Two ships orbit a planet in opposite directions. Each time they pass each other who is younger?
Is the planet rotating ? If so, how are the orbits aligned wrt to the poles ?
The planet is not rotating.
Assuming the planet is in inertial frame, equal times elapse on the ships between meetings.
Doesn't special relativity predict time dilation between the two ships since there is a relative velocity between them?
No,; this a common misconception.
They may see each others clocks running differently, but the ageing, or elapsed time will be the same for both when they meet.
So then, when does and when does not relativity apply?
What do they see?
That is a difficult question to answer. I've worked out the time-dilation between radially separated observers here -
I'll try and do the sums for orbiting observers at some time. Watch this space.
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