I am trying to find the eccentricity of a planet in order to be able to calculate perihelion and aphelion distances. I can get a lot of the equation, but am having issues with the angular momentum, and the coefficient of the inverse-square law central force such as gravity or electrostatics in classical physics; that second one especially leaves me confused.
The characteristics are 3.296×1024 Kg, orbital period of 34713964.7399 seconds, rotation period of 69480 Seconds. Semi-major axis is 159425506264.96738 metres if I calculated that part correctly.
Assume the sun is the same as ours for simplicities sake. The star is supposed to be somewhat bigger, but comparable. I just need the sun as a assumption to make an upper/lower bound.
So what would the eccentricity be for this? And thank you for your time, if you choose to help. I apologize for this if it is a bother.