Why do we see Dark Matter in the night sky?

For some days, one thing has been making me excited: what Black Matter in the space is. When the sun goes down, our universe becomes black with some light sources.
At the same time, if we ask other people what black matter that we see in the night sky is, 99% of normal people will say that it is just some empty space in the universe.

Let me stop you for a second, as if that space is empty, all the planetary bodies and stars should collapse. Maybe you will reply that these bodies are being held up together by gravitational force.

Well, yes, you are right that Star's gravity attracts planets to fall into it. But, due to continuous revolution around the star, the planet acquires the equilibrium state and keeps revolving around the star without falling into it.

Well, I am not going to talk about the physics behind the movement of stars and planets. There is something which is controlling all these stars, planets and galaxies. Yes, scientists determined some invisible matter which covers all the empty space in the universe. They named it "Dark Matter" or, in other words, "Black Matter."

Around 76% of matter in the Universe is Dark Matter. Yes, this non-observable matter is the reason behind the equilibrium of the Universe. There is a repulsive energy in the universe, known as Dark Energy which is responsible for further spaces between the galaxies. This energy is responsible for the universe's expansion. In 1920, Edwin Hubble was the first to notice that our universe is bigger than just Milkyway. Together, Dark Energy and Dark Matter consist 96% of the universe.

For over a decade, researchers in Sudan laboratory have been trying to identify the real proof of Dark Matter. Due to cosmic radiations, it's hard to detect the dark matter on the surface of Earth. So, around 2341 feet beneath the Earth's surface, scientists have made a lab in Sudan to carry out experiments on finding dark matter particles.

Now, the next is who made the scientists believe in dark matter. Well, the hunting of dark matter started about a century ago. An astronomer Fritz Zwicky looked up into the Coma cluster of galaxies and found that a huge amount of matter was moving in the galaxies. There was something which was affecting the motion of galaxies in the cluster, and something was holding matter inside the cluster. Taking it into consideration, Zwicky declared that an invisible matter is behind this phenomenon.

Vera Rubin, an American astronomer discovered a very strange activity in the galaxies' motion. She found that if a galaxy is a city, all the cars inside it are stars, and planets are without any traffic, then all the cars move at a constant speed.

She was one of the first people who actually pointed to the existence of Dark Matter. Dark Matter existence is simple. Let me give you a simple example. You can also try it at home.

Tie a small stone on one of the ends of a string. Hold another end with your hand and rotate the stone. You will see the circular motion of the stone. If I make you and the string invisible, only the stone will be moving. That's how our galaxies are moving. This proves the existence of Dark Matter.