An invisible universe, an impossible substance holding the ever expanding universe together on wire thin strings, everything you can see, on Earth or in space, is almost totally dominated by one substance; dark matter. For over 50 years, scientists have been trying to comprehend this massive material that is thought to take up 85% of the almost infinite universe. Today you will be learning about the mysterious and puzzling material that has broken scientist’s basic understandings of physics.
The first question you might be asking is “what is Dark matter?” The truth is, I don’t know, nobody does, but we certainly know that it is out there. We know more about what it isn’t than what it is, so I will tell you all that I know. Dark matter is a hypothetical substance that does not emit, absorb or reflect light or energy. So we cannot see or study it directly. It does not collide with itself, but weakly interacts with other large objects. Every dark matter particle, is thought to have about 100 times the mass of a proton. We know that dark matter is affected by two things, gravity and heat. When studying dark matter, scientists at Carnegie Mellon University realised that when stars formed, the intense heat would force the dark matter away from the centre of the galaxy.
You may be asking yourself why dark matter is so important if we can’t even prove that it exists? Well imagine if you couldn’t see or feel your body, except for your head and face, and then 80 years later, you found out your arms, legs and torso suddenly existed, yeah, it would be a pretty drastic change. Plus, this also is the thing holding the entire universe together, if there was no dark matter, everything would fall out of orbit, there would be no space, no stars and no sun. This is all because, the universe is spinning at such a speed that the gravity produced by normal matter (liquids, solids and gases) could not possibly hold the universe together, so there must be something else in between everything in the universe, the logical answer scientists came up with is dark matter. Dark meaning not actually dark, but mysterious.
An intense point of interest for scientists studying dark matter is this massive spiraling clump of dark matter, which is going to collide with Earth, and it is called the dark matter hurricane. Even though it is going to collide with earth, do not be alarmed, it will barely even affect us. The most it will do is give us a chance to get a very close look at dark matter, so we can study it further.
The incredible search for dark matter started in 1970, when astronomer Vera Rubin was studying the rotation of galaxies. She had predicted that, because there was less mass and less gravity near the outside of the galaxy, that the outside would move slower, but what she found was very, very interesting. She found that the galaxy moved like a disk, equal on the inside and outside of the galaxy. Which didn’t make sense. She concluded that there must have been some invisible substance keeping the mass on the outside equal to the inside. She was said to be the first to even consider dark matter. Scientists thought that this was impossible, so they started thinking, what on Earth could be out there. They came up with many different options, but one by one, they were all disproven. These things included cold gas, dust clouds, dead stars rogue planets and even black hole fragments.
Many studies are being done in order to prove the ever expanding theory of dark matter. Experiments at the Large Hadron Collider in Cern Switzerland are working to detect dark matter through colliding dark matter with the nucleus of normal matter particles, which would release a small detectable wave. Beneath a mountain in Italy, the LNGS’s XENON1T is hunting for signs of interactions with dark matter, and a project called “the icecube operation” is looking for dark matter under the ice surface of Antarctica.
It seems that no matter how far we come in the field of research, we will never know enough. The humans drive for knowledge, drive for answers will never stop. We will always find things we don’t understand. So don’t fear the unknown, replace it with curiosity and a drive for answers.