What we can see in the sky either with the naked eye or with optical instruments is only a small fraction of what we know as the universe. Why? The rest of the universe does not emit any kind of light in any spectrum that we can detect; however, the presence of this matter and energy is detected by the effect it has on other matter in the universe. When light from stars passes through a region with dark matter, the light gets distorted and bends, making the star appear in a different location in space. This is called gravitational lensing, an effect usually associated with normal matter. Scientists have detected gravitational lensing in regions where there is no normal matter, leading them to conclude that dark matter is present. This material comes in two forms: dark matter and dark energy. Dark matter and dark energy are the big scientific mysteries in cosmology, the study of the origin of the universe, among other things.
ፍትህ ለሁሉም / Justice for All