AsteroidEpochElements Struct Reference

One snapshot of Keplerian orbital elements at a specific epoch, used by the extended asteroid ephemeris pack. More...

#include <MinorPlanet.hpp>

Data Fields
double	epochJDE
	JDE epoch of these elements.
double	pericenterDistance
	AU.
double	eccentricity
double	inclination
	radians
double	ascendingNode
	radians
double	argOfPericenter
	radians
double	meanAnomalyAtEpoch
	radians at epochJDE (replaces timeAtPericenter)
double	meanMotion
	radians/day

Detailed Description

One snapshot of Keplerian orbital elements at a specific epoch, used by the extended asteroid ephemeris pack.

Angles are in radians, distances in AU, time in JDE.

meanAnomalyAtEpoch is stored instead of timeAtPericenter (Tp) because Tp from JPL Horizons always refers to the nearest perihelion to the query date and is therefore not a stable value to store per-epoch. We derive the equivalent t0 on demand as: t0 = epochJDE - meanAnomalyAtEpoch / meanMotion

Field Documentation

argOfPericenter

double AsteroidEpochElements::argOfPericenter

radians

ascendingNode

double AsteroidEpochElements::ascendingNode

radians

eccentricity

double AsteroidEpochElements::eccentricity

epochJDE

double AsteroidEpochElements::epochJDE

JDE epoch of these elements.

inclination

double AsteroidEpochElements::inclination

radians

meanAnomalyAtEpoch

double AsteroidEpochElements::meanAnomalyAtEpoch

radians at epochJDE (replaces timeAtPericenter)

meanMotion

double AsteroidEpochElements::meanMotion

radians/day

pericenterDistance

double AsteroidEpochElements::pericenterDistance

AU.