How big is the universe? How many galaxies are there? How many constellations are there?

The word "universe" probably originated from the famous philosopher Mozi in ancient China (about 468-376 BC). He used "Yu" to refer to the space in all directions, and "Zhou" to refer to the time from ancient times to the present. Together, it refers to everything in the world, no matter how big or small; Past, present or future; To approve or not to approve ... In short, everything is everything. From a philosophical point of view. People think that the universe has no beginning, no end and no end. However, we are not going to discuss this abstruse concept in depth, so let's leave it to philosophers to study. We might as well squint and use our existing science and technology to talk about the universe that we can understand and observe. People call it "our universe" or "total galaxy". According to the latest observation data, the farthest galaxy observed by people is 65.438+0.3 billion light years. That is to say, if a beam of light is emitted from the galaxy at a speed of 300,000 kilometers per second, it will take 654.38+03 billion years to reach the earth. This distance of 654.38+0.3 billion light years is the universe as we know it today. More specifically, the universe as we know it today, or its size, is a spherical space with the earth as the center and the distance of 65.438+0.3 billion light years as the radius. Of course, the earth is not really the center of the universe, and the universe is not necessarily a sphere. It's just limited to our current observation ability, and we can only know this extent. In this spherical space with a radius of1300 million light years, there are about1250 million galaxies that have been discovered and observed, and each galaxy has hundreds to trillions of sun-like stars. So as long as you do a simple math problem, it is not difficult for you to know how many stars there are in the universe we have observed. In such a vast universe, the earth is really a drop in the ocean and insignificant. How big is the universe as we know it? The universe contains all substances, including energy and radiation that humans have discovered, and everything that humans know and believe exists in space. There are hundreds of millions of celestial bodies in the universe, which are combined with each other very skillfully and regularly. Most stars make up galaxies, such as our solar system. Galaxies form the Milky Way again. There are at least 65438+ million galaxies in the universe. The space is very vast, and light can spread 300,000 kilometers in one second. In the Milky Way galaxy where our earth is alone, the width of the span is 65438+ million light years. There are 65438+ million galaxies in the universe, so how big is the universe? You still do the math. In order to explain the scope of the universe, scientists have calculated that the volume of 654.38+0.3 million earths is only equivalent to the volume of the sun, and the number of stars equivalent to the sun can reach more than 200 billion in the Milky Way. If the universe is regarded as a big ball with a radius of 1 km, then the Milky Way is only as big as a pill and is located near the center of the ball. In practical observation, people use high-powered radio telescopes to search for the quasar Sirius Giant 20 billion light years away. This is the farthest star that humans can really grasp at present, and it is also the largest range for people to understand the universe. Of course, it is not the actual edge of the universe. Because people's cognitive ability is limited I hope you are satisfied:) How many galaxies are there? Now humans have been able to observe125 billion galaxies, and each galaxy contains about 1000 billion stars. (For detailed scientific reports, see World Science 1 No.4, 999 and other magazines, and for popular reports, see Reference News 199919, etc. )

This year, scientists from the Laboratory of Astrophysics in Marseille, France and their Italian counterparts used an instrument called "visible multi-target spectrometer" in their observation. According to the different intensity of infrared light, astronomers discovered more than 8,000 galaxies, and found that about 1 0,000 of them were produced within/kloc-0.5 billion to 4 billion years after the Big Bang. There are 88 constellations.