1. Make a composition that is twice as wide as it is tall. Try making the height twice the height of your finished video. Name this something like “map comp”.
2. Arrange all your photos within this comp. You might want to just do a few photos for a test, then go back and change the size of this comp if necessary.
3. Make a new comp that is the size of your finished video. Name it “main” or something.
4. Drag the “map comp” into the “main” comp.
5. Apply effect>perspective>CC sphere to the “map comp” layer.
6. Tweak the settings for the effect, maybe animate its rotation with keyframes.