#ifndef _CONSTANTS_H
#define _CONSTANTS_H
/*
 *  Astronomical constants
 */
#define epoch       2444238.5      /* 1980 January 0.0 */

/*
 *  Constants defining the Sun's apparent orbit  
 */
#define elonge      278.833540     /* Ecliptic longitude of the Sun at epoch 1980.0 */
#define elongp      282.596403     /* Ecliptic longitude of the Sun at perigee */
#define eccent      0.016718       /* Eccentricity of Earth's orbit */
#define sunsmax     1.495985e8     /* Semi-major axis of Earth's orbit, km */
#define one_au      1.49597870691e8/* mean distance between the Earth and the Sun */
                                   /* dvh: sunsmax is not the maximum distance */
#define sunangsiz   0.533128       /* Sun's angular size, degs, at semi-major axis distance */

/*
 *  Elements of the Moon's orbit, epoch 1980.0
 */
#define mmlong      64.975464      /* Moon's mean lonigitude at the epoch */
#define mmlongp     349.383063     /* Mean longitude of the perigee at the epoch */
#define mlnode      151.950429     /* Mean longitude of the node at the epoch */
#define minc        5.145396       /* Inclination of the Moon's orbit */
#define mecc        0.054900       /* Eccentricity of the Moon's orbit */
#define mangsiz     0.5181         /* Moon's angular size at distance a from Earth */
#define msmax       384401.0       /* Semi-major axis of Moon's orbit in km */
#define mparallax   0.9507         /* Parallax at distance a from Earth */
#define synmonth    29.53058868    /* Synodic month (new Moon to new Moon) */
#define lunatbase   2423436.0      /* Base date for E. W. Brown's numbered series of lunations (1923 January 16) */

/*
 *  Properties of the Earth
 */
#define earthrad    6378.16        /* Radius of Earth in kilometres */

#endif