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What does the inclined circular ground track look like on a flat map projection of the Earth? The easiest way to see this is to think of a flat map as a globe printed on the label of a soda can. When the label is peeled off the can, the ground track for the inclined circular orbit turns an "S" shaped curved on a flat map of the Earth, as shown by the figure on the bottom right of the previous page. If you put the label back around the soda can, the "S" sure turns back into an inclined circular path that extends all the way around the globe. Notice that the "S" shaped ground track extends as far North as it does South. The maximum Northern and Southern latitudes on the ground tracks must equal the inclination of the orbit!
Also notice that if the Earth did not rotate, the ground track would span 360° of longitude (from 180°W to 180°E) along the Earth's surface and would always stay the same since the shuttle would pass over the same locations on the Earth, orbit after orbit (A shuttle launched from Cape Canaveral would pass back over Cape Canaveral once every orbit. As you will see in the next section, this does not happen because the Earth does indeed rotate beneath the shuttle).
The direction of the shuttle's motion along its orbit determines the direction of motion along the ground track. Since the shuttle orbits the Earth in a counterclockwise-direction, its path moves from left (West) to right (East) along the ground track (Note direction of arrow along the ground track).
The location of the shuttle's ground track on a map of the Earth is given by the longitude of the ascending and descending nodes. In this non-rotating Earth example, the ascending node (South to North equatorial crossing) occurs at the left edge of the map, the descending node (North to South equatorial crossing) in the middle, and another ascending node (of the next orbit) at the far right edge of the map. Notice that the two ascending nodes on the ground track mark the same location in the orbit. One convenient way to mark the beginning and end of an orbit on a ground track drawing is from ascending node to ascending node. In this example, for a non-rotating Earth, this orbit begins and ends over the same location on the Earth's surface because the left and right edges of the map mark and same longitude. This will not be true when we add in the effects of the Earth's rotation in the following section. 
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