chain laws of nature
The chain rule is called the chain rule in English, and is a term that appears frequently to explain the causal relationship of various social problems. The chain rule applies to all natural phenomena without exception. The same is true in the huge space-time world of the universe. The universe started with the Big Bang 13.8 billion years ago, and within the first 380,000 years hydrogen, helium, and some lithium were formed. These are the simplest basic elements with atomic numbers 1 to 3. Hydrogen molecules formed by the fusion of two hydrogen atoms currently have about 20 billion times the mass of the Sun in the gaseous state in our galaxy alone. In an interstellar molecular cloud composed mainly of hydrogen molecules, protostars were formed by agglomeration due to external pressure and self-gravity. Most are made collectively, and rarely one by one.
About 200 billion stars in the Milky Way are all, without a single exception, born from molecular hydrogen clouds. Among them, from the core of large stars to iron with atomic number 26 through the nuclear fusion process, and the moment the large star explodes into a supernova when its life is over, or the moment when neutron stars collide and explode, from uranium with atomic numbers 27 to 92 was made Of course, gold with atomic number 79, mercury with atomic number 80, and radon with atomic number 86 were created in that way. Large stars have a much shorter life span of about 10 million years than small stars (average lifespan of more than 10 billion years), and these various elements are scattered throughout the universe. Small stars have a very limited role in forming heavy elements because this fusion process is so slow.
The production process of various elements in the core of a large star has continued for more than 9.2 billion years from the birth of the universe to the birth of the solar system, and has produced many kinds of elements by repeating birth and death at least 1,000 times. These various elements mixed in the interstellar gas coalesced into dust and rocks. About 4.54 billion years ago (or 4.6 billion years ago), an unknown supernova exploded and compressed the interstellar gas that had gathered around it, and finally the solar system was born. They gathered and grew into numerous asteroids and planets. One of them is our planet Earth. All the processes in the solar system were chained by the very unknown supernova.
early birth of the earth
At the time of its birth, the earth was in a molten state where everything was melted, and heavy metals such as iron and nickel gathered at the center of the earth, and as time passed, the surface gradually cooled and crust and rocks were formed. The ice water delivered by comets from the edge of the solar system is added to create the sea and as water circulates, it governs the Earth’s climate along with the atmosphere of the Early Eocene, where most harmful gases and little oxygen were present. Meanwhile, the molten iron in the outer core of the Earth’s center creates a strong magnetic field to block various harmful cosmic rays from the sun and space. Iron is not only a useful metal in our daily life, but it also creates a protective film that protects our lives.
In the early days of birth, the earth had only rocks and no land or soil. At the moment when the sun’s activity weakens and the solar energy decreases, the ice age begins on Earth, where rocks and seas freeze and thaw again and again, and rock debris and soil started to form due to strong tidal action that occurs as the moon approaches. 3.7 billion years ago, photosynthetic cyanobacteria, represented by stromatolites, were born, and oxygen began to gradually increase in the atmosphere. The Cambrian Explosion occurred about 540 million years ago when photosynthesis took in carbon dioxide and produced oxygen, the air of life, and the atmosphere was quite rich in oxygen. In the beginning, life was created in the sea, and as they gradually evolved, various kinds of life abounded in the sea.
Asteroid impact and the feast of life
Until about 400 million years ago, animals could hardly live on the ground because the moon was close and the tides were large, so there were few opportunities for sea animals to come up to the ground, and the ozone layer that blocks UV rays was not formed because there was not enough oxygen in the atmosphere. It was not suitable for animals to live on land. As the moon gradually receded, the difference between tidal and tidal waves became gentler, and an ozone layer formed in the upper atmosphere, allowing animals to live on land, and finally, the feast of life overflowed in the sea, land, and air. The period of prosperous megafauna is the Cretaceous and Jurassic, and dinosaurs were born about 220 million years ago and suddenly went extinct 65 million years ago. Dinosaurs lived as top predators for 150 million years, and 50% of all populations, including 100% of these giant animals, became extinct in a single blow from an asteroid with a diameter of about 10 km.
The fall of an asteroid to Earth is inevitable. The Earth was created because these asteroids were made by merging together. Of course, it is still falling day by day. In the form of meteor showers, or shooting stars, it is falling by hundreds of tons per day every day. Fortunately in this day and age, they are mostly small things, and the large ones are very rare. On the morning of June 30, 1908, a huge comet meteorite collided with Tunguska, Russia, and exploded in the atmosphere, devastating an area about three times that of Seoul. A few years ago, a fairly large thing fell on both pearls and Russia and became a topic of discussion. What would have happened if an asteroid hadn’t deviated and collided with Earth 65 million years ago? Dinosaurs may have survived longer and continue to dominate the Earth. If small animals, including apes, were born and lived together in the future, they would become prey for the dinosaurs, or the apes might not have been born at all. Even if they were born, it would have been difficult to evolve into modern humans.
From the point of view of small animals, the collision caused by an asteroid can only be a very grateful event. However, since the ice age came several times later, the megafauna could not tolerate the cold and eventually went extinct. Just as the giant asteroid impact is grateful, the Ice Age is a process that mankind is grateful for. The greatest winner of this ice age is the great apes, the ancestors of mankind. Perhaps the role of the brain has gradually developed because it has struggled to survive the cold and adapt. If you look at the confessional complaints of Philoctetes, a hero in Greek mythology, extreme human suffering sometimes makes us mature. – ‘If it had not been for the wounds of snake bites, the misfortune of being abandoned by my colleagues, and the desperate loneliness I had to experience on this island, I would not have thoughtless and worried like an animal. I became a human only when pain took hold of my soul and plunged me into deep anguish’. Just as those among us who have overcome various difficulties wisely will eventually succeed in life, mankind inevitably has gone through such a process. The planet Earth, which looks lonely but beautiful from space, has miraculously turned into a living planet after so many hardships, and we humans have become victorious animals.
The universe, which started from the simplest element, hydrogen, creates various elements from the nucleus of a big star through magical fusion alchemy, and later becomes the basis of the Earth’s planet and all living things. And I can’t help but feel awe. The fact that we live together on planet Earth, the only home in the universe, is a miracle in itself, and we should be infinitely grateful for this. I hope that we can all live in harmony with nature and respect each other.
Young-woong Lee, Emeritus Researcher, Korea Astronomy and Space Science Institute
※ Contributions by external writers may differ from the editorial direction of this paper.