Our universe is vast. The diameter of the observable universe is 93 billion light-years. In the vast universe, it is full of infinite mystery. Now, I’m going to take you to four amazing facts about the universe.
1、 The void of the universe
Besides black holes, there are many holes in the universe. Cavity refers to the space between fibrous structures, which together with fibrous structure is the largest scale structure in the universe. In large and dense starburst galaxies, stars and nebulae pour into the central black hole like a waterfall, forming explosions. Hundreds of millions of years later, the inner part of the galaxy was swallowed up, and the outer part of the galaxy was violently dispersed, thus forming a hole.
Most of the observed cavities are hundreds of millions of light-years in diameter. There are very few stars, nebulae and other materials, and the reason for their formation is still unclear.
2、 The temperature of the universe
There is also temperature in the universe. Even if we take away all the stars in the whole universe, you will see warm red light. This is the cosmic microwave background radiation, which is the thermal radiation left behind by the big bang. The temperature is about 3K.
According to the big bang theory, at the beginning of the big bang, stars and galaxies had not yet formed, and the universe was full of dense, high-temperature hydrogen plasma and radiation. With the expansion and cooling of the universe, ions and electrons combine to form neutral particles almost instantaneously. From then on, photons begin to be unimpeded in the universe, instead of being continuously scattered by plasma.
This event is called photon decoupling, and the universe suddenly becomes transparent at this moment. When photons decouple, the photons coming out of chaos travel through the universe with the information of creation, until they collide with human detectors. It is a kind of electromagnetic radiation that fills the whole universe.
3、 The speed of light is the fastest in the universe
According to the current level of human science and technology, the speed of light as high as 300000 kilometers per second is the fastest speed in the universe. If you use the speed of light to circle the earth, you will find that it can circle the earth 7.5 times a second, but even if the speed of light, it will take more than four years to go to the nearest neighbor star. However, scientists believe that no matter can reach the speed of light at present, and it is far away to reach the speed of light in the future.
4、 The number of celestial bodies in the universe
The diameter of our galaxy is about 100000 light-years. If you think about it, our earth is only 150 million kilometers away from the sun, Neptune, the farthest of the eight planets, is only 4.5 billion kilometers away from the sun, and the nearest star is 4.22 light-years away, you can imagine how huge our galaxy is. However, our neighbor Andromeda galaxy is twice the size of the Milky way.
For the universe, galaxies are the basic unit of the universe, just like the family of society. Our galaxy is a large family of stars, during which there are about 250 billion stars, and there are countless planets, asteroids and other celestial bodies around the stars.
However, in our universe, there are about 2 trillion galaxies only in the observable part. Even if calculated according to the probability of 1%, there are at least billions of living planets and satellites, the number will increase several times. If the Milky way is really like this, what about the universe?
What do you think of these four amazing facts about the universe? Welcome to comment area.