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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?

Everyone
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1 Answers1

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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.

Rory Alsop
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    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. –  Oct 07 '14 at 18:49
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    @user6244 High latitudes (not just North, but also South). Then again, this is true for any latitudes, including equatorial. ;) – TildalWave Oct 07 '14 at 19:00
  • 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. – Saiboogu Jan 23 '18 at 20:56