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![]() Uzytkownik "Rob" napisal w wiadomosci ... Szczepan Bialek wrote: You all know that the frequency from a satellite is changing. Does anybody know if the frequency from a spacecraft reacts on the orbital speed of the Earth. S* No, what you hear is mainly due to the orbital speed of the satellite around the earth. The satellite has a speed relative to the observer, and the resulting doppler shift makes the apparent frequency of the satellite change. When using a linear transponder, the situation becomes more complex because both the speed relative to the transmitter and the speed relative to the receiver have to be taken into account. I have found the two old measurements: "In 1818 Arago found that the refraction of a prism for star light was the same for light incident in the direction of the earth's orbital velocity v as for that coming in the opposite direction. This unexpected null result was explained that same year by Fresnel's ether-dray theory, which assumed partial ether entrainment in transparent media by an amount depending upon the first power of v." From: http://www.3rd1000.com/chronoatoms.htm And: 2. Vogel, H. C., "On the spectrographic method of determining the velocity of stars in the line of sight", Monthly Notices of the Royal Astronomical Society, Vol. 52, p.87, 1891 "The first result of any importance which the spectrographic method furnished was the proof of the influence of the Earth's motion on the displacement, which the earlier direct observations had failed to show with certainity. [...]" From: http://adsabs.harvard.edu/abs/1891MNRAS..52...87V Who was right: Arago or Vogel? The spectroscopy and the spectrography are not accurate. The radio waves are. S* |
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