Stars like our Sun are formed from the gravitational collapse of prestellar cores. However, prestellar cores have strong magnetic fields that need to be weakened for gravitational collapse to take over allowing a star to form. By observing two tracer molecules in a prestellar core, researchers have observed ambipolar diffusion, a velocity discrepancy between ions and neutral particles. This process weakens the magnetic field of the core, which eventually collapses to form a protostar.