plan9port

fork of plan9port with libvec, libstr and libsdb
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sun.c (2267B)


      1 #include "astro.h"
      2 
      3 void
      4 sun(void)
      5 {
      6 	double mven, merth, mmars, mjup, msat;
      7 	double dmoon, mmoon, gmoon;
      8 	double pturbb, pturbl, pturbr, lograd;
      9 
     10 	ecc = .01675104 - 4.180e-5 * capt - 1.26e-7*capt2;
     11 	incl = 0;
     12 	node = 0;
     13 	argp = 281.220833 + .0000470684*eday + .000453*capt2
     14 		 + .000003*capt3;
     15 	mrad = 1;
     16 	anom = 358.475845 + .9856002670*eday - .000150*capt2
     17 		 - .000003*capt3;
     18 	motion = .9856473354;
     19 
     20 	dmoon = 350.737681+12.1907491914*eday-.001436*capt2;
     21 	gmoon = 11.250889 + 13.2293504490*eday - .003212*capt2;
     22 	mmoon = 296.104608 + 13.0649924465*eday + 9.192e-3*capt2;
     23 	mven  = 212.448 + 1.602121635*eday;
     24 	merth = 358.476 + 0.985600267*eday;
     25 	mmars = 319.590 + .524024095*eday;
     26 	mjup = 225.269 + .083082362*eday;
     27 	msat  = 175.593 + .033450794*eday;
     28 
     29 	dmoon = fmod(dmoon, 360.)*radian;
     30 	gmoon = fmod(gmoon, 360.)*radian;
     31 	mmoon = fmod(mmoon, 360.)*radian;
     32 	mven  *= radian;
     33 	merth *= radian;
     34 	mmars *= radian;
     35 	mjup *= radian;
     36 	msat  *= radian;
     37 
     38 	icosadd(sunfp, suncp);
     39 	anom += cosadd(4, mmars, merth, mven, mjup)/3600.;
     40 	anom += sinadd(5, mmars, merth, mven, mjup, .07884*capt)/3600.;
     41 
     42 	incl *= radian;
     43 	node *= radian;
     44 	argp *= radian;
     45 	anom = fmod(anom, 360.)*radian;
     46 
     47 /*
     48  *	computation of elliptic orbit
     49  */
     50 
     51 	lambda = anom + argp;
     52 
     53 	pturbl = (6910.057 - 17.240*capt - 0.052*capt2)*sin(anom)
     54 		 + (72.338 - 0.361*capt) * sin(2.*anom)
     55 		 + (1.054 - 0.001*capt) * sin(3.*anom)
     56 		 + 0.018 * sin(4.*anom);
     57 
     58 	lambda += pturbl*radsec;
     59 
     60 	beta = 0.;
     61 
     62 	lograd = (30.57e-6 - 0.15e-6*capt)
     63 		 - (7274.12e-6 - 18.14e-6*capt - 0.05e-6*capt2)*cos(anom)
     64 		 - (91.38e-6 - 0.46e-6*capt) * cos(2.*anom)
     65 		 - (1.45e-6 - 0.01e-6*capt) * cos(3.*anom)
     66 		 - 0.02e-6 * cos(4.*anom);
     67 
     68 	pturbl = cosadd(5, mmars, merth, mven, mjup, msat);
     69 	pturbl += sinadd(3, dmoon, mmoon, merth) + .9;
     70 	pturbl *= radsec;
     71 
     72 	pturbb =  cosadd(3, merth, mven, mjup);
     73 	pturbb += sinadd(3, gmoon, mmoon, dmoon);
     74 	pturbb *= radsec;
     75 
     76 	pturbr =  cosadd(5, mmars, merth, mven, mjup, msat);
     77 	pturbr += cosadd(3, dmoon, mmoon, merth);
     78 
     79 	lambda += pturbl;
     80 	if(lambda > pipi)
     81 		lambda -= pipi;
     82 
     83 	beta += pturbb;
     84 
     85 	lograd = (lograd+pturbr) * 2.30258509;
     86 	rad = 1 + lograd * (1 + lograd * (.5 + lograd/6));
     87 
     88 	motion *= radian*mrad*mrad/(rad*rad);
     89 
     90 	semi = 961.182;
     91 	if(flags['o'])
     92 		semi = 959.63;
     93 	mag = -26.5;
     94 }