Path: SC/Ephem
% Simplified planet ephemerides from the almanac. Has functions for the orbital elements of the planets in the heliocentric frame. The elements are row vectors as follows: a = [ a1 a0] semi-major axis e = [ e1 e0] eccentricity i = [ i1 i0] inclination W = [ W1 W0] longitude of the ascending node w = [ w1 w0] argument of perigee L = [L2 L1 L0] mean longitude: L2 is revolutions per century where x = b1*T + b0 where T is Julian Centuries from J2000.0 and bi is a coefficient. Output of the angular quantities is either in degrees or radians. If one output is specified it will be a data structure containing the planet information. Type Planets for a demo. See SolarSys for computing planet locations. Since version 1. -------------------------------------------------------------------------- Form: Planets; % demo planetList = Planets; % list of planets [name, a, e, i, W, w, L, jDRef, mu, m, radius] = Planets( units, k ) d = Planets( units, k ) % output a data structure array -------------------------------------------------------------------------- ------ Inputs ------ units (1,3) Angular units ('deg' or 'rad') k (1,1) or {} Planet IDs, if not input get all nine; can be a cell array ------- Outputs ------- name (n,:) Name of planet a (n,2) Mean distance (au) e (n,2) Eccentricity i (n,2) Inclination wrt ecliptic plane (units) W (n,2) Longitude of ascending node wrt vernal equinox (units) w (n,2) Argument of perhelion (units) L (n,3) Mean longitude (units) jDRef (1,1) Reference Julian date mu (n,2) Gravitational parameter (km^3/s^2) m (n,1) Mass (kg) radius (n,1) Radius (km) - OR - d (:) Data structure array with above fields n is the number of planets -------------------------------------------------------------------------- References: Seidelmann, P. K., ed., Explanatory Supplement to the Astronomical Almanac, University Science Books, 1992. Table 5.8.1. p. 316. --------------------------------------------------------------------------
SC: Ephem/SolarSys
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