I am trying to write a simple java program to model the motion of planets according to kepler's second law. I have everything working...except I can't find how to find an equation relating position and time. I have(adsbygoogle = window.adsbygoogle || []).push({});

x = a cos(t)

y = b sin(t)

where a and b are the semimajor and semiminor axises respectively, but those equations are for uniform velocity which planets do not exhibit. I've googled around and looked in a few books but I can not find any such equation. I can find the equation for velocity...but I need a model for the actual position. Does anyone know of any such model or have any suggestions?

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# Modeling eliptical motion of planets

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