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  2. Doppler effect - Wikipedia

    en.wikipedia.org/wiki/Doppler_effect

    The use of the Doppler effect in astronomy depends on knowledge of precise frequencies of discrete lines in the spectra of stars. Among the nearby stars , the largest radial velocities with respect to the Sun are +308 km/s ( BD-15°4041 , also known as LHS 52, 81.7 light-years away) and −260 km/s ( Woolley 9722 , also known as Wolf 1106 and ...

  3. Relativistic Doppler effect - Wikipedia

    en.wikipedia.org/wiki/Relativistic_Doppler_effect

    The relativistic Doppler effect is the change in frequency, wavelength and amplitude [1] of light, caused by the relative motion of the source and the observer (as in the classical Doppler effect, first proposed by Christian Doppler in 1842 [2]), when taking into account effects described by the special theory of relativity.

  4. On the coloured light of the binary stars and some other ...

    en.wikipedia.org/wiki/On_the_coloured_light_of...

    Front cover Albireo, a well-known coloured double star.Compare the colour of other stars in . On the coloured light of the binary stars and some other stars of the heavens or in the original German Über das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels is a treatise by Christian Doppler (1842) [1] in which he postulated his principle that the observed frequency ...

  5. Relativistic beaming - Wikipedia

    en.wikipedia.org/wiki/Relativistic_beaming

    Only a single jet is visible in M87. Two jets are visible in 3C 31.. In physics, relativistic beaming (also known as Doppler beaming, Doppler boosting, or the headlight effect) is the process by which relativistic effects modify the apparent luminosity of emitting matter that is moving at speeds close to the speed of light.

  6. Doppler broadening - Wikipedia

    en.wikipedia.org/wiki/Doppler_broadening

    where is the observed frequency, is the frequency in the rest frame, is the velocity of the emitter towards the observer, and is the speed of light. Since there is a distribution of speeds both toward and away from the observer in any volume element of the radiating body, the net effect will be to broaden the observed line.

  7. Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Doppler_radar

    Doppler Effect: Change of wavelength and frequency caused by motion of the source. The formula for radar Doppler shift is the same as that for reflection of light by a moving mirror. [ 3 ] There is no need to invoke Albert Einstein 's theory of special relativity , because all observations are made in the same frame of reference. [ 4 ]

  8. Pound–Rebka experiment - Wikipedia

    en.wikipedia.org/wiki/Pound–Rebka_experiment

    Although the 14.4 keV recoilless emission line of 57 Fe had a half-width of 1.13×10 −12, the anticipated gravitational frequency shift was only 2.5×10 −15. Measurement of this minute amount of frequency shift, 500 times smaller than the half-width, required a sophisticated protocol for data acquisition and data analysis.

  9. Ives–Stilwell experiment - Wikipedia

    en.wikipedia.org/wiki/Ives–Stilwell_experiment

    In physics, the Ives–Stilwell experiment tested the contribution of relativistic time dilation to the Doppler shift of light. [1] [2] The result was in agreement with the formula for the transverse Doppler effect and was the first direct, quantitative confirmation of the time dilation factor. Since then many Ives–Stilwell type experiments ...