Have you ever wondered if there is something bigger than us? Have you ever imagined that he was invisible? Maybe, but probably not, right? Well, as science has theorized time and time again, there is another problem. This something is Dark Matter. According to scientists, dark matter occupies about 25% of the universe. The rest is dark energy (which takes up about 70%) (and visible matter (which takes up about 5%). It may seem like we know a lot about this thing we call dark matter, but in reality, it's not. We basically know three things: there's something there, it interacts with gravity, and there's a lot of it.Say No to Plagiarism Get a tailor-made essay on “Why Games.” violent video shouldn't be banned"? Get original. You're probably wondering: "Basically, it's an invisible substance that helps hold galaxies together. her eye on the history of spiral galaxies We can learn a lot about galaxies from the way they rotate. As she observed them, she noticed something unusually strange. The galaxies were moving at a speed. alarmingly faster than expected In the 1600s, Johannes Kepler discovered that the farther away a planet is. the slower the sun rotates. Later, Newton put numbers to this and came up with equations to find the mass of the sun by finding its gravity. You can't actually see the nebulae moving, but you can measure their Doppler shift. Rubin expected nebulae to move in a pattern similar to that of solar systems. But what she found was that even at the outskirts of galaxies, the speed was uniform, or even faster. When you look at galaxies, you can clearly see fewer stars outside the galaxies. So the only way to make the equations work was to have more material. Scientists have dubbed this dark matter. Over the years, experiments have only confirmed dark matter. Scientists listed everything they could think of. They thought of cold gases, dust and dead stars. They were thinking about rogue planets and even strange subatomic particles. The existence of these particles was predicted in theories of quantum mechanics, but they had never been observed before. Scientists tested this dark matter to see if it gave off anything that normal matter would give off. Nothing was found, but they eventually crossed everything off the list. The only thing left were these crazy subatomic particles. There are many theories about what dark matter actually is. Dark matter could not exist, for example. Many scientists believe that it does not exist, but without it the calculations simply do not work. It could be MACHO (MAssive Compact Halo Objects). These include black holes, brown dwarfs and neutron stars. Yet there is too much dark matter for any of this to be MACHO. These could be neutrinos, which are small subatomic particles that do not react with normal matter. Tens of thousands of these elements pass through you every second. However, they move faster than the speed of light, which would make them extremely hot. Dark matter has also been proven to move much slower than the speed of light. The following two theories are the most likely. Dark matter could actually be a subatomic particle called Axion. However, we never ?, 5(1), 12–19.