The existence of dark matter has been demonstrated through calculations and indirect observations. Its composition remains a mystery.
About 80% of the mass of the universe is made out of a material that scientists have never directly observed and they called dark matter. It does not interacts with light or any other elector magnetic waves. In 1950, a study of other galaxies like our Milky Way, showed that the universe contains a much greater amount of materials that we can see. Otherwise it would long since dispersed. Hence the conclusion increasingly widespread among astrophysicists that dark matter is a reality even though it has never been directly observed.
The study of other galaxies as our Milky Way, showed in the 1950s that the universe contains a much greater amount of material that we can see. Otherwise it would long since dispersed. Hence the conclusion increasingly widespread among astrophysicists that dark matter is a reality even though it has never been directly observed. Dark matter traces have perhaps been found by a particle detector to the International Space Station. But there is no scientific consensus on this experience.
The black holes , even gigantic, some dead stars or not active like white dwarfs , the brown dwarfs or neutron stars can constitute 80% of the mass of the universe that escapes us. It seems she is of a different nature than the material that we know, the baryonic matter said , made of protons, neutrons and electrons. Dark matter would consist of non-baryonic matter and probably WIMPs (weakly interacting massive particles) massive particles but weakly interacting with the “normal” matter which makes it very difficult to detect. Dark matter is also composed of hypothetical particles which is suspected as the Neutralinos , the axions and photinos .
There is another possibility, that the laws of gravity that have until now described and accurately predicted the movements of celestial objects, especially in our solar system are partly wrong. But until today nothing has come challenge gravity. And there is indirect evidence of the existence of dark matter.
Scientists calculate the mass of the objects in the universe by studying their trajectories. Thus in spiral galaxies like ours, the stars and gas from the center should move faster than objects outside of the spiral. And this is not the case, indicating that galaxies are composed of a much greater mass than we can see. The groups of galaxies which are set by the force of gravity would be dispersed if the masses involved were only measured by the matter we see. Finally, Albert Einstein demonstrated that massive objects in space have a distorting effect on the light and it allowed astronomers to create a dark matter map in the universe .
And beside the mystery of dark matter exists also the mystery of dark energy . After the Big Bang , the universe began to expand high-speed, scientists have calculated that at one point he should have started running out of energy to keep growing. This is not the case and the universe grows even faster now than in the past. This seems possible only if the universe has enough energy to overcome gravity, an unknown energy: dark energy.
There is unidentified matter spread acorss the universe which is more than the matter that we know of. This mysterious thing does not interact with any of frequencies of electromagnetic spectrum. So we are not able to spot them, but we can detect it’s gravitational attraction.