Special geostationary orbit condition

AI Thread Summary
Geostationary satellites in circular orbits at the equator have no distinction between true anomaly, mean anomaly, and eccentric anomaly. The angles related to their position, including Greenwich sidereal time and longitude of ascending node, are all measured in the equatorial plane. For a satellite to remain fixed over the equator at a specific longitude, the equation Ω + ω + f = θ + λ_{SS} must hold true, along with the condition that the rates of change of true anomaly and sidereal time are equal. The discussion emphasizes the importance of Kepler's laws, specifically that the orbit must have an eccentricity of zero. The participants seek clarification on calculations and confirm that understanding the relationships between these angles is crucial for further analysis.
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For geostationary satellites moving in circular orbits in the equatorial plane, there is no distinction between the true anomaly f, the mean anomaly M, and the eccentric anomaly E. For geostationary satellites, the angles \theta=Greenwich sidereal time, \Omega = longitude of ascending note, \omega = argument of periapsis and f =true anomaly are all measured in the plane of the equator. Show that for such a satellite ro remain fixed on the equator at the sub-satellite point with east longitude \lambda_{SS} it is necessary that

\Omega + \omega + f = \theta + \lambda_{SS}

and that \frac {df}{dt} = \frac {d \theta}{dt}

Include in your argument an illustration showing the equinox of all angles involved.

Here' s what I know, i = 0. From Kepler's laws, the orbit must have e = 0. From these, where do I go? What is the first thing I could calculate?

Any help would be greatly appreciated guys...I am lost here. :confused:

James
 
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Anyone?Just give me something guys.Please..I'll work on it.
 
Here' s what I get:

When the first identity is shown, the second one should follow from the definition of a geostationarty orbit since those three angles do not change.i.e. their rates of change will be zero.

Am I on the right track?
 
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