Over the past few decades, scientists have been conducting research to improve our understanding of the Universe.
Matter is any substance that has mass and occupies a physical space. All of the matter around us (including galaxies and planets) make up around 5% of the known universe. 25% is dark matter and around 69% is dark energy.
This suggests that the matter we interact with only makes up a tiny portion of reality. Scientists are not sure about what dark matter and dark energy are, or how they work. However, they are sure about their existence.
Scientists realised that there is not enough normal matter because the gravity of the visible matter is too weak to form galaxies and other complex structures. It became clear that there was a dark substance inside and around galaxies, which has a gravitational effect on visible matter. This dark substance is called dark matter.
Dark matter does not appear to interact with observable electromagnetic radiation. Scientists can only detect dark matter from the gravitational effect it has on visible matter. So, they detect matter through gravitational lensing.
Regions with a high concentration of dark matter bend light that passes by, which distorts the images of our telescopes on Earth.
In regions with low dark matter present, the images will not be distorted.
More is unknown than known about dark energy. Scientists are unable to detect it or measure it directly, however, we can see how it affects the Universe’s expansion. Astronomers in the 20th century made observations which suggest that distant galaxies are moving away at an increasingly faster rate.
Dark energy is the name given to the mysterious force that is accelerating the expansion of our Universe over time.
The rate of the Universe’s expansion and the rate of acceleration can be calculated by making observations. These measurements, along with other scientific data, have confirmed the existence of dark energy. They have also enabled scientists to provide an estimation of just how much of the substance exists.