|MadSci Network: Physics|
Hello again Tiago. Thank you for clarifying. It seems I missed the entire point of your question. Sorry about that. Back to your question - The frequency of the broadcast would definitely change. It would get slower as the speed of the space craft sending it got faster. As the space craft accelerated, the equipment we would need to capture a television transmission would change. It would fall from the television frequencies to the shortwave radio frequencies, then down to the AM radio frequencies, and finally down to the aircraft and maritime shipping commercial frequencies. Once the frequency slips below that used by aircraft and commercial shipping bandwidths, we'd have to start making our own reception devices, because there aren't any commercial applications of communication using frequencies below that point. Television transmissions are not instant in nature. They have a starting time and an ending time, and are emitting a stream of photons from the beginning until the end. Since the source of the signal is moving away from Earth at near light-speed, the signal near the end of the transmission must travel farther to reach us than the signal at the beginning of the transmission. So we would see a slow motion image on our television receiver. As you pointed out, this would be a Doppler effect, not an effect of time dilation. Again, I apologize for not reading your first question more carefully, and hope we're now on the same (here it comes) wavelength. Layne Johnson
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