The Doppler Effect: A Way to Discover Exoplanets

Artist’s impression of an exoplanet. Source: PHYS ORG

The same Doppler Effect that changes a siren’s pitch as it passes by an observer is used by planetary scientists to find exoplanets. Exoplanets orbit other stars outside our solar system. They are new worlds that may be habitable. The technique is known as Doppler spectroscopy, also referred to as the radial-velocity method, or the “wobble method.”