Simulation of Gravitational Microlensing

This simulation shows the 22-year journey of a star moving through space and passing directly in front of a more distant background star. All stars drift through space. Occasionally, a star lines up perfectly in front of a more distant star. The momentary alignment magnifies and brightens the light from the background star, an effect called gravitational microlensing. In April 2005, ground-based gravitational microlensing searches detected a star that had aligned perfectly with a distant background star. L