Source Code
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These source-code files were obtained by digitally photographing
an Artemis 72 program listing from a private collection and then
modifying pre-existing Comanche 55 (Apollo 11) source files to
incorporate changes. Note that the page images
presented online are of reduced quality, and that additional images
may be available. Report any conversion errors or legibility
problems in page images to info@sandroid.org.
Notations on the program listing read, in part:GAP: ASSEMBLE REVISION 072 OF AGC PROGRAM ARTEMIS BY NASA 2021114-011 11:40 FEB. 26, 1971 THIS AGC PROGRAM SHALL ALSO BE REFERRED TO AS COLOSSUS 3 THIS PROGRAM IS INTENDED FOR USE IN THE CM AS SPECIFIED IN REPORT R-577. THIS PROGRAM WAS PREPARED UNDER OSR PROJECT 55-23890, SPONSORED BY THE MANNED SPACECRAFT CENTER OF THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION THROUGH CONTRACT NAS 9-4065 WITH THE CHARLES STARK DRAPER LABORATORY, MASSACHUSETTS INSTITUTE OF TECHNOLOGY, CAMBRIDGE, MASS. |
034979,000002: # Copyright: Public domain.
034980,000003: # Filename: LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc
034981,000004: # Purpose: Part of the source code for Artemis (i.e., Colossus 3),
034982,000005: # build 072. This is for the Command Module's (CM)
034983,000006: # Apollo Guidance Computer (AGC), we believe for
034984,000007: # Apollo 15-17.
034985,000008: # Assembler: yaYUL
034986,000009: # Contact: Jim Lawton <jim DOT lawton AT gmail DOT com>
034987,000010: # Website: www.ibiblio.org/apollo/index.html
034988,000011: # Page scans: www.ibiblio.org/apollo/ScansForConversion/Artemis072/
034989,000012: # Mod history: 2009-08-11 JL Adapted from corresponding Comanche 055 file.
034990,000013: # 2010-02-20 RSB Un-##'d this header.
034991,000014:
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Page 789 |
034993,000016:
034994,000017: # LUNAR AND SOLAR EPHEMERIDES SUBROUTINES
034995,000018:
034996,000019: # FUNCTIONAL DESCRIPTION
034997,000020:
034998,000021: # THESE SUBROUTINES ARE USED TO DETERMINE THE POSITION AND VELOCITY
034999,000022: # VECTORS OF THE SUN AND THE MOON RELATIVE TO THE EARTH AT THE
035000,000023: # SPECIFIED GROUND ELAPSED TIME INPUT BY THE USER.
035001,000024:
035002,000025: # THE POSITION OF THE MOON IS STORED IN THE COMPUTER IN THE FORM OF
035003,000026: # A NINTH DEGREE POLYNOMIAL APPROXIMATION WHICH IS VALID OVER A 15
035004,000027: # DAY INTERVAL BEGINNING SHORTLY BEFORE LAUNCH. THEREFORE THE TIME
035005,000028: # INPUT BY THE USER SHOULD FALL WITHIN THIS 15 DAY INTERVAL.
035006,000029: #
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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. |
035014,000037:
035015,000038: # LSPOS COMPUTES THE POSITION VECTORS OF THE SUN AND THE MOON.
035016,000039:
035017,000040: # LUNPOS COMPUTES THE POSITION VECTOR OF THE MOON.
035018,000041:
035019,000042: # LUNVEL COMPUTES THE VELOCITY VECTOR OF THE MOON.
035020,000043:
035021,000044: # CALLING SEQUENCE
035022,000045:
035023,000046: # DLOAD CALL
035024,000047: # TIME GROUND ELAPSED TIME
035025,000048: # SUBROUTINE LSPOS OR LUNPOS OR LUNVEL
035026,000049:
035027,000050: # INPUT
035028,000051:
035029,000052: # 1) SPECIFIED GROUND ELAPSED TIME IN CS x B-28 LOADED IN MPAC.
035030,000053:
035031,000054: # 2) TIMEMO - TIME AT THE CENTER OF THE RANGE OVER WHICH THE LUNAR
035032,000055: # POSITION POLYNOMIAL IS VALID IN CS x B-42.
035033,000056:
035034,000057: # 3) VECOEM - VECTOR COEFFICIENTS OF THE LUNAR POSITION POLYNOMIAL
035035,000058: # LOADED IN DESCENDING SEQUENCE IN METERS/CS**N x B-2
035036,000059:
035037,000060: # 4) RESO - POSITION VECTOR OF THE SUN RELATIVE TO THE EARTH AT
035038,000061: # TIMEMO IN METERS x B-38
035039,000062:
035040,000063: # 5) VESO - VELOCITY VECTOR OF THE SUN RELATIVE TO THE EARTH AT
035041,000064: # TIMEMO IN METERS/CS x B-9
035042,000065: #
035043,000066: # 6) OMEGAES - ANGULAR VELOCITY OF THE VECTOR RESO AT TIMEMO IN
035044,000067: # REV/CS x B+26.
035045,000068:
035046,000069: # ALL EXCEPT THE FIRST INPUT ARE INCLUDED IN THE PRE-LAUNCH
035047,000070: # ERASABLE DATA LOAD.
035048,000071:
035049,000072: # OUTPUT - LSPOS
035050,000073:
035051,000074: # 1) 2D OF VAC AREA CONTAINS THE POSITION VECTOR OF THE SUN RELATIVE
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Page 790 |
035053,000076: # TO THE EARTH AT TIME INPUT BY THE USER IN METERS x B-38.
035054,000077:
035055,000078: # 2) MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
035056,000079: # EARTH AT TIME INPUT BY THE USER IN METERS x B-29.
035057,000080:
035058,000081: # OUTPUT - LUNPOS
035059,000082:
035060,000083: # MPAC CONTAINS THE POSITION VECTOR OF THE MOON RELATIVE TO THE
035061,000084: # EARTH AT THE TIME INPUT BY USER IN METERS x B-29.
035062,000085:
035063,000086: # OUTPUT - LUNVEL
035064,000087:
035065,000088: # MPAC CONTAINS THE VELOCITY VECTOR OF THE MOON RELATIVE TO THE
035066,000089: # EARTH AT THE TIME INPUT BY THE USER IN METERS/CS x B-7.
035067,000090:
035068,000091: # SUBROUTINES USED
035069,000092:
035070,000093: # NONE
035071,000094:
035072,000095: # REMARKS
035073,000096:
035074,000097: # THE VAC AREA IS USED FOR STORAGE OF INTERMEDIATE AND FINAL RESULTS
035075,000098: # OF COMPUTATIONS.
035076,000099:
035077,000100: # S1, X1, AND X2 ARE USED BY THESE SUBROUTINES.
035078,000101: # PRELAUNCH ERASABLE DATA LOAD ARE ONLY ERASABLE STORAGE USED BY
035079,000102: # THESE SUBROUTINES.
035080,000103: # RESTARTS DURING OPERATION OF THESE SUBROUTINES MUST BE HANDLED BY
035081,000104: # THE USER.
035082,000105:
035083,000106: 26,2000 SETLOC EPHEM
035084,000107: 26,2000 BANK
035085,000108:
035086,000109: 26,2136 COUNT* $$/EPHEM
035087,000110: 26,2136 E7,1777 EBANK= WHOCARES
035088,000111: 26,2136 52170 LSPOS AXT,1 GOTO
035089,000112: 26,2137 54163 RES # AREA. THE POSITION VECTOR OF THE MOON
035090,000113: 26,2140 54146 LSTIME # IS STORED IN MPAC.
035091,000114: 26,2141 52170 LUNPOS AXT,1 GOTO # COMPUTES THE POSITION VECTOR OF THE MOON
035092,000115: 26,2142 54201 REM # AND STORES IT IN MPAC.
035093,000116: 26,2143 54146 LSTIME
035094,000117: 26,2144 77770 LUNVEL AXT,1
035095,000118: 26,2145 54212 VEM # AND STORES IT IN MPAC.
035096,000119: 26,2146 54201 LSTIME SETPD SR
035097,000120: 26,2147 00001 0D
035098,000121: 26,2150 20617 14D
035099,000122: 26,2151 57571 TAD DCOMP
035100,000123: 26,2152 01707 TEPHEM
035101,000124: 26,2153 57571 TAD DCOMP
035102,000125: 26,2154 02034 TIMEMO
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035104,000127: 26,2155 66261 SL SSP
035105,000128: 26,2156 20221 16D
035106,000129: 26,2157 00051 S1
035107,000130: 26,2160 00006 6D
035108,000131: 26,2161 77650 GOTO
035109,000132: 26,2162 00046 X1
035110,000133: 26,2163 41206 RES PUSH DMP # PD- 2
035111,000134: 26,2164 02147 OMEGAES
035112,000135: 26,2165 71406 PUSH COS # PD- 4
035113,000136: 26,2166 65361 VXSC PDDL # PD- 8
035114,000137: 26,2167 02133 RESO
035115,000138: 26,2170 63356 SIN PDVL # PD-10
035116,000139: 26,2171 02133 RESO
035117,000140: 26,2172 53406 PUSH UNIT # PD-16
035118,000141: 26,2173 53435 VXV UNIT
035119,000142: 26,2174 02141 VESO
035120,000143: 26,2175 76435 VXV VSL1 # PD-10
035121,000144: 26,2176 53361 VXSC VAD # PD-02
035122,000145: 26,2177 77772 VSL1
035123,000146: 26,2200 14003 RESA STODL 2D # RES IN METERS x B-38 IN 2D OF VAC. PD- 0
035124,000147: 26,2201 63370 REM AXT,1 PDVL # PD- 2
035125,000148: 26,2202 00066 54D
035126,000149: 26,2203 02037 VECOEM
035127,000150: 26,2204 52761 REMA VXSC VAD*
035128,000151: 26,2205 00001 0D
035129,000152: 26,2206 02133 VECOEM +60D,1
035130,000153: 26,2207 72500 TIX,1 VSL2 # REM IN METERS x B-29 IN MPAC.
035131,000154: 26,2210 54204 REMA
035132,000155: 26,2211 77616 RVQ
035133,000156: 26,2212 65370 VEM AXT,1 PDDL # PD- 2
035134,000157: 26,2213 00060 48D
035135,000158: 26,2214 14233 NINEB4
035136,000159: 26,2215 74206 PUSH VXSC # PD- 4
035137,000160: 26,2216 02037 VECOEM
035138,000161: 26,2217 77761 VEMA VXSC
035139,000162: 26,2220 00001 0D
035140,000163: 26,2221 14005 STODL 4D # PD- 2
035141,000164: 26,2222 41425 DSU PUSH # PD- 4
035142,000165: 26,2223 31771 ONEB4
035143,000166: 26,2224 53357 VXSC* VAD
035144,000167: 26,2225 02125 VECOEM +54D,1
035145,000168: 26,2226 00005 4D
035146,000169: 26,2227 72500 TIX,1 VSL2 # VEM IN METERS/CS x B-7 IN MPAC.
035147,000170: 26,2230 54217 VEMA
035148,000171: 26,2231 77616 RVQ
035149,000172: 26,2232 22000 00000 NINEB4 2DEC 9.0 B-4
035150,000173: 26,2234 34,3770 ONEB4 EQUALS DP2(-4) # 1 B-4
035151,000174:
End of include-file LUNAR_AND_SOLAR_EPHEMERIDES_SUBROUTINES.agc. Parent file is MAIN.agc