How does gravitational lensing work?

Gravitational lensing is the bending of light by massive objects in space.

When light from a distant object passes close to a massive object, such as a galaxy or black hole, the gravitational pull of the object can bend the path of the light. This causes the light to be distorted and appear as if it is coming from a different location. This effect is known as gravitational lensing.

There are two types of gravitational lensing: strong and weak. Strong gravitational lensing occurs when the light is bent so much that it forms multiple images of the same object. Weak gravitational lensing occurs when the light is only slightly bent, causing the object to appear distorted.

Gravitational lensing has been used by astronomers to study the properties of massive objects in space, such as galaxies and black holes. By observing the way that light is bent around these objects, astronomers can determine their mass and structure.

In addition to studying massive objects, gravitational lensing has also been used to detect and study dark matter. Dark matter does not emit light, so it cannot be directly observed. However, its presence can be inferred by observing the way that light is bent around it through gravitational lensing.

Overall, gravitational lensing is an important tool for astronomers to study the properties of objects in space and to learn more about the mysteries of the universe.