One way that astronomers detect planets outside of our solar system (called exoplanets) is commonly referred to as the radial velocity method. This relies on the __________ ___________ to cause shifts in the spectral lines of stars as the stars perform tiny orbits around the center of mass of the host star and its orbiting planets. Those tiny orbits cause the stars to periodically (and therefore predictably) move closer to and further away from our solar system. Luckily, this method only relies on the motion of the star; its physical distance from us does not impact the resulting shifts

One way that astronomers detect planets outside of our solar system (called exoplanets) is commonly referred to as the radial velocity method. This relies on the _ to cause shifts in the spectral lines of stars as the stars perform tiny orbits around the center of mass of the host star and its orbiting planets. Those tiny orbits cause the stars to periodically (and therefore predictably) move closer to and further away from our solar system. Luckily, this method only relies on the motion of the star; its physical distance from us does not impact the resulting shifts