Talk:Geosynchronous orbit

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geosynchronous orbit != geostationary orbit

    a geostationary orbit must be:
           1. geosynchronous
           2. circular
           3. equatorial (zero inclination)

Science fiction writer and scientist Arthur C. Clarke wrote about this belt in 1945, hence the name. Clarke's and Herman Potočnik's visions of geostationary communications satellites were made a reality in 1962 with the launch of Telstar.

Hang on, this gives the wrong impression that Telstar was a geostationary satellite - it wasn't, the first one was Intelsat 1 in 1965. -- Arwel 09:46 Apr 15, 2003 (UTC)

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Removed: Free Body Diagram section/:insert diagram here/:insert Text or other math here.Mat-C 18:09, 30 Apr 2004 (UTC)

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The empty Free Body Diagram section still served a purpose in that it would be useful if it was not blank. Leaving it there may motivate someone to add a diagram, without it, it is far less likely. { MB | マイカル } 18:20, Apr 30, 2004 (UTC)

That is why it is here, "todo" lists don't belong in articles. What exactly is this diagram? I might be able to draw it.Mat-C 18:48, 30 Apr 2004 (UTC)

(I've saved my changed, but a bit more to do at some point)Mat-C 18:48, 30 Apr 2004 (UTC)

Free body diagram. I suggest you check out the free body diagram on page 2 of this pdf since it is esentially what we need mionus the whole tower thing. Although since I am not a physicist I can not be sure if this is all that is needed, it seems to me that this is a pretty sparse diagram. { MB | マイカル } 21:15, Apr 30, 2004 (UTC)

Here is another great place for inspiration.

• I removed Clarke's and Herman Poto&#269nik's visions of geostationary communications satellites were made a reality in 1962 with the launch of Telstar as it looks plain wrong to me (not a geo-synch orbit)
• I stated that "geostationary" can be applied to other non-earth bodies, feel free to separate that bit out of the first paragraph if thats not the case.Mat-C 18:51, 30 Apr 2004 (UTC)

I agree with moving a lot of the geostationary orbit stuff to that page, however I believe there may be a case for the Derivation of orbital period stuff to be here as well - it shows how to calculate the orbital period for all non-active circular geosync orbits. Only problem now is we have two geostationary links Mat-C 20:20, 1 May 2004 (UTC)

Are there uses for circular geosynchronous orbits that aren't geostationary, i.e. geosync orbits that are circular but not at the equator? If there is such a use then I agree that it would make sense to put your derivation here as well.

I previously considered merging geosynchronous orbit and geostationary orbit, but it seems like there is plenty to write about each separately. Wmahan. 20:41, 2004 May 1 (UTC)

The section on history of geosynchronous comm satellites indicated that they are no longer used for telephone communications. I edited this because it is no longer so - in fact, I am employed by a telephone company that must use satellites to reach over 35 of its communites, since there is no practical or affordable way to extend either fibre optic or microwave to those locations. Doubtless, places in Alaska and Greenland are in the same situation, and as Russia's telecom infrastructure improves, it will have to do the same. gcapp@praize.ca

Ships at sea also use satellite phones, so I added that. Would it be useful to link to Inmarsat?

Might it be useful to include a derivation of the height of geosynchronous orbits, and maybe also the height of the orbit in the case of the Earth? I've just had to do it for an essay and it's pretty easy. I've just started using Wikipedia though so I'm all fingers and thumbs with the equation writing system.--Kimonokraken 18:00, 23 April 2006 (UTC)

the size of the orbit is already there: "A circular geosynchronous orbit in the plane of the Earth's equator has a radius of approximately 42,164 km (from the centre of the Earth) or approximately 35,786 km (22,236 statute miles) above mean sea level."

The derivation is at Geostationary orbit#Derivation of geostationary altitude.

—wwoods 21:31, 23 April 2006 (UTC)

[edit] synchronous/sidereal period

what about an orbital period that has half the sidereal rotation period of the Earth so that it appears above the same spot exactly twice in one day or integer multiples of the rotation period. Couldn't these be considered geosynchronos orbits, after all they are synchronised with the earth rotation period? I don't know whether they're useful though...

The Molniya satellites are in 12-hour orbits. They're (roughly) over the same area every other orbit.

However, while the orbital period is intentionally a fraction of the Earth's rotational period, calling it "synchronous" is more likely to cause confusion than clarification.

—wwoods 17:39, 11 Apr 2005 (UTC)