Detecting exoplanets through microlensing

There are many methods of detecting exoplanets. The method shown in this animation is called gravitational microlensing. This effect occurs when the gravitational field of a planet acts like a lens, magnifying the light of a distant background star. Astronomers can detect this magnification by measuring the brightness of the background star. The effect occurs only when the exoplanet's host star and the background star are almost exactly aligned.