You can also use Hugin (my tool of choice for this)

Here is a mini-tut....

Load up your equirectangular image into hugin selecting equirectangular and a 360 degree horizontal field of view:
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In the Images Tab select the image and change its pitch to 90:
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Click the preview icon (little map with the crosshairs in the top row of icons) to verify the view (It will be an equirectangular projection with the pitched image):
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On the Stitcher tab select orthographic progection (to get a "globe from space" view):
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And the result:
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-Rob A>