Dark Matter in the Galaxy

The world we see and are familiar with consists of Normal Matter. Everything made out of atoms is considered Normal Matter. Normal Matter makes up of five percent of all matter. So what makes up the rest of the ninety-five percent? Dark Energy makes up roughly seventy percent of our universe while Dark Matter makes up the last twenty-five percent.
What is Dark Matter? Dark Matter is the only explanation we have for why our universe expands in the way it does, but we have no idea what makes it up. Dark Matter does not clump up like Normal Matter, so it does not make up anything that we find important such as planets and life-forms. Instead Dark Matter is spread out across our galaxy, extending for millions of light years. The spread of Dark Matter is much more significant than normal matter, for example our Milky Way is only about a few thousand light years thick and about 100,000 light years in diameter, however that is just what we see, Normal Matter. Dark Matter extends even further than Normal Matter by millions of years in all directions. Both of these types of matter affect gravitation, but by how much?
Normal Matter mass, such as objects like the sun, is what makes up most of gravitational pull, Dark Matter has been calculated to have half the affect the sun does on earth. To really see Dark Matter in action you must take a step back and look at our entire galaxy. Dark Matter works in a much broader aspect. It is easier to see Dark Matter’s effect from further away because of how it extends further than Normal Matter. Given Normal Matter’s gravitational pull, stars closer to the center of a galaxy should travel at a faster speed then stars further away from the center. However, in the 1970’s Vera Rubin found that all stars...

... middle of paper ...

....d.). Retrieved from http://science.howstuffworks.com/dictionary/astronomy-terms/dark-matter.htm
Chase, S. (n.d.). Retrieved from http://math.ucr.edu/home/baez/physics/Relativity/GR/dark_matter.htmlhttp://www.washingtonpost.com/blogs/innovations/wp/2013/11/07/dark-matter-what-we-know-and-why-you-should-care/
Al-Khalili, J. (2013, November 18). How close are we to finding dark matter?. Retrieved from http://www.bbc.co.uk/news/science-environment-24987749http://www.seasky.org/celestial-objects/dark-matter.html
Rubin, V. (n.d.). Retrieved from http://www.indiana.edu/~geol105/images/gaia_chapter_1/dark_matter_in_the_universe.htmhttp://www.learner.org/courses/physics/unit/text.html?unit=10&secNum=2
Charles, C. (n.d.). Retrieved from http://www.huffingtonpost.com/2013/12/08/dark-matter-black-holes_n_4408646.htmlhttp://space.about.com/od/deepspace/a/What-Is-Dark-Matter.htm