Around this time a few years ago, a close friend of mine passed away after suffering from acute liver cancer for a couple of months. He was fine when I saw him in September, but he suddenly developed an illness and his condition worsened day by day until he finally passed away a day before the New Year.
That’s how I spent the New Year at my friend’s funeral. On one wall of the funeral home, two poems by Tang Dynasty poet Baek Ju-yi were posted in large letters: ‘The cochlea goes up and down’ and ‘The body of the stone fire light is beautiful and beautiful.’ ‘What are we fighting about on the snail’s horn? It means, ‘Life is as short as lightning.’ Even after sending my friend off, this article lingered on the tip of my tongue for a while.
The original text of the story about a cow appearing in this poem is Zhuangzi’s Qiyang. There is a fable about the Cho tribe living on the left horn of a snail and the Man tribe living on the right horn fighting over territory and making great sacrifices to each other. It means ‘what a trivial thing it is.’ So how big is the universe?
Thanks to the James-Webb Astronomical Telescope (JWST), which began operation on July 12 of last year, new celestial bodies that had not been seen before were discovered, making the otherwise vast universe increasingly vast. When I was young, I estimated the size of the universe to be billions of light years and its age to be billions of years, but now it has expanded to approximately 93 billion light years and its age has increased to 13.8 billion years. This is also expected to increase as observation technology develops. Instead of this unfathomable universe, let’s try to estimate the solar system we live in.
When measuring the universe, the unit of distance is the light year. The distance light travels in one year is approximately 9.5 trillion km. On the other hand, when discussing the solar system, the unit called AU (Astronomical Unit) is used. It refers to the average distance between the sun and the Earth, which is approximately 150 million km. That is, the distance between the Sun and Earth is 1 AU, the Sun-Mars distance is 1.52 AU, the Sun-Jupiter distance is 5.2 AU, the Sun-Saturn distance is 9.58 AU, the Sun-Uranus distance is 19.18 AU, and the distance to the most distant planet, Neptune, is 30.07 AU. It is approximately 4.5 billion km. And the distance from Pluto, which has been downgraded from a planet to a dwarf planet, is approximately 50 AU, and Pluto-class dwarf planets and asteroids are being discovered one after another in the Pluto distance range, so this area is called the Kuiper Belt.
The area beyond the Kuiper Belt is an unknown world. It is not clear how far the solar system should be viewed. This is because the difference in distance is enormous depending on whether it is limited to the range of the solar wind or expanded to the range of the sun’s gravity. This is because the range of the solar wind is about 200 AU, which is four times the distance of the Kuiper Belt, while the range of the sun’s gravity is more than 50,000 AU.
Observations to date show that the solar wind does not reach beyond 200 AU, so this boundary is called Helliosheath, and the area beyond this boundary is called interstellar space. Voyager 1 and 2, launched in 1977, passed Heliosis in 2013 and 2018 and finally succeeded in entering interstellar space. However, it has not completely left the solar system. We still have to fly for hundreds or thousands of years to escape the hypothetical solar system shell layer called the Oort Cloud between 50,000 and 100,000 AU, when the Sun’s gravity is estimated to run out.
The Oort Cloud, presumed to be the home of Halley’s Comet, may no longer be a virtual space. This is because with the recent development of amazing observation technology, the possibility that it actually exists rather than being a virtual space is increasing. There was a surprise while investigating the Oort cloud. This is because a singer named ‘Younha’ sang a song on this topic. The lyrics are also surprising.
“While darkness was all I had, I ran until I was out of breath/ Because the edge of the border is not my end/ There might be something waving outside the fence, a star that no one knows/ With an overflowing heart, I break out of this orbit and break the shell of an explorer of a new path. Let’s throw it away~”
On my evening walk, seeing Jupiter shining brightly over the Taehwa River made me feel like I was living on Earth. As I savor the remaining two lines of Baek Ju-yi’s poem, I forget about my worries in this land. “隨富隨貧且歡樂(The wealth of the rich is the joy of the rich), 不開口笑是癡人(The blind and ignorant person)” “Whether you are rich or poor, you are happy just the way you are. Those who do not open their mouths and smile are fools.”
Jaeyoung Jeon, CEO of Corel Technology Co., Ltd., Doctor of Engineering
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