Gravitational lens

Definition

Gravitational lensing is a phenomenon where light from a distant object is bent around a massive object between the light source and the observer. This effect can magnify and distort images of distant galaxies, providing valuable data about both the foreground and background objects.

5 Must Know Facts For Your Next Test

1. Gravitational lensing was predicted by Einstein's General Theory of Relativity.
2. There are three types of gravitational lenses: strong, weak, and microlensing.
3. Gravitational lensing can be used to detect dark matter by observing its influence on light from distant galaxies.
4. It helps astronomers estimate the mass of galaxy clusters, including the unseen dark matter.
5. The first strong gravitational lens was discovered in 1979, known as the Twin Quasar (Q0957+561).

Review Questions

• What theory predicts the phenomenon of gravitational lensing?
• How does gravitational lensing help in studying dark matter?
• What are the three types of gravitational lenses?

Related terms

Einstein Ring: A specific type of strong gravitational lens where light forms a ring-like structure around the massive object.

Dark Matter: A form of matter that does not emit light or energy, detectable through its gravitational effects on visible matter.

Galaxy Cluster: A large grouping of galaxies bound together by gravity, often studied using gravitational lensing to understand their total mass.