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Suppose a spacecraft is in a circular orbit about a distant planet. the spacecraft emits a continuous radio signal with a wavelength of 6m. The signal's wavelength varies between 5.99969m and 6.00031m; the period of variation (full period of wavelength) is 5 hours. What is the mass of the planet? Assume that you are located in plane of the spacecraft's orbit and knowing that circumference is 2piea (a = radius) and that speed = distance / time.

Thanks in advance!

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# Calculation of a planet's mass via wavelengths

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