5 Facts About Dark Matter

There’s a movie out with Meryl Streep called ‘Dark Matter’ that focuses on a young man with a scholarship from China traveling to Salt Lake City to become a graduate student in cosmology. As he comes closer to exploring the origins of the universe, politics play a role in his progress. It’s actually based on a true story, but it made me wonder what exactly dark matter is, perhaps this article will shed a bit of light on the subject.

What is Dark Matter?

In the world of astronomy, dark matter is the form of matter that cannot be detected by the electromagnetic radiation that it emits. The only way that you know it exists is from the assumption of its presence due to the gravitational effects that it has on background radiation and matter that we can see. After analyzing structures larger than galaxies and taking a closer look at Big Bang cosmology, it is believed that dark matter makes up a great deal of the mass associated with the universe that we can still detect.

5 Facts About Dark Matter

1.    In an effort to explain ‘missing mass’ in the orbital velocities of galaxies in clusters, Fritz Zwicky began the conversation of dark matter in 1934.

2.    Before Zwicky’s theories, some scientists had observed the presence of dark matter in the universe, including the rotational speeds of galaxies and other features of the universe, including the Bullet Cluster, which represent two colliding clusters of galazies. The studies of the Bullet cluster hit the headlines in 2006 and have been uised to prove the existance of dark matter.

3.    Those who study dark matter use observations of structures that are larger than galaxies, as well research Big Bang cosmology to assess the amount of total mass-energy of the parts of the universe we can see is comprised of 23% dark matter.

4.    Scientists have estimated the distribution of dark matter and dark energy in the universe according to the past and the present. 13.7 billion years ago, they believe the universe was comprised of dark matter (63%), neutrinos (10%), photons (15%), and atoms (12%). Today, scientists estimate the universe is comprised of dark energy (72%), dark matter (23%), and atoms (4.6%).

5.    Astronomers use tools and equipment, such as the Hubble Space Telescope to identify the presence of dark matter. For instance, strong gravitational lensing was observed in Abell 1689 by using the Hubble Telescope. A gravitational lens is established when the light from a very distant, bright source (like a quasar) is somehow “bent” around a very large object (like a cluster of galaxies) between the source object and the observer. When this process takes place, it is called gravitational lensing.