In the vastness of the universe, the earth is nothing but a small existence. On February 14, 1990, the Voyager 1 probe took a picture at a distance of 6.4 billion kilometers from the Earth, showing that the Earth occupies only 0The 12-pixel shape was named a "dull blue dot" by Carl Sagan. This ** not only reveals the insignificance of the earth in the universe, but also inspires people to think about the infinite vastness of the universe.
Voyager 1 is an unmanned space probe launched by NASA on September 5, 1977. It takes advantage of the special geometrical arrangement of the planets to explore Jupiter and Saturn through the planetary gravitational slingshot effect, providing us with valuable data on these planets. However, during the exploration of Saturn's moon Titan, Voyager 1 deviated from its original orbit and became the first man-made object to enter the outer solar system.
On the scale of the universe, the Earth is so tiny. From the "faint blue dot"**, we can hardly tell what the Earth really is. This ** prompts people to start thinking that our lives, our struggles, our dreams, and our fears all happen in this inconspicuous little dot. It reminds us that the earth is our only home and that we should cherish and protect it.
Our solar system itself is huge. Its radius is about 1 light-year, which is equivalent to a 2-light-year sphere. The outermost part of the solar system is the Oort cloud, a huge group of celestial bodies that surrounds the solar system. At the current speed of human spacecraft, it will take at least tens of thousands of years to leave the solar system and cross the Oort cloud.
However, on a larger scale, the solar system is just a speck of dust in the Milky Way. The Milky Way is about 10-160,000 light-years in diameter and has more than 200 billion stars. Our Sun, along with countless other stars, revolves around the center of the Milky Way.
In the universe, the Milky Way is just one of many galaxies. It is part of the Local Group of Galaxies, which consists of about 50 galaxies with a diameter of about 10 million light-years. However, the local group of galaxies is also only part of a larger structure, such as the Virgo Cluster and the Laniakea Supercluster. These massive structures in the universe, such as galaxy clusters and superclusters, demonstrate the true scale of the universe.
There are also larger structures in the universe, such as the Great Wall of the Universe and the Pisces-Cetus Supercluster complex, which are a vast web of fibers made up of countless galaxy clusters that make up the large-scale structure of the universe. These structures can be hundreds of millions of light-years in diameter, reflecting the vastness and complexity of the universe. This huge structure highlights the uneven distribution of matter in the universe and is also an important clue to our understanding of the evolution of the universe.
The universe we can observe so far is a spherical space with a diameter of about 93 billion light-years. This limit is determined by the speed of light – beyond this range, the light emitted by them has not yet had enough time to reach our eyes. Therefore, the boundaries of the observable universe do not represent the true size of the universe, but rather the limits of what our current technology can reach.
In cosmology, there are a large number of unsolved mysteries. For example, the exact size of the universe, the specific process of the universe, the nature of dark matter and dark energy, etc. Every astronomical observation and space exploration has the potential to uncover new mysteries of the universe and advance our deeper understanding of the universe.
From the "faint blue dot" photographed by Voyager 1 to the exploration of the Milky Way and superclusters, our understanding of the universe continues to expand. Although we may seem small in the universe, our spirit of exploration and technological progress have enabled us to understand this grand universe more and more deeply. In the future, with the development of science and technology and the emergence of new theories of the universe, our understanding of the universe will be more comprehensive, and perhaps more secrets about the universe will be revealed.