Einstein cross

Facts for Prelims (FFP)

 

Source: LiveScience

 

Context: Astronomers have discovered a rare example of an “Einstein cross,” a phenomenon predicted by Albert Einstein in 1915.

  • In this case, a foreground elliptical galaxy, located around 6 billion light-years from Earth, has distorted and split a beam of light from a background galaxy about 11 billion light-years away.
  • The result is a pattern of four blue smudges around the orange glow of the foreground galaxy.
  • The background light likely originates from a quasar, a young galaxy with a supermassive black hole at its core emitting intense radiation.

 

Einstein’s theory of general relativity explains how massive objects warp space-time, and the strong gravity of the foreground galaxy curved the light from the quasar, creating the Einstein cross pattern.