The universe is vast, and the solar system is just one of the countless galaxies. For the whole universe, the solar system is tiny, and the earth is even more insignificant dust. Human beings were born on the earth, a dusty planet of life. Human beings have to say that they are a civilization that constantly creates miracles. It took only millions of years from birth to evolution and growth to civilization. It took only 200 years from the beginning of the industrial revolution to the development of science and technology to going out of the earth. Human beings are amazing.
With the help of the detector, we know more and more about the solar system, but we know very little about the edge of the solar system. Because it is too far away, it takes a long time for the detector to reach the edge of the solar system. In the past, scientists thought that Pluto would be out of the solar system, but later, scientists found that there is the Kuiper belt outside the solar system, Beyond the Kuiper belt, there is also the Oort nebula, which is as thick as one light year. It surrounds the solar system, so the diameter of the whole solar system is more than one light year.