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DaveC426913
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I think you misunderstand. Reread. D_H is clever enough to understand how geostat sats work.ruko said:Easy. Geo satellites are in orbit traveling at about 6900 MPH with an altitude of about 22,000miles. The exact same mechanism holds for satellites in low or high Earth orbit. It just so happens this altitude and speed produces an orbital period that matches Earth's period of rotation. To us the geo looks like it is motionless but it is definitely moving very fast.
His comment was in the context of an Earth-based frame of reference, where the motion of the satellite is zero. It is a valid FoR, but one must create a force to explain what holds these stationary objects up.
ruko said:Something I'm curious about geosats. Are the antennas on them directional? If so the satellite would have to rotate 360 degrees on its axis during every orbit to keep the antennas facing the earth. Just like the moon keeps the same side to Earth by rotating during the journey.
I'm pretty sure most satellites are spun to give them stability. I guess gyroscopically, that would mean they do not rotate (i.e. their rotational axis points to the same position on the celestial sphere permanently).
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