A polar satellite orbits a planet over it's poles.

An East/West orbiter (I couldn't find the term for such satellites) may orbit anywhere from LEO up as high as GEO.

How does the launch process (for want of a better word) differ other than that the former launches southward, and the latter eastward? Is there a difference?

  • $\begingroup$ Are you referring to retrograde orbits? $\endgroup$ – TildalWave Aug 18 '13 at 22:05
  • $\begingroup$ Both retrograde, and regular. I didn't want to put 'East-West', and 'West-East' together up there (+: It could be confusing. $\endgroup$ – Everyone Aug 19 '13 at 2:20
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    $\begingroup$ Gotcha. So in essence non-inclined orbits and near-equatorial orbits, or putting it otherwise, box orbits whose ground track doesn't cross the north-south pole boundaries. I'm not sure there's a single name for them, short of saying "non-polar orbits". :| $\endgroup$ – TildalWave Aug 19 '13 at 2:41

The key difference is that you don't get any rotational assistance from the Earth for a North-South launch if you try a direct launch into orbit.

In practice this means North-South orbits seem to be launched at a relatively steep angle to the North or South while still getting some of the Earth's rotation boost and then using thrust when in orbit to change from a steep angle to a North-South orbit.

Haven't managed to find figures on optimum launch direction - will update as I find them.

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    $\begingroup$ Also, since you gain no advantage from the Earth's rotation, you can launch from pads at notherly latitudes, which is very convenient for countries far from the equator. $\endgroup$ – user6244 Oct 7 '14 at 18:49
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    $\begingroup$ @user6244 High latitudes (not just North, but also South). Then again, this is true for any latitudes, including equatorial. ;) $\endgroup$ – TildalWave Oct 7 '14 at 19:00
  • $\begingroup$ If your target orbit is polar, your equatorial rotation is a burden rather than a benefit - launching closer to the poles becomes the more efficient option for polar flights, since there is less influence from Earth's rotation that must be canceled. $\endgroup$ – Saiboogu Jan 23 '18 at 20:56

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