremes, there are two more branches in mammals. The placentals and the marsupials. Placental mammals are animals in which babies develop in the uterus of their mother, such as humans. But marsupials have a pouch for their babies to develop in, such as kangaroos and koalas. So basically, there are three different ways to nurture a child across these three branches of mammals. One is by laying eggs. The second is nurturing it in the womb. And the third is nurturing it in a pouch. They are all grouped together in the category of mammals because the babies drink their mother’s milk. Monotremes diverged from the rest of mammals 166 million years ago. Then, 125 million years ago, marsupials and placental mammals evolved in different directions. Till 40 million years ago, the continents of South America, Antarctica and Australia were connected. So when marsupials evolved, they spread over these 3 continents. At that time, there was no ice in Antarctica. Antarctica had a forest too. Today, when these continents have separated, we see marsupials only on these 3 continents. But most of the marsupials are found in Australia. In South America, they couldn't compete with the other mammals to fit in. But in Australia, they did not face competition from other mammals, that's why we see animals like kangaroos and koalas only in Australia. The oldest fossil of placental mammals was found in northeast China, dated to be from 125 million years ago. This animal's name is Eomaia. However, in a 2013 study, scientists countered this by saying that this animal did not have all the features that we see in the rest of the placental mammals today. Maureen O'Leary and her co-researchers countered this and said that the first placental mammal was actually found only 65 million years ago. And that animal looked like this. It looked even more like a rat. Now we are coming to the most interesting part of the timeline because, at this time, the dinosaurs had already been extinct. The asteroid had killed all the dinosaurs. But this meant that mammals had a chance to dominate. There were many empty spots in Earth's ecosystem where mammals could fit in. A study published in the Science Journal has shown that the boom in placental mammals began only after the dinosaurs went extinct. If this hadn't happened, we would never have seen diversity in placental mammals. Humans would never have existed. 40 million years ago, the Indian continental plate collided with Asia, which formed the Himalayan mountains. At the same time, placental mammals split into different branches. One such branch is that of the Ungulate, the mammals with hooves. Cows, buffaloes, pigs, goats, camels, deer, and hippopotamus, all belong to this category. This branch was later divided into even-toed and odd-toed ungulates. The animals with an even number of toes and the animals with an odd number of toes. Some of the odd-toed ungulates are donkeys, horses, zebras and rhinoceros. The rest of the examples were even-toed ungulates. Apart from these, another branch was formed of the Carnivora Order. Carnivorous placental mammals. Dogs, cats, lions, tigers, and hyenas all of them belong to this category. Interestingly, whales and dolphins are classified as Cetaceans and their closest ancestry is with Ungulates. You heard it right. It means that whales and dolphins are most closely related to cows and buffaloes. Then there was the category of Afrotheria. It includes elephants and this small animal called Hyrax. Evolution never ceases to surprise you. How can a big animal like an elephant and this small animal belong to the same category? How can they have the same ancestor? This is possible because evolution does not happen in a linear fashion. It happens in every direction wherever it can fit. What are the reasons behind evolution? There are 4 main reasons. These 4 reasons are known as the Four Forces Of Evolution. I have already told you about two of the four. One is the genetic mutation. The mistakes while replicating the DNA causes mutations in the genes by chance during reproduction. It can be due to external factors as well. Such as ultraviolet light causing your skin cells to mutate and you get skin cancer. The second is natural selection. The traits of the genes that naturally fit the ecosystem the best evolution continues from there. But what are the third and fourth reasons? Let's talk about them now. The third reason is the Genetic Drifts. Basically, think of it as a big explosion in the environment, which changes everything. A big destructive event. Let's say there is a specific species of animal which is found on a specific island. And a volcano erupts on that island. Everything is destroyed. That animal will also be destroyed. But if a subspecies of that animal was present on a nearby island, then after a volcanic disaster, that subspecies will get a chance to continue flourishing. And in the future, that subspecies will be found everywhere. This type of event is called the bottleneck effect type of Genetic Drift. This happened in America hundreds of years ago. North American Bison were found everywhere in America. But humans hunted it to extinction. But a subspecies of it, called Plains Bison, survived in a national park in America. When conservation programs were started to save it, the bison population regrew. The population was entirely made up of this subspecies. This became a bottleneck event, which led to genetic drift. And all the bison in America today belong to this subspecies of Plains Bison. These bison came from merely about 100 individual ancestors. The 100 bison that survived in Yellowstone National Park by chance. Another type of genetic drift can be the founder effect. When a small population of an animal gets isolated and then goes to a place and reproduces. A good example of this can be seen among humans too. The Amish people. Amish people are a small community living in America and Canada. Their population is around 250,000 people. Their ancestors came from Germany and Switzerland around 200 years ago. Interestingly, only around 200 people came to America and Canada. But this community was so conservative that they never married any outsiders. They kept intermarrying within themselves. The result of this is that for the population of these 250,000 Amish people, their ancestors were among those 200 emigrants. To racists, this might seem like an excellent thing. Them getting married within themselves. But according to Charles Darwin, reducing genetic diversity is not a good thing. One of his 200 original founders was a person with a recessive gene which causes the Ellis-van Creveld syndrome. It's a disease that makes your hands and feet smaller and you have more fingers. Since they kept intermarrying among themselves, this recessive gene kept being passed on. And due to evolution, today, this disease is found proportionately more among Amish people than in any other species globally. So, from the perspective of evolution, genetic diversity is always better. To see intermixing in different types of genes. Now, let's come to the fourth reason, which is gene flow. This is similar to genetic drift, but here a population migrates towards another and there’s mixing between the two. An example of this is the insecticide resistance gene found in African malaria mosquitoes. This resistance gene was found in some other species of mosquito. But when the population of that mosquito came and interacted with these African mosquitoes, they passed on this insecticide resistance. Here, you might be wondering about the timeline of evolution. How fast or slow is evolution? There is no concrete answer to this. It depends on the species. Evolution can take millions of years, as we saw in the case of mammals. But on the other hand, it can take a year or two. A good example of this is the coronavirus. We have seen so many mutations in the SARS-CoV-2 virus since the COVID-19 pandemic started. The Delta variant, the Omicron variant. What else was it if not evolution? That's why it's surprising that some people still don't believe in evolution. Evolution is not just a theory, it is a fact. When we use the word theory, it means a scientific theory. A scientific theory is made only when there is ample evidence. Albert Einstein's Theory Of Special Relativity, the Theory of the Big Bang, and the Theory Of Evolution. They are known as theories, but they are facts. In this article, you understand the irrefutable evidence proving evolution. But there is no evidence to counter this. To prove that evolution is not true. It is estimated that 97% of scientists believe that evolution is the truth. We have the explanations of what happened. It is a shame that there are some politicians in our government who don't believe in it and want to remove it from the school syllabus. After learning about such irrefutable evidence, no sensible person will call evolution wrong. And so we come to the last part of our story. The evolution of primates. Research from 2021 found that the ancestor of all primates must have been alive 65.9 million years ago co-existing with the dinosaurs. The evolution of primates was a big branch among mammals. It was only after this that we get to see gorillas, chimpanzees, monkeys and humans evolve. What happened next? When and how did actually humans evolve? Let’s discuss this in a future article. That deserves a separate article of its own. Finally, it bears mentioning, I am reminded of a dialogue from Shaunak Sen’s documentary, ‘All That Breathes’. In it, it was said that life is a relationship, we are a community of air. Whatever breaths should not be discriminated against. This quote may sound spiritual. But if you think about it from the perspective of evolutionary history, it is a scientific statement too. All the species that exist today, trees, plants, animals, all of them exist in an equilibrium. An equilibrium where everyone fits harmoniously. Every species has its place in the ecosystem. Whether it is a blood-sucking organism like a mosquito, a shark or even a scavenger like a hyena, everyone is important in this ecosystem
By 15.Goutami Debnath2 years ago in Education
Biggest Mystery in Aviation
8th March 2014. At 12:42 in the morning, Malaysian Airlines flight MH370, took off from Kuala Lumpur. This flight was headed to Beijing. There were 227 passengers on this flight, 10 flight attendants, and 2 pilots flying this plane. Captain Zaharie Ahmad Shah, 53 years old, one of the seniormost captains in Malaysian Airlines. Highly experienced. And First Officer Fariq Hamid, 27 years old, it was a training flight for him. After completing this training flight, he would have been fully certified to become a pilot. This flight flies in the correct direction for about 20 minutes. But at 01:08 in the morning, this flight crossed the Malaysian coastline and reached above the South China Sea. In the direction of Vietnam. Zaharie reported that the plane was at 35,000 feet. Everything was running normally. About 11 minutes later, the airplane entered the jurisdiction of the Vietnamese Air Traffic. That's why the Air Traffic Control of Kuala Lumpur, radios the airplane saying, "Malaysian 370, Contact Ho Chi Minh. 120.9. Goodnight." Captain Zaharie answered by saying, "Good night. MAS 370." Everything sounds normal. And it was normal till this point in time. But these words by Captain Zaharie, were the last words from this airplane. After this, there was no news from this flight. The Malaysian Airlines flight disappeared suddenly. And this became the biggest aviation mystery in the world. "Breaking news tonight, a Malaysian Airlines flight, MH 370, disappeared on route to Beijing." "Flight MH370 entered in the Southern Indian Ocean." Merely 30 seconds after entering the Vietnamese Airspace, this plane disappeared from the radar suddenly. It was 01:21 AM in the morning. The Air Traffic Control in Kuala Lumpur didn't notice this, and when they do, they think that the plane had flown out of the range of their radar, and had entered Vietnam's airspace. So there's nothing unusual. On the other hand, the Air Traffic Control in Vietnam, saw that the MH370 entered their airspace, but disappeared from their radar suddenly. They tried to communicate with the plane, but there was no response from the other side. After repeatedly trying for 18 minutes, Vietnamese controllers informed Kuala Lumpur, that MH 370 had disappeared suddenly. Generally, in such situations, Kuala Lumpur's Aeronautical Rescue Coordination Centre, should have been notified, within 1 hour, about the disappearance of the plane. But it was only after 4 hours had passed, that an emergency response began. It was 06:32 in the morning. This was the time by when the airplane should have landed in Beijing. But it did not land. A search operation was called immediately. Efforts began to find the plane. If you look at the map, the plane was flying from Malaysia to Beijing, Vietnam lies in the middle, as well as the South China Sea. So obviously, the search operation began in the South China Sea, to look for the plane. This search operation was an international effort. 34 ships and 28 aircraft from 7 different countries, try to look for this plane that morning. But there was no trace of the plane. About 4 days later, on 12th March, it was reported that though the plane had disappeared from the civilian radar, but a military radar had spotted the plane that night. And surprisingly, according to this military radar, this plane was last seen at 02:22 in the morning. 02:22 AM. But it wasn't located above the South China Sea. Rather, it was near the Andaman and Nicobar islands. Westward from Malaysia, above the Strait of Malacca. And according to the readings of this military radar, this plane was flying North in the direction of the Andaman and Nicobar islands. The other way from Beijing. This news left everyone shocked. Where did this plane go? Did it fly towards India's direction, and crash in the Himalayas or in Kazakhstan? Some more days later, a new piece of evidence was discovered. From satellite data. It was found that the plane was trying to automatically communicate with a satellite. It is actually quite common. The large airplanes like the Boeing 777 they try to establish communication with satellites often. To make their communication easier. It is the same as your phone trying to automatically connect to known WiFi. It's similar. But the problem was that when this plane communicated with the satellite, it merely tried to log in, trying to establish a connection. No data was transmitted about the location of the plane. The satellite was simply aware that this plane tried to communicate but nothing more about where the plane actually was. But some scientists and investigators thought to use this to approximate the location of the plane. They thought that when the satellite received the communication, the satellite would have moved its antenna towards the direction of the plane. So they took the angle of the antenna of the satellite, to measure it and make calculations upon it, estimated the location of the plane. As I said earlier, the exact location couldn't be determined with the help of the satellite, but it could be used to estimate that this circle that you see in white colour, the plane could be anywhere within this circle. When it tried to communicate with the satellite. The plane tried to establish communication with the satellite 7 times. That's why you can see 7 different circles in white colour. These are known as Satellite Handshakes. Every circle shows the time when the plane tried to communicate with the satellite. The last circle here, the 7th circle, shows the latest time when the plane tried to communicate with the satellite. The last point where this airplane could have been. And it was really surprising because this circle was huge! It covers a lot of areas. From Kazakhstan, China, Indonesia to Australia, and covering a vast ocean, the plane could be anywhere in the last circle. Or perhaps further than this. This was the last point it tried to communicate. After this, the investigators did more calculations. With the speed of the plane. The remaining fuel in the plane, and then estimated that the plane could be in this shaded area of the circle. On this arc of the circle. It was famously called the 7th Arc. This 7th Arc is 2,000 km west of Australia, and occupies a large expanse of area. It was in such a part of the ocean that hasn't been explored much. On this map, you can see the location of the satellite that was used for the prediction. The outermost yellow dotted circle that you see, is the range till which the plane could travel with its fuel. With the flight time of 7 hours. And the curved arc in red that you can see, is the 7th Arc, the place where the plane is assumed to have crashed. After this, several search operations were called, The yellow shaded regions show you the places where the search operations were conducted. And the orange area, is the priority search area, where the most number of search operations were conducted. By April 2014, the search operations on the surface of the ocean were stopped. Because it wasn't fruitful. Since the plane had crashed, it would've sunk into the ocean. It wouldn't be floating on the ocean's surface. And so deep ocean searches were being conducted. At this point in time, this was the largest and the most expensive search operation conducted. For weeks, months and even years, they tried to look for the plane but didn't find anything. 3 years later, And after spending $160 million, they called off this operation. And this operation was deemed a failure. But there was one piece of good news amidst all of this, in July 2015, the first piece of debris was found from this plane. The debris reached the Island of Réunion by floating. This island is in the East of Madagascar. The flaperon of the plane was found here. You can see it in the photo, it is a broken part from the plane. After this, in 2018, an American company Ocean Infinity signed a new contract with the Malaysian government. They wanted to conduct the search operations and if they aren't able to find the plane, they wouldn't charge any fees. No find, no fee. On this condition, they began a new search operation. They have highly advanced underwater surveillance vehicles. While conducting this search operation, they were mapping the ocean floor. And in this search operation, they found in the area of the 7th Arc, that there are several underwater volcanoes, several cliffs and mountains as well. They kept searching for months. But unfortunately, they failed in their mission too. They decided to run background checks on the passengers of the plane. And a background check on the pilots of the plane to look for their history. And whether someone tried to hijack the plane. After these investigations, some theories came forward. About what could have happened to the plane exactly. Come, let's look at the theories and assumptions one by one. First, they started with how could the plane disappear from the radar. Either there'd be any electrical failure in the plane. Or there'd be an accident, Or there might be some technical failure in the plane, because of which, the equipment stopped working. Or perhaps any passenger or pilot switched off the transponder manually. Doing this intentionally. In the first theory, Captain Zaharie Shah is being accused. It is being said that the captain intentionally disabled communication and took the plane and crashed it into the ocean. But what could be the reason for him to do this? Some people say that he may have not been in the right mental state. Some people believe he was suicidal. Some people claim that this was a result of hijacking, like a terror attack. But why is Zaharie Shah actually being blamed here? There are some arguments that support this theory. The first point is that, the airplane turned nearly 180° from Vietnam back to Malaysia, autopilot couldn't have done this on its own. The airplane's pilot must have done this manually and intentionally. The second point is that, the airplane was flown directly above the border between Thailand and Malaysia. It is said that it was deliberately done. It was done intentionally. So that they could escape the airspace radar of both countries. The third point is really interesting, it is said that Zaharie Shah had a flight simulator at his home which isn't very unusual on its own, but on that flight simulator, he had mapped out a path, while playing a game, The path, coincidently, was near the same path, that MH370 actually flew. Hearing this, you may think this must've been the case. But the official in charge of this search operation completely denied this theory. He said that this couldn't have happened because there are many counter-arguments too. First, he was a highly experienced and seasoned pilot. He was respected by all. He had no family problems, no economic problems, he didn't have any past behaviour to suggest this, so there is no reason to doubt his integrity. If a pilot wanted to commit suicide, to crash the plane, there would be some sign in his behaviour or in his life. But nothing as such was found. That's why the second theory that is afloat, is that there must be some hijackers on the plane, some terrorists. They must have done this. When this second theory came forward, 2 passengers of the plane were under suspicion. They were Iranian, and they were suspicious because they were travelling with fake passports. One of them had the passport stolen from an Italian man. And the other had the stolen passport of an Austrian man. Both passports were stolen in Thailand. It is said that these men wanted to use the stolen passports to go to Europe and settle there. First, they had taken a flight to Beijing, and then they were supposed to take a flight from Beijing to Europe. Investigations revealed that the mother of one of these guys was present in Hamburg, Germany. Waiting for her son. But in the end, this theory of terror was rejected, because other than these stolen passports, there was no proof that they were actually terrorists intending to carry out a terror attack. They simply wanted to go to Europe and settle there. Using the stolen passports. In fact, Interpol confirmed this, saying that they were probably not terrorists. That's why we come to our third theory. It is said to be the most probable. It is said that the passengers and the crew on MH370, fainted because of oxygen deficiency. Including pilot Captain Zaharie Ahmad Shah and his co-pilot. They were unconscious too. The entire plane actually passed out. And kept running on autopilot. And there must have been some technical malfunctions on autopilot too, but basically, the autopilot kept running till the fuel of the plane ran out. And then the plane crashed into the ocean. Now, how could this oxygen deficiency have happened? There are several theories for it. Some people claim that there may have been a fire in the cockpit, electrical fire. Due to this, many systems may have stopped working, including the transponder. Some people believe that there may have been an accident due to which there was a sudden shortage of oxygen. Some people blame hijackers here as well. That some hijackers may have tried to create an oxygen deficiency. Let's take a possible example to see what might have happened. If I have to cite a typical example of this theory, it is said that this plane as soon as it entered the Vietnamese airspace, the pilots noticed some malfunctions, some wrong with the plane. So the pilot turned the plane 180°, to take the plane back to Malaysia. But when the plane started flying towards Malaysia, a terrible accident may have occurred, which led to oxygen deficiency, and everyone present in the plane fainted. Because of oxygen deficiency. Several systems stopped working and then the plane kept flying on autopilot. The military radar spotted the plane after this. And the autopilot turned Southwards suddenly, and it kept flying Southwards above the Indian Ocean, and crashed into the ocean 2,000 km West of Australia. Initially, there were many more theories about the plane. such as it was abducted by aliens. Or that the US military may have shot down the plane and it was trying to hide the fact. Or that Russian President Putin knows the location of the plane. Or that a new Bermuda Triangle may have formed at the place. There were many such theories. But obviously, they are not very likely. Many years have passed since this incident. And now in 2022, friends, finally, there's proof to tell us where this plane may actually be. Friends, this news is from 1 month ago. Richard Godfrey, a retired aerospace engineer, claims that he had found out the secret of this mystery. He did his calculations using some radio wave technologies. "Richard Godfrey combined data from British Inmarsat Satellite, figures from Boeing, Australian oceanographers, and new WSPRnet, amateur radio wave technology." "I have been tracking back, through the data, and out of that tracking MH370, I'm sure they will be able to find the aircraft." To explain this technology would be too detailed for this article, it is a complex technology. But it isn't a very new technology. Basically, he used the reflections of radio waves, to predict the path of the airplane. It is a technology that can catch the reflections of radio waves. Once a radio wave is emitted from a source, it gets reflected by the atmosphere, and weak radio waves reach some other place. And if a plane is flying from the path of the radio wave, you can say that it can be noticed. He built a computer program that can recognise the flight paths of airplanes through the weak signals. And according to his calculations, today, the MH370, actually lies on top of the 7th Arc. It is exactly on this point of the 7th Arc, in his opinion. And is 4 km underwater. Under the ocean, as I said, there are many cliffs and underwater volcanoes. You'd say that this area was already searched. True. In the most expensive search operation conducted by Australia, this area was already searched. But it is possible that they missed it somehow. Although the second search operation that was conducted, by the Ocean Infinity, they hadn't searched this point. Their instruments were more detailed. But Richard trusts his calculations so much that he has pinpointed the exact location with an accuracy of 40 Nautical Miles. Of the location of the plane under the sea. He has proposed that a new search operation should be conducted within a radius of 40 Nautical Miles and they would find it. This would be a very small area compared to the previous search operations. They would have to thoroughly look here. This is good news for the mystery of this flight. There may actually be a solution here. Although, some people do criticise Richard's methodology, that the methods he used to determine the location of the plane is not accurate enough. That the plane wouldn't be found here. But Richard believes that if the operation is started now, it would take only 1 year, and by the end of 2022, we would be able to see whether the plane is here or not. In Richard's opinion, the plane would be found here, obviously. A Drift Analysis was also conducted, looking at the ocean current. So that if the plane had indeed crashed in that area, the location of the various pieces of the plane, that would've flowed with the ocean current to reach various places. And according to this drift analysis, some pieces would have reached Madagascar and the islands around it, and those have indeed been recovered. Till date, 27 pieces of the plane have already been found. On several islands across the world. This drift analysis fits properly with Richard's analysis too. So perhaps, in the near future, we may get to uncover the mystery about what might have happened. But I hope that you found this article informative.
By 15.Goutami Debnath2 years ago in Education
Time Traveler from Year 2256
In March 2003, the FBI arrested 44-year-old Andrew Carlssin. Newspapers reported that this man was extraordinarily lucky. In the history of Stock Markets, he had earned like no other. He invested $800 and within 2 weeks, it turned into $350 million. The FBI suspected that he was running a scam. That he was an insider trader. When Andrew was questioned, he answered that he was a time traveller. He claimed that he was a traveller from 250 years in the future. And that he knew how the stocks would perform so he invested in them. And got the extraordinary result. The FBI was surprised at this. The FBI was convinced that he was lying. And they took it upon themselves to prove that he was lying. When they investigated some more, they found that Before December 2002, there was no record of Carlssin. Even more surprising was that on 3rd April, Carlssin had to appear in court for his bail hearing, but he had disappeared, never to be found again. Was he really a time traveller? Is it really possible to travel through time? Or is it only fiction for novels and films? In today's story, let's understand the concept of time travelling scientifically. "Great, are you talking about a time machine?" "You know the rules of time jumps, right?" "Time travel: a concept that has been explored since the early 1900s." "I have no idea, but when we're talking about time travel here. Either it's all a joke or none of it is." In 1895, writer H.G. Wells wrote his groundbreaking novel The Time Machine. It was after this that the phrase 'time machine' became popular. A machine that can take you into the future as well as the past. With it, you can travel through time. Although this novel was fiction, a science fiction novel, but several philosophers and physicists were inspired by it. Not only were serious research papers written on time travel, but many films were also made. If we think about it, the exact way time travel takes place can be used to classify it into different types. First, let's use sci-fi films, to understand this concept better. Time travel can be of many different kinds. The first is the one-way travel to the future. You travel to the future and you can't return. It is one-sided time travel. Interstellar is an example of this. In it, a time traveller travelled to the future, but his family members and other people keep on ageing, when he meets them again. Some had even died. The second way is Instantaneous Time Jumping. A person can jump from one point in time to another instantly using a time machine. It was shown in the film Back to the Future. And in The Girl Who Leapt Through Time. The third way can be when the time traveller stands still, and it is time that is moving around the traveller. This was shown in the film Harry Potter: Prisoners of Azkaban. When Hermione uses the time turner. The fourth is Slow Time Travel. As shown in the 2004 film Primer. The time traveller gets inside a box, with every minute he spends in the box, he goes back into the time by a minute. So if he wanted to go back a day, he had to remain in the box for a day. The fifth is travelling at the speed of light to travel through time. This was shown in Superman (1979). In it, Superman flew faster than the speed of light, and travels back in time. The question is, among all these concepts of time travel, which way is actually possible today? In real life. Which way may be possible in the future? And which way is completely unscientific and will never be possible. Don't be surprised, you might think that all of these are rubbish, science fiction, and can't be possible. That's not true. Some of these are actually possible to do, even today. Broadly speaking, there can be two types of time travel. One is to travel into the future, and the other is to go back into the past. Let's talk about travelling to the future first. The scientific explanations and theories of travelling to the future, are derived from Albert Einstein's Theory of Special Relativity. The concept of time dilation, was introduced by Einstein. Before Einstein, it was believed that time is constant. Whether you're on Earth, or on Mars or near a black hole. Time was believed to be something that was constant. One of the most famous mathematicians and physicists in the world, Isaac Newton was the one to say this. In his opinion, regardless of the speed with which you're travelling through space, regardless of the position, the flow of time would be constant. Albert Einstein was the first person to refute this. He said that Newton was wrong. Time isn't constant. He claimed that time was like a river. Like water flows in a river, sometimes it slows down, sometimes the flow of the river speeds up, similarly, the flow of time, sometimes it slows down and sometimes it picks up the pace. Depending upon speed and gravity. Yup, you heard it right, Einstein had said that time can actually be sped up and slowed down if the speed and gravitational force could be changed. This is known as time dilation. The way that your pupils dilate, similarly, time dilates too when the speed of the object increases or if an object is subjected to an increased gravitational force. How had Einstein actually discovered thisit's a long explanation. It took me days to understand that. So I won't go into that explanation. Basically, time dilation can be done in two ways. The first is with speed. If you are sitting in an object that is going very fast. Like an aeroplane or a spacecraft. The faster something goes, the more would time slow down for it. Relative to a person who isn't going as fast. If I have to explain it with a practical example, suppose you have two clocks, I keep one clock with me and put it on the ground. And I send the other clock with you on an aeroplane. The aeroplane goes around the earth once and lands back. If we then compare the two clocks, though the clocks showed the same time initially, but now the clock that you took with you on the aeroplane, the time it shows would be some nanoseconds behind the other. The two clocks wouldn't show the same time. Because one clock was travelling at a higher speed. It's subjected to Kinematic Time Dilation. I'm not making this up. There was an experiment in 1971. Atomic clocks were used. Because time was to be measured precisely. And it was seen that the clock that was in the aeroplane, the time it showed was behind that of the other clock. This was known as the Hafele Keating Experiment. This had proved Einstein's theory of time dilation. It doesn't mean that time is actually slowing down for the clock, the one on the aeroplane. Rather, it means that time is relative. If we observe the clock on the aeroplane from the ground, time slows down in our relation. Because we're seeing it, time is slowing down. For a person on the aeroplane, and the clock on the aeroplane, for it, time would continue to move as it did. Theoretically speaking, if we could build a rocket, that travels at the speed of light, and you get in that rocket. You remain in that rocket for 10 years travelling at that speed. And then you return to Earth, the time that you see on earth, would be 9,000 years later. Simply speaking, If you want to travel into the future, you can already do it now, It is scientifically possible to do so today. The only problem is that there isn't an aircraft that travels at this speed. You can get to the speed of light. But with improvements in technology, we can build more such aircraft and spaceships that can fly faster. It would slowly become possible. For now, Gennady Padalka, a Russian astronaut, is credited with the most time travel into the future. It's because he remained in space the longest. 879 days. And he was travelling at the speed of 28,000km/hr in space. Accordingly, he has travelled 0.02 seconds into the future. In comparison to the people on Earth, he is 0.02 seconds younger. with which we can travel so fast that we can travel through time significantly in the future, don't be upset. Because there's another way of Time Dilation as laid down by Einstein. By using gravitational force. Similar to time dilation with speed, gravitational force leads to time dilation too. More the gravity, more would be the time dilation. The time dilation that takes place because of gravity, to visualise it, Einstein asked us to imagine a fabric of space-time. Imagine a mesh, like shown in this photo, And put balls on it. You can think of these balls as planetary objects. The heavier a ball would be, the more this mesh would get wrapped. The more mass in the ball, in the planetary object, the more would be its gravitational force. Earth's gravitational force is less than Jupiter's. Sun's gravitational force is more than Jupiter's. Similarly, in the fabric of space-time, you get to see a curve, with the gravitational force of an object. The closer you get to an object with a high gravitational force, the more would you feel time slow down. Time would slow down for you. In this mess, you can see, the steeper the drop is, the more time slows down for you. You can have an approximate estimate with this visualisation. This basically means that if you want to travel through time in the future, spends some time near Jupiter, or around the Sun, or near an object that has even more gravitational force. Like a black hole. If you spend some time near a black hole, time would pass you by slowly. This is the same concept shown in the film Interstellar if you remember. The main character in it, lands on a planet near a black hole, and each hour he spends there, it's 7 years for the people not on the planet. That was the amount of time dilation in that film because of the black hole. It is a scientifically accurate depiction. It will actually happen like so. But whether someone can survive being that close to a black hole is unknown. It's said that black holes are the heaviest objects in the universe. It's also said that light starts bending around black holes. This was considered to be purely theoretical, but 3 years ago, a telescope clicked the first picture of a black hole and proved it. On 10th April 2019, the Event Horizon telescope clicked this picture. This photo went viral on the internet. Because this is the first rendered visual image of a black hole. Anyway, if we get back to time travel, I told you two ways of travelling into the future. The first is to travel at a high speed, and the second is to get very close to a gravitational object with a high gravity, and a high mass. Practically speaking, I would like to give you another example of this, the GPS satellites, that keep revolving around the earth, at a high speed, they are farther than earth's gravity than compared to us. That's why we get to see time dilation, in both senses, in the GPS satellites. And the scientists need to keep rectifying the time calculations on those satellites because of this time dilation. If they don't rectify the clocks on the satellites, then the time on those clocks and those on earth will differ. There would be problems with GPS communication. Interestingly, friends, there is a third way of time travelling in the future. Cryosleep. It has been shown in many films too. There was a recent film Passenger, you might remember. People were travelling on a spacecraft, they were frozen. They were in cryosleep, in it, for months and years, humans are put into a condition where they don't age. They remain asleep. It's science fiction. But in reality, NASA is trying to develop a Stasis Chamber. In it, astronauts would be kept in a state of mild hypothermia, in a cold environment, in it, astronauts would be able to sleep continuously for 2 weeks. A hibernation of sorts. The concept behind it is that when a body is kept cool, the chemical reactions in the body would slow down to quite an extent. this would lead to energy conservation in the body and would slow down ageing. There was a case in Japan, related to this, an injured man survived 24 hours without food or water, when his body went into a hibernation of sorts. The temperature of that man's body was only 22°C. Normally, if a human body is this cold for a long time, it may lead to death. But by chance, I don't know with what miracle, not only did this man survive, but he also made a full recovery from that mode. After his body was discovered by someone else. Medical reports claimed that there was no permanent damage to his body. His organs had slowed down and his brain was unharmed too. Cryosleep is something which may be developed in the future. By NASA or some other space agency. We'll have to wait and watch. But you would have noticed one thing. All the ways I talked about till now, were of time travel into the future. What about the past? Can we travel into the past, realistically? I sort of told you one of the ways to do it, the James Webb telescope. As of now, we can't travel into the past, But we can get a glimpse of the past. Because it takes a significant time for light to travel, from one place to another, even with how fast light travels, if we talk about distance in light-years, it takes years for light to travel to some places. So if we could get somewhere before the light reaches there, and then look back at the approaching light, the light would be from the past. That is how we can see the past. I explained it in detail in that artical, you can understand. This was getting a glimpse of the past. Can we actually travel through time into the past? On 28th June 2009, world-famous physicist, Stephen Hawking, hosted a party at the University of Cambridge. There were balloons and champagne at the party, but what was special about the party was that though everyone was invited, no one attended. Stephen Hawking had hosted this party for time travellers. If a time traveller was visiting our timeline from the future, they were welcome at this party. This comedic experiment was conducted to prove that it isn't possible to travel to the past. Had this been possible, we would see future time travellers all around us. Where are the travellers travelling to the past? Why don't we meet them? Theoretically speaking, Einstein's theory of relativity, doesn't disprove time travel to the past. Einstein had said that in the mesh of space-time, if a gravitational force is put on it that is so heavy that the object falls through the mesh, it would create a wormhole. We can use that wormhole to travel into the past. It's said that to do this, we'd need an extremely powerful gravitational field. Similar to the one of a black hole. Perhaps a spinning black hole can generate so much gravitational field, that it bends the curvature of the space-time back on itself. It would create a close time-like curve known as CTC. You can try to understand it through this diagram. You can try to imagine it. Nobel Prize-winning physicist, Kip Thorne believes that small wormholes get created and then disappear in space all the time. But they are really small. Smaller than atoms. And if we want to travel through them, we would need to open them up somehow. It would take a lot of energy to expand them. Not only normal energy, but we would need negative energy also. Negative energy is a kind of anti-gravitational energy that would repel the fabric of space-time. Like the same poles of magnets repel one another. Negative energy would work in the same way to repel it. This would make it possible to keep the wormhole for a long while, and to travel through it. How would this negative energy be harvested? How would it be created? It's something to think about. This is purely theoretical for now. But it is a theory by a Nobel Prize-winning scientist, so it holds a lot of weight. With this, you may think that it might be theoretically possible to travel to the past. But when we talk about travelling to the past, there are a lot of hurdles. There are major obstacles for us. I'm talking about Paradoxes. Such as the Grandfather Paradox. The paradox goes like this. Suppose I go to the past while time travelling. And I kill my great-grandfather. If he dies, how would I be born? If my great-grandfather died, I shouldn't be alive. And if I was never born, I never existed, how could I have gone to the past and killed him? How do you explain this? This is a paradox. Either I'm alive or I'm not. This goes against logic. There are some theories to explain this. Such as the Theory of Multiverse. The theory claims that what happened once was in one universe. But when you travel back in time and change something, it would create a new universe, creating a multiverse. So there are multiple universes with different things happening. Related to this, there's another paradox, the Predestination Paradox. It claims that when I'd go into the past, and do whatever, everything I do shapes my present timeline. This paradox claims that things are destined to turn out in a certain way. Things will play out as written in destiny. No matter how much you try to change the past, whatever you try to change, and the result of that change, would be your present. If you're confused, let me give an example. Suppose your friend meets with an accident, and he dies. I hope it doesn't but imagine that it happens, and you have a time machine. You go into the past, and try to prevent that accident from happening. But what actually happens? By going into the past, you have done something, that actually caused the accident. And then you find out that it was because you went into the past, and you tried to prevent that accident, that was the reason for the accident. This was the concept in many films. 12 Monkeys, Timecrimes (2007), The Time Traveller's Wife (2009), Predestination (2014). Overall, there would be many logical problems when travelling to the past. There would be paradoxes, due to these, it may never be possible. But travelling to the future, it is possible, even today. And it will become more and more probable in the future. And to get a glimpse of the past, is currently possible too. So in a sense, time travel already exists. And as shown in films like interstellar, it was the scientific truth to an extent. But what about Andrew Carlssin's story? I didn't say much about it. The story that I told you at the beginning of the story, friends, was actually a story published in a satirical newspaper, called The Weekly World News. Later it was printed by Yahoo News, and several other media organisations reported the story, as if it were fact. But the truth remains, that story was a satire. It was fake news that was circulated in newspapers, and people believed that it was true. It was a fabricated story basically. I hope you found this informative.
By 15.Goutami Debnath2 years ago in Education
