Hi all, I've got some conceptual questions that I need to clear before my exam I hope someone can help me out here. I understand that a geostationary satellite must orbit in the plane including the earth's centre, in order to stay above a particular surface of the earth. However, can a satellite orbit in vertical circles (sorry I can't find a better term for this) i.e, from north pole all the way down to the south and back up to the north pole again? There is no mention of any satellites that does this in my book and it seems that they always put emphasis on the need for them to orbit in the plane including the earth's centre. Thus, can it also orbit, anywhere else around the earth? Does anyone have the mathematical relation on g and the centripetal force at the equator of the earth? I was told that the centripetal force is less at the equator, since it must provide for the g? But I couldn't get a worked out mathematical formula for this, say compared to at the poles. mv^2/r = Gmm/r^2. How does the g come in here? Thanks a lot everyone.