Source Code
034835,000001: # Copyright: Public domain.
034836,000002: # Filename: LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc
034837,000003: # Purpose: Part of the source code for Comanche, build 055. It
034838,000004: # is part of the source code for the Command Module's
034839,000005: # (CM) Apollo Guidance Computer (AGC), Apollo 11.
034840,000006: # Assembler: yaYUL
034841,000007: # Reference: pp. 785-788
034842,000008: # Contact: Ron Burkey <info@sandroid.org>
034843,000009: # Website: http://www.ibiblio.org/apollo.
034844,000010: # Mod history: 2009-05-12 RSB Adapted from Colossus249 file of the same
034845,000011: # name and Comanche 055 page images.
034846,000012: # 2009-07-26 RSB Added annotations related to computation
034847,000013: # of the ephemeral(?) polynomials.
034848,000014:
034849,000015: # The contents of the "Comanche055" files, in general, are transcribed
034850,000016: # from scanned documents.
034851,000017:
034852,000018: # Assemble revision 055 of AGC program Comanche by NASA
034853,000019: # 2021113-051. April 1, 1969.
034854,000020:
034855,000021: # This AGC program shall also be referred to as Colossus 2A
034856,000022:
034857,000023: # Prepared by
034858,000024: # Massachusetts Institute of Technology
034859,000025: # 75 Cambridge Parkway
034860,000026: # Cambridge, Massachusetts
034861,000027:
034862,000028: # under NASA contract NAS 9-4065.
034863,000029:
034864,000030: # Refer directly to the online document mentioned above for further
034865,000031: # information. Please report any errors to info@sandroid.org.
034866,000032:
034867,000033: # Page 785
034868,000034: # LUNAR AND SOLAR EPHEMERIDES SUBROUTINES
034869,000035:
034870,000036: # FUNCTIONAL DESCRIPTION
034871,000037:
034872,000038: # THESE SUBROUTINES ARE USED TO DETERMINE THE POSITION AND VELOCITY
034873,000039: # VECTORS OF THE SUN AND THE MOON RELATIVE TO THE EARTH AT THE
034874,000040: # SPECIFIED GROUND ELAPSED TIME INPUT BY THE USER.
034875,000041:
034876,000042: # THE POSITION OF THE MOON IS STORED IN THE COMPUTER IN THE FORM OF
034877,000043: # A NINTH DEGREE POLYNOMIAL APPROXIMATION WHICH IS VALID OVER A 15
034878,000044: # DAY INTERVAL BEGINNING SHORTLY BEFORE LAUNCH. THEREFORE THE TIME
034879,000045: # INPUT BY THE USER SHOULD FALL WITHIN THIS 15 DAY INTERVAL.
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The 9th-degree polynomial spoken of here is a pad load, meaning that it is not actually hardcoded into the software. Additional information about calculating the polynomial can be found on the Orbiter NASSP wiki, as well as information about calculation of the solar ephemerides. |
034887,000053:
034888,000054: # LSPOS COMPUTES THE POSITION VECTORS OF THE SUN AND THE MOON.
034889,000055:
034890,000056: # LUNPOS COMPUTES THE POSITION VECTOR OF THE MOON.
034891,000057:
034892,000058: # LUNVEL COMPUTES THE VELOCITY VECTOR OF THE MOON.
034893,000059:
034894,000060: # SOLPOS COMPUTES THE POSITION VECTOR OF THE SUN.
034895,000061:
034896,000062: # CALLING SEQUENCE
034897,000063:
034898,000064: # DLOAD CALL
034899,000065: # TIME GROUND ELAPSED TIME
034900,000066: # SUBROUTINE LSPOS OR LUNPOS OR LUNVEL OR SOLPOS
034901,000067:
034902,000068: # INPUT
034903,000069:
034904,000070: # 1) SPECIFIED GROUND ELAPSED TIME IN CS x B-28 LOADED IN MPAC.
034905,000071:
034906,000072: # 2) TIMEMO -- TIME AT THE CENTER OF THE RANGE OVER WHICH THE LUNAR
034907,000073: # POSITION POLYNOMIAL IS VALID IN CS x B-42.
034908,000074:
034909,000075: # 3) VECOEM -- VECTOR COEFFICIENTS OF THE LUNAR POSITION POLYNOMIAL
034910,000076: # LOADED IN DESCENDING SEQUENCE IN METERS/CS**N x B-2
034911,000077:
034912,000078: # 4) RESO -- POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH AT
034913,000079: # TIMEMO IN METERS x B-38
034914,000080:
034915,000081: # 5) VESO -- VELOCITY VECTOR OF THE SUN RELATIVE TO THE EARTH AT
034916,000082: # TIMEMO IN METERS/CS x B-9
034917,000083: #
034918,000084: # 6) OMEGAES -- ANGULAR VELOCITY OF THE VECTOR RESO AT TIMEMO IN
034919,000085: # REV/CS x B+26
034920,000086:
034921,000087: # ALL EXCEPT THE FIRST INPUT ARE INCLUDED IN THE PRE-LAUNCH
034922,000088: # ERASABLE DATA LOAD.
034923,000089:
034924,000090: # OUTPUT -- LSPOS
034925,000091: # Page 786
034926,000092:
034927,000093: # 1) 2D OF VAC AREA CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE
034928,000094: # TO THE EARTH AT TIME INPUT BY THE USER IN METERS x B-38.
034929,000095:
034930,000096: # 2) MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
034931,000097: # EARTH AT TIME INPUT BY THE USER IN METERS x B-29
034932,000098:
034933,000099: # OUTPUT -- LUNPOS
034934,000100:
034935,000101: # MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
034936,000102: # EARTH AT THE TIME INPUT BY USER IN METERS x B-29
034937,000103:
034938,000104: # OUTPUT -- LUNVEL
034939,000105:
034940,000106: # MPAC CONTAINS THE VELOCITY VECTOR OF THE MOON RELATIVE TO THE
034941,000107: # EARTH AT THE TIME INPUT BY THE USER IN METERS/CS x B-7
034942,000108:
034943,000109: # OUTPUT -- SOLPOS
034944,000110:
034945,000111: # MPAC CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH
034946,000112: # AT TIME INPUT BY THE USER IN METERS x B-38.
034947,000113:
034948,000114: # SUBROUTINES USED
034949,000115:
034950,000116: # NONE
034951,000117:
034952,000118: # REMARKS
034953,000119:
034954,000120: # THE VAC AREA IS USED FOR STORAGE OF INTERMEDIATE AND FINAL RESULTS
034955,000121: # OF COMPUTATIONS.
034956,000122:
034957,000123: # S1, X1, AND X2 ARE USED BY THESE SUBROUTINES.
034958,000124:
034959,000125: # PRELAUNCH ERASABLE DATA LOAD ARE ONLY ERASABLE STORAGE USED BY
034960,000126: # THESE SUBROUTINES.
034961,000127:
034962,000128: # RESTARTS DURING OPERATION OF THESE SUBROUTINES MUST BE HANDLED BY
034963,000129: # THE USER.
034964,000130:
034965,000131: 36,2466 BANK 36
034966,000132: 26,2000 SETLOC EPHEM
034967,000133: 26,2000 BANK
034968,000134:
034969,000135: 26,2110 COUNT* $$/EPHEM
034970,000136: 26,2110 0003777 EBANK= END-E7
034971,000137: 26,2110 77774 LSPOS AXT,2 # COMPUTES POSITION VECTORS OF BOTH THE
034972,000138: 26,2111 54161 RESA # SUN AND THE MOON. THE POSITION VECTOR
034973,000139: 26,2112 52170 AXT,1 GOTO # OF THE SUN IS STORED IN 2D OF THE VAC
034974,000140: 26,2113 54143 RES # AREA. THE POSITION VECTOR OF THE MOON
034975,000141: 26,2114 54126 LSTIME # IS STORED IN MPAC.
034976,000142: 26,2115 52170 LUNPOS AXT,1 GOTO # COMPUTES THE POSITION VECTOR OF THE MOON
034977,000143: 26,2116 54162 REM # AND STORES IT IN MPAC.
034978,000144: 26,2117 54126 LSTIME
034979,000145: # Page 787
034980,000146: 26,2120 52170 LUNVEL AXT,1 GOTO # COMPUTES THE VELOCITY VECTOR OF THE MOON
034981,000147: 26,2121 54173 VEM # AND STORES IT IN MPAC.
034982,000148: 26,2122 54126 LSTIME
034983,000149: 26,2123 76020 SOLPOS STQ AXT,1 # COMPUTES THE POSITION VECTOR OF THE SUN
034984,000150: 26,2124 00047 X2 # AND STORES IT IN MPAC.
034985,000151: 26,2125 54143 RES
034986,000152: 26,2126 54201 LSTIME SETPD SR
034987,000153: 26,2127 00001 0D
034988,000154: 26,2130 20617 14D
034989,000155: 26,2131 57571 TAD DCOMP
034990,000156: 26,2132 01707 TEPHEM
034991,000157: 26,2133 57571 TAD DCOMP
034992,000158: 26,2134 02034 TIMEMO
034993,000159: 26,2135 66261 SL SSP
034994,000160: 26,2136 20221 16D
034995,000161: 26,2137 00051 S1
034996,000162: 26,2140 00006 6D
034997,000163: 26,2141 77650 GOTO
034998,000164: 26,2142 00046 X1
034999,000165: 26,2143 41206 RES PUSH DMP # PD- 2
035000,000166: 26,2144 02147 OMEGAES
035001,000167: 26,2145 71406 PUSH COS # PD- 4
035002,000168: 26,2146 65361 VXSC PDDL # PD- 8
035003,000169: 26,2147 02133 RESO
035004,000170: 26,2150 63356 SIN PDVL # PD-10
035005,000171: 26,2151 02133 RESO
035006,000172: 26,2152 53406 PUSH UNIT # PD-16
035007,000173: 26,2153 53435 VXV UNIT
035008,000174: 26,2154 02141 VESO
035009,000175: 26,2155 76435 VXV VSL1 # PD-10
035010,000176: 26,2156 53361 VXSC VAD # PD-02
035011,000177: 26,2157 52172 VSL1 GOTO # RES IN METERS x B-38 IN MPAC.
035012,000178: 26,2160 00047 X2
035013,000179: 26,2161 14003 RESA STODL 2D # RES IN METERS x B-38 IN 2D OF VAC. PD- 0
035014,000180: 26,2162 63370 REM AXT,1 PDVL # PD- 2
035015,000181: 26,2163 00066 54D
035016,000182: 26,2164 02037 VECOEM
035017,000183: 26,2165 52761 REMA VXSC VAD*
035018,000184: 26,2166 00001 0D
035019,000185: 26,2167 02133 VECOEM +60D,1
035020,000186: 26,2170 72500 TIX,1 VSL2 # REM IN METERS x B-29 IN MPAC.
035021,000187: 26,2171 54165 REMA
035022,000188: 26,2172 77616 RVQ
035023,000189: 26,2173 65370 VEM AXT,1 PDDL # PD- 2
035024,000190: 26,2174 00060 48D
035025,000191: 26,2175 14214 NINEB4
035026,000192: 26,2176 74206 PUSH VXSC # PD- 4
035027,000193: 26,2177 02037 VECOEM
035028,000194: 26,2200 77761 VEMA VXSC
035029,000195: 26,2201 00001 0D
035030,000196: # Page 788
035031,000197: 26,2202 14005 STODL 4D # PD- 2
035032,000198: 26,2203 41425 DSU PUSH # PD- 4
035033,000199: 26,2204 14216 ONEB4
035034,000200: 26,2205 53357 VXSC* VAD
035035,000201: 26,2206 02125 VECOEM +54D,1
035036,000202: 26,2207 00005 4D
035037,000203: 26,2210 72500 TIX,1 VSL2 # VEM IN METERS/CS x B-7 IN MPAC.
035038,000204: 26,2211 54200 VEMA
035039,000205: 26,2212 77616 RVQ
035040,000206: 26,2213 22000 00000 NINEB4 2DEC 9.0 B-4
035041,000207:
035042,000208: 26,2215 02000 00000 ONEB4 2DEC 1.0 B-4
035043,000209:
035044,000210:
035045,000211:
End of include-file LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc. Parent file is MAIN.agc