Path: Interplanetary/Ephemeris
% Get positions for an array of planets using the JPL ephemeris.
Gives the position vectors, gravitational parameters and velocity
for the planets. The frame is heliocentric and can be either in the Earth's
equatorial plane (default) or the ecliptic plane.
Modeled after PlanetPosition.
0. Sun (at origin)
1. Mercury
2. Venus
3. Earth
4. Mars
5. Jupiter
6. Saturn
7. Uranus
8. Neptune
9. Pluto
10. Geocentric Moon
11. Earth-Moon Barycenter
This calls the function InterpolateState which returns planet states in
the Earth equatorial frame and measured from the solar system barycenter.
If necessary, this loads the file lnxp1600p2200.405 into InterpolateState.
You must first initialize this function with a set of planet IDs and then
you can retrieve the states for a specific Julian date.
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Form:
PlanetPosJPL( 'initialize', id )
[r, mu, v] = PlanetPosJPL( 'update', jD, ecl )
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Inputs
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action (1,:) 'initialize' or 'update'
id or jD (1,n) Julian date (days) for update or planet ids
ecl (1,1) Flag for ecliptic plane (1), default is equatorial (0)
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Outputs
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r (3,n) Planetary position vectors
mu (1,n) Corresponding gravitational parameters
v (3,n) Velocity vectors
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SC: Ephem/CEcl2Eq SC: Ephem/InterpolateState Common: Time/Date2JD
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