Dark Matter

What if someone told you that around 80% percent of what is in space is not something that scientists can actually observe? Well, I am telling you this right now and extraordinarily this is actually true. How is that possible that most of what is in space is not something we can see? Well, this "thing" that takes up so much of space is something called dark matter.

What is dark matter?  And how do we know that it exists if we can't see it?

Well, in the 1950s, there were studies done which showed that the universe contained more matter than is actually seen by the naked eye. The universe has an abundance of baryonic matter, but if dark matter is baryonic or not is something we do not know about. Some possibilities of "dark matter" could be due to brown dwarfs, white dwarfs, neutrinos or even black holes, all of which are fairly heavy and dense. Other scientist believe that dark matter is composed of non-baryonic matter such as WIMPS (Weakly interacting massive articles). WHIPS have ten to a hundred times more mass of a proton but their weak interaction with normal matter makes it all the harder to detect. The foremost candidate in this group is the Neutralino which is heavier and slower than neutrinos, however, they are yet to be found.

Scientists are able to tell that there is such thing as dark matter by examining stellar object's motion. In the 1950s, astronomer who were studying spiral galaxies, expected to see the center of the galaxy moving faster than the edges. Instead, they found that both the edge and center moved at the same velocity, proving that the galaxies had more mass than could be seen. Cluster of galaxies would fall apart if the only mass they contained were the ones we are able to see; this is due to the lack of gravitational pull if it did not have enough mass. With the help of Albert Einstein who proposed that massive objects can actually have enough gravity to pull light, causing light to bend and distort, scientists are now able to create a probable dark matter map.