What is Dark Matter?


Via Wikimedia Commons

Unseen dark matter

Scientists have been studying the universe for a long time, but they have yet to understand the mysterious substance known as dark matter. More than 80 percent of the universe is made of material humankind cannot observe directly. This 80 percent is made of dark matter. Dark matter does not emit light or energy, and cannot be seen with the naked eye. The existence of dark matter has not yet been totally proven, but recently a considerable amount of evidence has come to light that suggests its existence. Studies even show that a galaxy in our universe, known as galaxy Dragonfly 44, is most likely made entirely of dark matter. Contrary to what most believe, dark matter is not anti-matter and does not make black holes. But how do scientists know that there must be more matter out there?

Scientists can locate matter based on the movement of the stars, which is based on the gravitational pull from matter. This is how the galaxy Dragonfly 44 was located. It is possible that the other 80 percent of the universe could still be the matter we are already aware of, known as baryonic matter. Scientists still wonder what dark matter is made of, if it even exists at all. Scientists have narrowed down the material to the two most likely candidates. One is WIMPS, which stands for weakly interacting massive particles. The existence of this is also debated, but if they were to exist they would weigh 10 times the weight of a proton. The other possibility is neutrinos, which are particles that make up a substance other than matter, which is the main reason why these are a likely possibility.

Though dark matter makes up 80 percent of the total matter in the universe, dark energy makes up the main percentage of energy in the universe. After the universe began to expand after the big bang, scientists believed that the energy in the universe would eventually get used up, and would get smaller until it disappeared. Later scientists discovered that the universe was growing faster, and seems to have an endless supply of energy. This extra energy is called dark energy.

Like dark matter, dark energy emits no light and cannot be seen by the naked eye. It does not obey the normal laws of the universe, and therefore cannot be affected by gravity. It rapidly gains mass and does not grow in a specific direction, meaning its center will always be anchored to the same location.

Dark matter and dark energy remain a mystery today. Scientists are baffled by its unusual properties and lack of physics. Dark matter and dark energy are believed to make up the majority of the universe, and yet they continue to elude scientists. Science has come a long way in studying the matter that makes up our universe, and we hope to soon solve the mystery of these strange substances.