Length of arc as independent argument for highly eccentric orbits (Q1199716)

Analytic step regulation for highly eccentric orbits may be achieved rather simply by choosing as independent argument the arc length \(s\) determined by an ordinary differential equation. In unperturbed motion the dependence of \(s\) on time \(t\) is expressed by means of elliptic functions. Equations of perturbed motion may prove very useful for numerically integrating highly eccentric orbits.