Anybody can answer my query ?
They don't have to be circular. They can have as much eccentricity as you want, as long as their period is 24 hours.beserk said:Anybody can answer my query ?
russ_watters said:Well, what I was getting at is if the orbits weren't circular, they wouldn't be stationary.
Could be...like me!Janus said:True, but the OP wasn't asking about geostationary orbits, but geosynchronous orbits. The first has to be circular and in the equatorial plane, the second doesn't. Of course, it is possible that the OP isn't aware of the difference or said one when he meant the other.
Janus said:True, but the OP wasn't asking about geostationary orbits, but geosynchronous orbits. The first has to be circular and in the equatorial plane, the second doesn't. Of course, it is possible that the OP isn't aware of the difference or said one when he meant the other.
Isn't a geostationary orbit a special case of a geosynchronous orbit. The wording of the article suggests not.A geosynchronous orbit is one that has the same orbital period as the Earth's sidereal rotation (23 h 56 m 4 sec), but does not have an orbital inclination and eccentricity of zero. A satellite in such an orbit would weave figure-eights around a point on the ecliptic when viewed from the ground. It is often used to mean geostationary orbit and is sometimes also called a Clarke orbit.
A geosynchronous orbit is a geocentric orbit that has the same orbital period as the sidereal rotation period of the Earth. It has a semi-major axis of 42,164 km .
Synchronous orbits exist around all moons, planets, stars and black holes —unless they rotate so slowly that the orbit would be outside their Hill sphere. Most inner moons of planets have synchronous rotation, so their synchronous orbits are, in practice, limited to their leading and trailing Lagrange points. Objects with chaotic rotations (such as Hyperion) are also problematic, as their synchronous orbits keep changing unpredictably.
If a geosynchronous orbit is circular and equatorial then it is also a geostationary orbit, and will maintain the same position relative to the Earth's surface.
Geostationary orbits are a special case of geosynchronous orbits, just as a square is a special case of rectangles, and a circle is a special case of ellipses. (Wow, notice how I managed to come full circle? )russ_watters said:Could be...like me!
Is there much use for geosynchronous orbits as oposed to geostationary? Ie, are there applications where a little bit of back-and-forth doesn't make much difference?