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![]() " napisał w wiadomości ... On Mon, 07 Nov 2011 10:14:14 +0100, Szczepan Bialek rearranged some electrons to say: "The first observations of cosmic radio emission were made by the American engineer Karl G. Jansky in 1932, while studying thunderstorm radio disturbances at a frequency of 20.5 MHz (14.6 m). He discovered radio emission of unknown origin, which varied within a 24-hour period. Later he identified the source of this radiation to be in the direction of the centre of our Galaxy. From: http://encyclozine.com/science/astronomy/radio I understand that the frequency "varied within a 24-hour period". It is the "diurnal effect". And what about the 365 days period (annual effect)? S* It is not the frequency that changed, but the intensity. And not a 24 hour period, but 23 hours, 56 minutes, thus proving that the noise was not generated or varied by the earth's rotation. http://www.enotes.com/karl-jansky-reference/karl-jansky Yes. "His" transmitter "produced" many frequencies. But Karl G. Jansky was the pioneer in Radio Astronomy. Now are the spacecrafts. They use the two frequencies. I have found the link: http://chaos.swarthmore.edu/courses/...er_Anomaly.pdf ""It is also possible to infer the position in the sky of a spacecraft from the Doppler data. This is accomplished by examining the diurnal variation imparted to the Doppler shift by the Earth's rotation. As the ground station rotates underneath a spacecraft, the Doppler shift is modulated by a sinusoid." Probably in this paper is also the answer for my question: "And what about the 365 days period (annual effect)? Unfortunately I am not an expert in radio. Do you know the answer? S* |
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