Here’s all the evidence, experiments and theories which prove the existence of dark matter. All the information in this article was taken from credible sources and Youtube channels (ex. Fermilab and Caltech magazine) All links to articles and websites referred to while making this will provided down below.
The first observation of Dark Matter:
In the year 1933 a scientist at Caltech, Fritz Zwicky was observing through the Mount Wilson observatory the visible mass of cluster galaxies, when he noticed that the visible matter which was making up the cluster was far too small to create a strong enough gravitational pull to keep the galaxies in the cluster bound together, so he assumed there must be something that he couldn’t see some other matter which was contributing to the mass and held the galaxies in the cluster together. He called this ‘dunkle Materie’ or ‘Dark Matter’ .
Later in the year 1970, Vera Rubin was measuring the velocity curves of a galaxy (This means that she was looking at different stars in the galaxy and seeing how fast or slow they move compared to their distance from the center of the galaxy). So you would have guessed that is a star is further away it would be moving slower as the pull of gravity is less the further away you go right? But instead what she found was rather flat velocity curves which showed that the speed of the stars barely changed as you went away from the galaxy’s center! To further add to these these bizarre findings, it was seen that the gas surrounding the galaxy, was moving at a faster velocity that the galaxy itself! So what could have been causing this? There must have been some mass other the galaxy central supermassive blackhole which caused the stars and the gas far away from the center to move faster, this matter is thought to be Dark Matter
Visible Evidence of Dark matter seen in Galaxy Clusters:
Coma Cluster: The left image shows a picture of the Coma Cluster and the right shows an x-ray image of the gasses in the cluster. As we can see the gasses are concentrated at one spot. They stay there and do not evaporate off, even though there is no exact visible object anchoring the gases. This phenomena can only be explained by the presence of something we cannot see, something that is anchoring the gasses in place. This something is believed to be Dark Matter!
Bullet Cluster: The Bullet cluster galaxy is an amazing way to see the interactions of dark matter. The bullet cluster has two galaxies which ploughed through each other (one went through another), that's how we see the small pink triangle right, that triangle form the galaxy slow down as another galaxy pushes though it. But although the gases slow down, when we do gravitational lensing we see that most of the mass if actually concentrated outside the gases, the mass is concentrated most at the blue stuff, which is dark matter, as it is not visible. This is evidence to show that dark matter doesn’t interact with light or the gasses in the cluster, but it does interact via gravity, because gravitational lensing shows us the concentrated mass of the dark matter.
Conclusion: References and topics which I will write further on.
Further topics on Dark Matter which I will write on:
- Dark Matter: Reason of our existence
- MAGIS-100: The epitome of science: Using Quantum to search for Dark Matter
- Axions: discovery and a brief on Strong field theory
- Potential Candidates for Dark Matter: WIMPs, axions, sterile neutrinos and more
- Experiments set up to prove the existence of Dark Matter
References and Sources:
