#ifndef PI
#define	PI		3.141592653589793
#endif

/* conversions among hours (of ra), degrees and radians. */
#define	degrad(x)	((x)*PI/180.)
#define	raddeg(x)	((x)*180./PI)
#define	hrdeg(x)	((x)*15.)
#define	deghr(x)	((x)/15.)
#define	hrrad(x)	degrad(hrdeg(x))
#define	radhr(x)	deghr(raddeg(x))

/* ratio of from synodic (solar) to sidereal (stellar) rate */
#define	SIDRATE		.9972695677

/* manifest names for planets.
 * N.B. must cooincide with usage in pelement.c and plans.c.
 */
#define	MERCURY	0
#define	VENUS	1
#define	MARS	2
#define	JUPITER	3
#define	SATURN	4
#define	URANUS	5
#define	NEPTUNE	6
#define	PLUTO	7