Civilizations and cultures have different New Years and different ways of celebrating. This year-round calendar has its own cultural value and recognition. Despite the variety of calendars, we humans measure time in hours, days, months, and years. And, in this calculation, we consider the 366th day to be a new year after 365 days have passed.

 All this is based on the astronomical calculations made by combining the movement of the sun and the rotation of the planetary constellations as seen from the earth. 

The famous American astronomer Carl Sagan, who believes that science should be spoken in a language that can be understood by the people, had a strange idea in his mind one day - what kind of time table would it be when trying to fit the time since the beginning of creation into one year of the human calendar? He started calculating on this. Tried to fit the development from its origin to the earth's 365-day time table. And, in the end, a crazy calculation came out.

He presented it in his book 'The Dragons of Eden: Speculations on the Evolution of Human Intelligence', which was published in 1977. This concept of Karl's became very popular. He mentioned it more clearly in his next book 'Cosmus (1980)' with more research. And made it more popular through the television series called 'Cosmus: A Personal Voyage'.

Carl Sagan's cosmic calendar is so amazing that seeing the age of the world through its eyes is an awe-inspiring feeling that subdues someone. According to recent studies, scientists estimate that the universe began 13.8 billion years ago. Sagan condenses such a long period into the human mind's grasp of a year. When the history of the entire universe is summed up in a calendar year, each day represents 3.78 million years, each hour represents 1.58 million years, each minute represents 26,000 years, and each second represents 438 years. 

In that way, when did the universe originate? Sagan's calculations from January to December according to the English calendar have been converted here into the Nepali calendar for convenience. According to that, the universe definitely started at midnight on the 1st of Baisakh. In the vast void of nowhere there was suddenly a huge explosion, the Big Bang.

Stephen Hawking wrote in his book 'A Brief History of Time' - The Big Bang informs the origin of the universe, which was the beginning of time and space. At that time the universe was confined to a very small, hot and dense point, like a newly conceived baby developing from a small lump of flesh in the womb. Within seconds it dissipated and formed quarks, electrons and other fundamental particles. By Baisakh 3, the first hydrogen and helium atoms were formed, making the universe transparent. 

The first stars were born in the second week of Baisakh ie around 10th. These were huge and short-lived. These stars undergo nuclear fusion at their cores, converting hydrogen into helium, carbon and oxygen. These stars were destroyed in supernova explosions. And the heavy elements that came out of them spread out into space, forming the basis for future stars, planets and life. Over the next month, gravity pulled the gas and dust together into massive structures. This was the birth of the galaxies. Our own galaxy, the Milky Way, was born around June 1.

At the beginning of November, a huge cloud of gas and dust, called the Solar Nebula, erupted, leading to the birth of the Solar System. Earth was born around this time but its initial state was full of meteorites, volcanic eruptions and cooling processes. 

One-celled organisms originate on November 15 on Earth, which has evolved into a warming, cooling planet. Due to these single-celled organisms like bacteria, the earth's atmosphere was gradually filled with oxygen. After this, multicellular organisms evolved by 5 p.m. From these multicellular organisms, aquatic and terrestrial animals evolved, and finally, giant-bodied dinosaurs were born on 15th December. He ruled the earth till 30th of Chait. At the end of the year, a huge meteorite destroyed their clan. 

People were born in the last hours of Chait 31. At 10:00 PM on Chait 31, the first hominids, similar to today's humans, evolved. Homo sapiens, the ancestor of modern humans, was born at 11:52 PM. All of human history—agriculture, cities, empires, science, and technology—happened within the last 30 seconds of the cosmic calendar. 

According to the cosmic calendar, the entire history of human civilization, from the beginning of agriculture to the present digital age, all happened from 11:59:30 to 12:00 on the night of Chait 31st. In this very short period of time we invented fire, built cities, had great philosophers, had the industrial revolution and were even able to travel into space.

At 11:59:30 p.m. on Chait 31, we invented fire. After learning to control fire, our ancestors were able to cook food, fend off wild animals, and protect themselves from winter. Fire helped humans stay active even at night, which encouraged the development of the brain. At 11 hours 59 minutes 40 seconds, man entered the agricultural age from the nomadic age. Now man learned to plant crops and raise animals. Then there was no need to depend on hunting for food. This marked the beginning of permanent settlements. 

Gradually division of labor started in the society. Farmers, craftsmen, priests and rulers emerged. Civilizations were born 5 seconds after that, i.e. at 11:59:45 p.m. The city lived in Mesopotamia. The civilizations of Egypt, the Indus Valley, and China developed writing, mathematics, and law. Buddha, Socrates and many other philosophers were born at 11:59:55 exactly five seconds before the end of the year. Three seconds later, the Industrial Revolution happened. Steam engines and factories were built. The production of

goods was revolutionized. Modern cities were built and a large economy emerged. Man made great leaps in science and technology. These two great world wars happened within a second. Environmental pollution, exploitation and social inequality also started. Within one second, man abandoned the wheelbarrow and invented the car, the airplane, the train, and the rocket. stepped on the moon. He tried to find out what is the secret of the world by breaking the atom.

In this way, the entire life span, achievements and development of man is not even a moment in the calendar of the universe. Globally, the average human life expectancy is now 73.16 years. This is 167 milliseconds according to the cosmic calendar. A millisecond is the amount of time a second is divided into a thousand times. In a millisecond a human cannot even blink an eye. Having said that, human lifespan is insufficient to form even a single color in this vast canvas of existence. 

The world is so vast and so fleeting are our lives and achievements. Oh, no, it's amazing! Carl Sagan used the cosmic calendar to explain this amazing truth and gave mesmerizing speeches.