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The Doppler effect changes the observed wavelength of radiation when a source and observer have relative motion along the line of sight.
supportedThe Doppler effect changes the observed wavelength of radiation when a source and observer have relative motion along the line of sight. Doppler measurements reveal radial velocity but not the full three-dimensional velocity by themselves.
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The Doppler effect changes the observed wavelength of radiation when a source and observer have relative motion along the line of sight.
supportedFor ordinary Doppler motion, successive wavefronts arrive more widely spaced when the source recedes and more closely spaced when it approaches.
supportedSpectrographs measure line positions with high precision.