I'm trying to understand how a free-transfer return works.

It makes sense to me conceptually, but putting numbers to it it is unclear.

I'm not sure how to obtain information about the transfer ellipse.

For example, with a Transfer Angle of 173.50 degrees and an Earth parking orbit of 195km, I cannot figure out the velocity of the spacecraft leaving Earth to reach the moon.

Normally I would get the Semi-Major Axis of the transfer ellipse (and from here calculate the velocities), but since this ellipse doesn't have an apoapsis at the Moon (i.e. the ellipse is larger), I don't know how to gain any additional information from this scenario.

Any help is appreciated. Thanks.



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