Gravitational Lensing: Light Bent by Massive Objects

  1. Gravitational lensing occurs when massive objects like galaxies bend light through gravity.
  2. It was first confirmed during a 1919 eclipse, proving Einstein’s general relativity.
  3. Lensing can magnify distant galaxies, acting like a natural cosmic telescope.
  4. Strong lensing produces arcs, rings, or multiple images of background objects.
  5. Weak lensing subtly distorts galaxy shapes, helping map dark matter distribution.
  6. Microlensing happens when stars or planets briefly bend light, revealing hidden objects.
  7. Galaxy clusters are powerful lenses, magnifying some of the faintest galaxies ever seen.
  8. Lensing allows astronomers to study dark matter, which bends light despite being invisible.
  9. It helps measure the expansion rate of the universe through time delays in lensed quasars.
  10. Gravitational lensing turns massive cosmic structures into tools for discovery.