Orbits (1 Viewer)

[water89]

Question from Neap I couldnt really answer.

3. Briefly explain why a Geostationary Satellite couldnt be place above Sydney?


This what ive been thinking:

Well if the Satellite was placed perpendicular to the equatorial plane (hence becoming a polar orbit) then as the Earth moves relative to it then the orbit would shift to the West and hence wouldnt be a Geostationary Satellite (remains at a fixed point above the Earth).

I looked at some materials and it said that if a satellite with the same period as a geostationary satellite is placed anywhere else either then above the equator then ITS ORBIT WOULD TRACE OUT A FIGURE 8 SHAPE (what the hell) and hence it would only be a geosynchrous satellite.

PLease anyone who knows the answer help me out/ explain to me what the hell the figure 8 shape means.

 

[shady145]

maybe the figure 8 was the name of a picture on the website lol
it cannot be a geostat as it is not on the equator.
geostat satelites are those only around the equator with the approx radius of 42800km

 

[4theHSC]

Ok, I'm not terribly sure, but i think what you are saying makes some sense... Geostationary satellites are made so that they are on top of the equator... and so their period would be 24hrs around the earth (earth's rotation)... so Sydney being in the southern hemisphere, no geostationary satellite can be put there as 1) they are far away from the equator, 2) The period of Geostationary satellites would change and so they will not be called geostationary satellites...

Geosynchronous are the same as Geostationary except that they are not bound by the equator and usually trace out an 8 shape... but then again, this is just my answer... I don't think its completely right.

 

[kaz1]

Sydney is not on the equator.

 

[water89]

Thank you Kaz, very insightful hahahah.

 

[Nuendo]

Geosynchronous are the same as Geostationary except that they are not bound by the equator and usually trace out an 8 shape... but then again, this is just my answer... I don't think its completely right.

you are correct. if a satellite with an altitude of approx 35,800 km isn't above the equator, it won't remain at a fixed point. if we were trace it's location from earth, we would see a 'figure 8' pattern, which has a period equal to that of the earth's - hence, geosynchronous

 

[darkchild69]

Yep, just what everyone else has said.

Geostationary orbits are along the equatorial plane. Sydney does not lie on the equatorial plane, so a satellite placed at the same altitude as a Geostationary satellite would not appear stationary.
It would appear to be geosynchronous, which basically means, at the same time each day the satellite would appear at the same point. I'm pretty sure geosynchronous satellites have been taken out of the syllabus, but i still teach it anyway