Astro with some minor changes to placate Unix.

src/cmd/astro/merc.c

@@ -0,0 +1,84 @@
+#include "astro.h"
+
+void
+merc(void)
+{
+	double pturbl, pturbr;
+	double lograd;
+	double dele, enom, vnom, nd, sl;
+	double q0, v0, t0, j0 , s0;
+	double lsun, elong, ci, dlong;
+
+	ecc = .20561421 + .00002046*capt - 0.03e-6*capt2;
+	incl = 7.0028806 + .0018608*capt - 18.3e-6*capt2;
+	node = 47.145944 + 1.185208*capt + .0001739*capt2;
+	argp = 75.899697 + 1.555490*capt + .0002947*capt2;
+	mrad = .3870986;
+	anom = 102.279381 + 4.0923344364*eday + 6.7e-6*capt2;
+	motion = 4.0923770233;
+
+	q0 = 102.28  + 4.092334429*eday;
+	v0 = 212.536 + 1.602126105*eday;
+	t0 = -1.45  + .985604737*eday;
+	j0 = 225.36 + .083086735*eday;
+	s0 = 175.68 + .033455441*eday;
+
+	q0 *= radian;
+	v0 *= radian;
+	t0 *= radian;
+	j0 *= radian;
+	s0 *= radian;
+
+	incl *= radian;
+	node *= radian;
+	argp *= radian;
+	anom = fmod(anom, 360.)*radian;
+
+
+	enom = anom + ecc*sin(anom);
+	do {
+		dele = (anom - enom + ecc * sin(enom)) /
+			(1. - ecc*cos(enom));
+		enom += dele;
+	} while(fabs(dele) > converge);
+	vnom = 2.*atan2(sqrt((1.+ecc)/(1.-ecc))*sin(enom/2.),
+			cos(enom/2.));
+	rad = mrad*(1. - ecc*cos(enom));
+
+	icosadd(mercfp, merccp);
+	pturbl =  cosadd(2, q0, -v0);
+	pturbl += cosadd(2, q0, -t0);
+	pturbl += cosadd(2, q0, -j0);
+	pturbl += cosadd(2, q0, -s0);
+
+	pturbr =  cosadd(2, q0, -v0);
+	pturbr += cosadd(2, q0, -t0);
+	pturbr += cosadd(2, q0, -j0);
+
+/*
+ *	reduce to the ecliptic
+ */
+
+	lambda = vnom + argp + pturbl*radsec;
+	nd = lambda - node;
+	lambda = node + atan2(sin(nd)*cos(incl), cos(nd));
+
+	sl = sin(incl)*sin(nd);
+	beta = atan2(sl, pyth(sl));
+
+	lograd = pturbr*2.30258509;
+	rad *= 1. + lograd;
+
+	motion *= radian*mrad*mrad/(rad*rad);
+	semi = 3.34;
+
+	lsun = 99.696678 + 0.9856473354*eday;
+	lsun *= radian;
+	elong = lambda - lsun;
+	ci = (rad - cos(elong))/sqrt(1. + rad*rad - 2.*rad*cos(elong));
+	dlong = atan2(pyth(ci), ci)/radian;
+	mag = -.003 + .01815*dlong + .0001023*dlong*dlong;
+
+	helio();
+	geo();
+}