EPOXI/EPOCh - Geometry for 27-28 March 2009 Earth North Polar Observation The EPOCh team provided the following observational geometry values covering the 27-28 March 2009 Earth North Polar Observation for convenience. Pointing telemetry in the form of reconstructed (actual) SPICE C-kernels was available for this period, and thus the data pipline was able to compute the corresponding parameters which are available in the archived data products. Table 1 - Reduced observational geometry parameters constructed by interpolating values in the raw look-up table (Table 2). Date & Time Julian CML Lat Range Helio S-O-SC Illum% ----------------------- -------------- ----- ----- ------- ------- ------ ------- 2009-03-27T16:19:42.327 2454918.180351 152.1 62.0 0.11414 0.99803 86.938 53.558 2009-03-27T16:34:43.404 2454918.190780 155.9 62.0 0.11414 0.99803 86.939 53.557 2009-03-27T16:49:36.989 2454918.201123 159.6 62.0 0.11415 0.99803 86.940 53.557 2009-03-27T17:04:43.433 2454918.211614 163.4 62.0 0.11415 0.99803 86.940 53.557 2009-03-27T17:19:41.109 2454918.222004 167.1 62.0 0.11415 0.99804 86.941 53.556 2009-03-27T17:34:43.377 2454918.232447 170.9 62.0 0.11415 0.99804 86.941 53.556 2009-03-27T17:49:36.888 2454918.242788 174.6 62.0 0.11415 0.99804 86.942 53.555 2009-03-27T18:04:43.406 2454918.253280 178.4 62.0 0.11415 0.99805 86.942 53.555 2009-03-27T18:19:41.027 2454918.263669 182.2 62.0 0.11415 0.99805 86.943 53.555 2009-03-27T18:34:43.331 2454918.274113 186.0 62.0 0.11415 0.99805 86.944 53.554 2009-03-27T18:49:36.849 2454918.284454 189.7 62.0 0.11415 0.99806 86.944 53.554 2009-03-27T19:04:43.360 2454918.294946 193.5 62.0 0.11415 0.99806 86.945 53.554 2009-03-27T19:19:40.993 2454918.305336 197.2 62.0 0.11415 0.99806 86.945 53.553 2009-03-27T19:34:43.296 2454918.315779 201.0 62.0 0.11415 0.99806 86.946 53.553 2009-03-27T19:49:36.814 2454918.326120 204.7 62.0 0.11415 0.99807 86.946 53.552 2009-03-27T20:04:43.181 2454918.336611 208.5 62.0 0.11415 0.99807 86.947 53.552 2009-03-27T20:19:40.946 2454918.347002 212.3 62.0 0.11415 0.99807 86.948 53.552 2009-03-27T20:34:43.214 2454918.357445 216.0 62.0 0.11415 0.99808 86.948 53.551 2009-03-27T20:49:36.772 2454918.367787 219.8 62.0 0.11416 0.99808 86.949 53.551 2009-03-27T21:04:43.154 2454918.378277 223.5 62.0 0.11416 0.99808 86.949 53.551 2009-03-27T21:19:40.900 2454918.388668 227.3 62.0 0.11416 0.99809 86.950 53.550 2009-03-27T21:34:43.184 2454918.399111 231.1 62.0 0.11416 0.99809 86.951 53.550 2009-03-27T21:49:36.722 2454918.409453 234.8 62.0 0.11416 0.99809 86.951 53.549 2009-03-27T22:04:43.112 2454918.419943 238.6 62.0 0.11416 0.99809 86.952 53.549 2009-03-27T22:19:40.861 2454918.430334 242.3 62.0 0.11416 0.99810 86.952 53.549 2009-03-27T22:34:43.141 2454918.440777 246.1 62.0 0.11416 0.99810 86.953 53.548 2009-03-27T22:49:36.687 2454918.451119 249.8 62.0 0.11416 0.99810 86.953 53.548 2009-03-27T23:04:43.073 2454918.461610 253.6 62.0 0.11416 0.99811 86.954 53.548 2009-03-27T23:19:40.835 2454918.472000 257.4 62.0 0.11416 0.99811 86.955 53.548 2009-03-27T23:34:43.009 2454918.482442 261.1 62.0 0.11416 0.99811 86.955 53.547 2009-03-27T23:49:36.641 2454918.492785 264.9 62.0 0.11416 0.99811 86.956 53.547 2009-03-28T00:04:43.038 2454918.503276 268.7 62.0 0.11416 0.99812 86.956 53.547 2009-03-28T00:19:40.800 2454918.513667 272.4 62.0 0.11416 0.99812 86.957 53.546 2009-03-28T00:34:42.970 2454918.524109 276.2 62.0 0.11416 0.99812 86.958 53.546 2009-03-28T00:49:36.614 2454918.534452 279.9 62.0 0.11416 0.99813 86.958 53.545 2009-03-28T01:04:43.000 2454918.544942 283.7 62.0 0.11416 0.99813 86.959 53.545 2009-03-28T01:19:40.668 2454918.555332 287.5 62.0 0.11417 0.99813 86.959 53.545 2009-03-28T01:34:42.936 2454918.565775 291.2 62.0 0.11417 0.99814 86.960 53.544 2009-03-28T01:49:36.454 2454918.576116 295.0 62.0 0.11417 0.99814 86.961 53.544 2009-03-28T02:04:42.965 2454918.586608 298.7 62.0 0.11417 0.99814 86.961 53.544 2009-03-28T02:19:40.633 2454918.596998 302.5 62.0 0.11417 0.99814 86.962 53.543 2009-03-28T02:34:42.909 2454918.607441 306.3 62.0 0.11417 0.99815 86.962 53.543 2009-03-28T02:49:36.416 2454918.617783 310.0 62.0 0.11417 0.99815 86.963 53.542 2009-03-28T03:04:42.938 2454918.628275 313.8 62.0 0.11417 0.99815 86.963 53.542 2009-03-28T03:19:40.551 2454918.638664 317.5 62.0 0.11417 0.99816 86.964 53.542 2009-03-28T03:34:42.862 2454918.649107 321.3 62.0 0.11417 0.99816 86.965 53.541 2009-03-28T03:49:36.389 2454918.659449 325.0 62.0 0.11417 0.99816 86.965 53.541 2009-03-28T04:04:42.798 2454918.669940 328.8 62.0 0.11417 0.99817 86.966 53.541 2009-03-28T04:19:40.525 2454918.680330 332.6 62.0 0.11417 0.99817 86.966 53.540 2009-03-28T04:34:42.828 2454918.690774 336.3 62.0 0.11417 0.99817 86.967 53.540 2009-03-28T04:49:36.319 2454918.701115 340.1 62.0 0.11417 0.99817 86.968 53.539 2009-03-28T05:04:42.713 2454918.711605 343.9 62.0 0.11417 0.99818 86.968 53.539 2009-03-28T05:19:40.467 2454918.721996 347.6 62.0 0.11417 0.99818 86.969 53.539 2009-03-28T05:34:42.742 2454918.732439 351.4 62.0 0.11417 0.99818 86.969 53.538 2009-03-28T05:49:36.280 2454918.742781 355.1 62.0 0.11417 0.99819 86.970 53.538 2009-03-28T06:04:42.678 2454918.753272 358.9 62.0 0.11417 0.99819 86.971 53.538 2009-03-28T06:19:40.440 2454918.763662 2.6 62.0 0.11418 0.99819 86.971 53.538 2009-03-28T06:34:42.708 2454918.774105 6.4 62.0 0.11418 0.99819 86.972 53.537 2009-03-28T06:49:36.246 2454918.784447 10.1 62.0 0.11418 0.99820 86.972 53.537 2009-03-28T07:04:42.643 2454918.794938 13.9 62.0 0.11418 0.99820 86.973 53.537 2009-03-28T07:19:40.393 2454918.805329 17.7 62.0 0.11418 0.99820 86.974 53.536 2009-03-28T07:34:42.575 2454918.815770 21.5 62.0 0.11418 0.99821 86.974 53.536 2009-03-28T07:49:36.219 2454918.826114 25.2 62.0 0.11418 0.99821 86.975 53.535 2009-03-28T08:04:42.605 2454918.836604 29.0 62.0 0.11418 0.99821 86.975 53.535 2009-03-28T08:19:40.359 2454918.846995 32.7 62.0 0.11418 0.99822 86.976 53.535 2009-03-28T08:34:42.541 2454918.857437 36.5 62.0 0.11418 0.99822 86.977 53.534 2009-03-28T08:49:36.106 2454918.867779 40.2 62.0 0.11418 0.99822 86.977 53.534 2009-03-28T09:04:42.570 2454918.878270 44.0 62.0 0.11418 0.99822 86.978 53.534 2009-03-28T09:19:40.234 2454918.888660 47.8 62.0 0.11418 0.99823 86.978 53.533 2009-03-28T09:34:42.502 2454918.899103 51.5 62.0 0.11418 0.99823 86.979 53.533 2009-03-28T09:49:36.024 2454918.909445 55.3 62.0 0.11418 0.99823 86.980 53.532 2009-03-28T10:04:42.532 2454918.919937 59.0 62.0 0.11418 0.99824 86.980 53.532 2009-03-28T10:19:40.207 2454918.930326 62.8 62.0 0.11418 0.99824 86.981 53.532 2009-03-28T10:34:42.467 2454918.940769 66.6 62.0 0.11418 0.99824 86.981 53.531 2009-03-28T10:49:35.990 2454918.951111 70.3 62.0 0.11418 0.99824 86.982 53.531 2009-03-28T11:04:42.497 2454918.961603 74.1 62.0 0.11418 0.99825 86.982 53.531 2009-03-28T11:19:40.169 2454918.971993 77.8 62.0 0.11418 0.99825 86.983 53.530 2009-03-28T11:34:42.440 2454918.982436 81.6 62.0 0.11418 0.99825 86.984 53.530 2009-03-28T11:49:35.947 2454918.992777 85.3 62.0 0.11418 0.99826 86.984 53.529 2009-03-28T12:04:42.365 2454919.003268 89.1 62.0 0.11418 0.99826 86.985 53.529 2009-03-28T12:19:40.079 2454919.013658 92.9 62.0 0.11418 0.99826 86.985 53.529 2009-03-28T12:34:42.394 2454919.024102 96.6 62.0 0.11419 0.99827 86.986 53.528 2009-03-28T12:49:35.885 2454919.034443 100.4 62.0 0.11419 0.99827 86.987 53.528 2009-03-28T13:04:42.330 2454919.044934 104.2 62.0 0.11419 0.99827 86.987 53.528 2009-03-28T13:19:40.037 2454919.055324 107.9 62.0 0.11419 0.99827 86.988 53.527 2009-03-28T13:34:42.359 2454919.065768 111.7 62.0 0.11419 0.99828 86.989 53.527 2009-03-28T13:49:35.851 2454919.076109 115.4 62.0 0.11419 0.99828 86.989 53.526 2009-03-28T14:04:42.244 2454919.086600 119.2 62.0 0.11419 0.99828 86.990 53.526 2009-03-28T14:19:40.006 2454919.096991 123.0 62.0 0.11419 0.99829 86.990 53.526 2009-03-28T14:34:42.274 2454919.107434 126.7 62.0 0.11419 0.99829 86.991 53.525 2009-03-28T14:49:35.812 2454919.117776 130.5 62.0 0.11419 0.99829 86.992 53.525 2009-03-28T15:04:42.210 2454919.128266 134.2 62.0 0.11419 0.99830 86.992 53.525 2009-03-28T15:19:39.964 2454919.138657 138.0 62.0 0.11419 0.99830 86.993 53.524 2009-03-28T15:34:42.146 2454919.149099 141.8 62.0 0.11419 0.99830 86.993 53.524 2009-03-28T15:49:35.785 2454919.159442 145.5 62.0 0.11419 0.99830 86.994 53.523 2009-03-28T16:04:42.175 2454919.169933 149.3 62.0 0.11419 0.99831 86.995 53.523 2009-03-28T16:19:39.925 2454919.180323 153.0 62.0 0.11419 0.99831 86.995 53.523 ----------------------- -------------- ----- ----- ------- ------- ------ ------- Date & Time = UTC date and time at spacecraft at moment of spacecraft measurement of event (i.e., light travel time of event detection is accounted for) Julian = Julian date and time CML = subspacecraft central meridian West longitude of Earth image at moment of image arrival at spacecraft (planetographic**) Lat = subspacecraft latitude on Earth (planetographic**) Range = range of spacecraft from Earth geocenter Helio = heliocentric range of Earth geocenter from Sun center at moment observed by spacecraft S-O-SC = Sun-object-spacecraft angle, in degrees Illum% = illumination percentage ** The oblateness of Earth is so tiny that the distinction between planetographic and planetocentric latitude is much less than the tenth-of-a-degree resolution used here. West longitude is used here for Earth, since Earth is an ordinary planet for EPOXI, like any other. Table 2 - Raw Observational Geometry Look-Up Table from HORIZONS system maintained by the JPL Solar System. JULIAN = dblarr(31) ; Julian date RA = JULIAN ; astrometric right ascension from spacecraft, in degrees DEC = JULIAN ; astrometric declination from spacecraft, in degrees ILLUM_FRAC = JULIAN ; illumination fraction (in percentage) EQ_DIAM = JULIAN ; apparent equatorial diameter, in arcsec SUBSCLON = JULIAN ; subspacecraft *East* longitude (planetographic), converted to West longitude at the end SUBSCLAT = JULIAN ; subspacecraft latitude (planetographic) SUBSUNLO = JULIAN ; subSun *East* longitude (planetographic), converted to West longitude at the end SUBSUNLA = JULIAN ; SubSun latitude (planetographic) NPPA = JULIAN ; North Pole Position Angle, ccw positive from Cel. N., in degrees RANGE_HELIO = JULIAN ; heliocentric range, in AU RANGE_TARGET = JULIAN ; geocentric range of spacecraft, in AU PHASE_ANGLE = JULIAN ; phase angle = Sun-object-spacecraft angle, in degrees SUB SUB SUB SUB JULIAN RA DEC ILL_FR EQ_DIAM SCLON SCLAT SUNLO SUNLA NPPA RANGE_HELIO RANGE_TARGET PH_ANG ------------------ --------- -------- ------ -------- ------ ----- ------ ----- -------- -------------- ---------------- ------- 2454918.000000000 99.84833 -61.54363 53.565 154.0369 275.12 +61.71 1.63 +2.78 359.8936 0.997974515292 0.11418237789687 85.9113 2454918.041666667 99.85272 -61.54249 53.564 154.0330 260.08 +61.71 346.63 +2.79 359.8936 0.997986373628 0.11418528512288 85.9129 2454918.083333333 99.85712 -61.54136 53.562 154.0291 245.05 +61.71 331.62 +2.81 359.8936 0.997998230407 0.11418813289447 85.9145 2454918.125000000 99.86151 -61.54022 53.561 154.0253 230.01 +61.71 316.62 +2.83 359.8936 0.998010085624 0.11419092121413 85.9161 2454918.166666667 99.86590 -61.53909 53.559 154.0217 214.97 +61.71 301.62 +2.84 359.8936 0.998021939277 0.11419365008446 85.9178 2454918.208333333 99.87029 -61.53795 53.558 154.0181 199.94 +61.71 286.61 +2.86 359.8936 0.998033791361 0.11419631950812 85.9194 2454918.250000000 99.87468 -61.53682 53.557 154.0145 184.90 +61.71 271.61 +2.88 359.8936 0.998045641873 0.11419892948787 85.9210 2454918.291666667 99.87907 -61.53568 53.555 154.0111 169.86 +61.71 256.61 +2.89 359.8936 0.998057490811 0.11420148002654 85.9226 2454918.333333333 99.88346 -61.53455 53.554 154.0077 154.83 +61.70 241.60 +2.91 359.8936 0.998069338172 0.11420397112703 85.9242 2454918.375000000 99.88785 -61.53341 53.552 154.0045 139.79 +61.70 226.60 +2.92 359.8936 0.998081183953 0.11420640279232 85.9259 2454918.416666667 99.89224 -61.53227 53.551 154.0013 124.75 +61.70 211.60 +2.94 359.8936 0.998093028152 0.11420877502549 85.9275 2454918.458333333 99.89662 -61.53113 53.549 153.9982 109.72 +61.70 196.59 +2.96 359.8937 0.998104870767 0.11421108782968 85.9291 2454918.500000000 99.90101 -61.53000 53.548 153.9951 94.68 +61.70 181.59 +2.97 359.8937 0.998116711796 0.11421334120812 85.9308 2454918.541666667 99.90539 -61.52886 53.547 153.9922 79.64 +61.70 166.59 +2.99 359.8937 0.998128551237 0.11421553516410 85.9324 2454918.583333333 99.90977 -61.52772 53.545 153.9893 64.61 +61.70 151.58 +3.01 359.8937 0.998140389090 0.11421766970102 85.9341 2454918.625000000 99.91415 -61.52658 53.544 153.9865 49.57 +61.70 136.58 +3.02 359.8937 0.998152225353 0.11421974482233 85.9357 2454918.666666667 99.91854 -61.52544 53.542 153.9838 34.53 +61.70 121.58 +3.04 359.8937 0.998164060025 0.11422176053158 85.9374 2454918.708333333 99.92292 -61.52430 53.541 153.9811 19.50 +61.69 106.58 +3.06 359.8937 0.998175893106 0.11422371683238 85.9390 2454918.750000000 99.92729 -61.52315 53.539 153.9786 4.46 +61.69 91.57 +3.07 359.8937 0.998187724596 0.11422561372843 85.9407 2454918.791666667 99.93167 -61.52201 53.538 153.9761 349.42 +61.69 76.57 +3.09 359.8937 0.998199554493 0.11422745122352 85.9424 2454918.833333333 99.93605 -61.52087 53.536 153.9737 334.39 +61.69 61.57 +3.11 359.8937 0.998211382799 0.11422922932149 85.9440 2454918.875000000 99.94043 -61.51972 53.535 153.9714 319.35 +61.69 46.56 +3.12 359.8937 0.998223209514 0.11423094802629 85.9457 2454918.916666667 99.94480 -61.51858 53.534 153.9691 304.31 +61.69 31.56 +3.14 359.8937 0.998235034637 0.11423260734191 85.9474 2454918.958333333 99.94918 -61.51743 53.532 153.9670 289.28 +61.69 16.56 +3.15 359.8937 0.998246858171 0.11423420727246 85.9491 2454919.000000000 99.95355 -61.51629 53.531 153.9649 274.24 +61.69 1.55 +3.17 359.8937 0.998258680116 0.11423574782210 85.9508 2454919.041666667 99.95792 -61.51514 53.529 153.9629 259.20 +61.69 346.55 +3.19 359.8937 0.998270500473 0.11423722899508 85.9525 2454919.083333333 99.96230 -61.51400 53.528 153.9610 244.17 +61.68 331.55 +3.20 359.8937 0.998282319245 0.11423865079571 85.9542 2454919.125000000 99.96667 -61.51285 53.526 153.9592 229.13 +61.68 316.54 +3.22 359.8937 0.998294136432 0.11424001322840 85.9559 2454919.166666667 99.97104 -61.51170 53.525 153.9574 214.09 +61.68 301.54 +3.24 359.8937 0.998305952037 0.11424131629763 85.9576 2454919.208333333 99.97541 -61.51055 53.523 153.9557 199.06 +61.68 286.54 +3.25 359.8937 0.998317766061 0.11424256000795 85.9593 2454919.250000000 99.97978 -61.50940 53.522 153.9541 184.02 +61.68 271.53 +3.27 359.8937 0.998329578508 0.11424374436399 85.9610 2454919.291666667 99.98414 -61.50825 53.520 153.9526 168.98 +61.68 256.53 +3.29 359.8937 0.998341389381 0.11424486937045 85.9627 2454919.333333333 99.98851 -61.50710 53.519 153.9512 153.95 +61.68 241.53 +3.30 359.8937 0.998353198681 0.11424593503213 85.9644 2454919.375000000 99.99288 -61.50594 53.517 153.9498 138.91 +61.68 226.53 +3.32 359.8937 0.998365006413 0.11424694135387 85.9661 2454919.416666667 99.99724 -61.50479 53.516 153.9485 123.87 +61.67 211.52 +3.33 359.8937 0.998376812579 0.11424788834062 85.9679 2454919.458333333 100.00161 -61.50364 53.514 153.9474 108.84 +61.67 196.52 +3.35 359.8937 0.998388617184 0.11424877599738 85.9696 2454919.500000000 100.00597 -61.50248 53.513 153.9462 93.80 +61.67 181.52 +3.37 359.8938 0.998400420231 0.11424960432924 85.9713 Code to convert from East to West longitude: SUBSCLON = 360 - SUBSCLON SUBSCLON[19:*] = 360 + SUBSCLON[19:*] SUBSUNLO = 360 - SUBSUNLO SUBSUNLO[ 1:*] = 360 + SUBSUNLO[ 1:*] SUBSUNLO[25:*] = 360 + SUBSUNLO[25:*]