orrery::initial_conditions::KeplerParameters Struct Reference

A bound two-body orbit, described by its elements. More...

#include <orrery/initial_conditions/kepler.hpp>

Public Attributes
core::Real	primary_mass = 1
core::Real	secondary_mass = 1
core::Real	semi_major_axis = 1
	The semi-major axis of the relative orbit, that is, of the separation between the two bodies rather than of either body's path about the centre of mass.
core::Real	eccentricity = 0
	Zero for a circle, approaching one for an orbit that grazes the centre.

Detailed Description

A bound two-body orbit, described by its elements.

Only the elements that affect the scalars this project measures are included. Inclination, the argument of periapsis and the longitude of the ascending node orient the orbit in space without changing its period, energy or the magnitude of its angular momentum, so they would add three parameters that no test could distinguish. The orbit is placed in the x-y plane with periapsis along the positive x axis.

Member Data Documentation

eccentricity

core::Real orrery::initial_conditions::KeplerParameters::eccentricity = 0

Zero for a circle, approaching one for an orbit that grazes the centre.

Values at or above one describe a parabolic or hyperbolic encounter. Those are unbound, have no period, and their energy is not negative, so every function here would be answering a question about an ellipse that does not exist; the generator rejects them rather than returning something shaped like an answer.

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The documentation for this struct was generated from the following file:

• orrery/initial_conditions/kepler.hpp