Illustration of gravitational lensing
Date: 03 November 2010
Depicts: Gravitational lensing
The light from a distant galaxy is bent by the presence of a foreground galaxy, in a process called gravitational lensing. The foreground galaxy (blue) is seen by optical telescopes, while the light from the background galaxy (red) is observed as a distorted image (pink) at far-infrared and sub-millimetre telescopes - the distortion is so strong that the background galaxy is actually multiply imaged. In the example depicted here, the light from the distant galaxy has taken 11 billion years to reach us, compared with just 3 billion years for the much closer foreground galaxy.
Last Update: 1 September 2019