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This description was generated automatically using input from the Planetary Data System. Overview: ========= This data set contains Galileo trajectory data in moon (Amalthea, Io, Europa, Ganymede, Callisto) centered coordinates for all of the near satellite encounters. Ephemeris data are provided every two seconds for approximately one hour about closest approach. Coordinates: ============ Two coordinate systems are provided: SPRH (Satellite centered planetocentric, right-handed), PhiO (Satellite centered inertial Phi-Omega coordinates), Distances from the satellites are measured in satellite radii. The radii values used for the various satellites are listed in Table 1. Table 1: Satellite Radii --------------------------Moon Radius <km> --------------------------Amalthea 86.2 Io 1818 Europa 1560 Ganymede 2634 Callisto 2409 Satellite centered coordinate systems names are preceded by the first letter in the name of the satellite, in order to indicate which satellite is used as the center. In order words, PhiO coordinates are called EPhiO at Europa and CPhiO at Callisto. SPRH (Satellite centered planetocentric, right-handed) This coordinate system is the basic J2000 definition of planetocentric coordinates, as applied to each of the satellites. In it's Cartesian form the coordinate system has its Z-axis along the satellite axis of rotation positive in the direction of angular momentum, the X-axis in the equatorial plane in the direction of the prime meridian, with the Y-axis completing the right-handed set. The coordinate system rotates with the satellite (body-fixed). All of the SPRH data in this data set are based on the International Astronomical Union (IAU) definitions of the satellite axes orientations and rotation rates from the Report of the IAU/IAG/COSPAR Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites: 1994 [IAU1994]. The specific orbit elements for each satellite are summarized in Table 2. Table 2: Approximate Satellite axes orientations in J2000 Coordinates* --------------------------------------------------------------------Right Prime Meridian** Satellite Ascension Declination Const Rate -------------------------------------------------------------------Amalthea 268.05 +64.49 231.67 +722.6314560 Io 268.05 +64.50 200.39 +203.4889538 Europa 268.08 +64.51 35.67 +101.3747235 Ganymede 268.20 +64.57 44.04 +50.3176081 Callisto 268.72 +64.83 259.73 +21.5710715 * Precise definitions include drift rate and nutation corrections ** PM = const + rate*d where d is days after the J2000 epoch. PhiO (Satellite centered inertial Phi-Omega coordinates) The basis vectors of the inertial Phi-Omega coordinate systems are defined at an epoch time that is set at the time of spacecraft closest approach to the satellite. The X-direction is defined to be in the direction of corotation, at the center of the satellite at the epoch time (System III Phi direction [DESSLER1983]). The Z-axis is defined to be orthogonal to the X direction such that the X-Z plane contains the Jupiter spin axis (Omega), positive in the direction of angular momentum. The Y-axis is defined to complete the right-handed set. Since the jovian satellites all lie very close to the jovian equatorial plane, it is often convenient to visualize this coordinate system as follows: X lies in the direction of plasma flow, Y points towards Jupiter, and Z points 'up'. In this data set, the instantaneous satellite-spacecraft range vector is resolved into the Cartesian components of the coordinate system described in the previous paragraph. Table 3 gives the satellite closest approach times (epoch times) and other useful parameters. One particularly useful parameter is the angle (Theta) that the background magnetic field makes with respect to the Z-axis, when projected into the Y-Z plane. The PhiO coordinate system can be rotated about the X-axis by this angle to produce the PhiB coordinate system that has been used extensively in the analysis of the magnetic field data. Table 3: Satellite Encounter Parameters ======================================================================== SPRH values at C/A ------------------Moon Orbit C/A Time Alt.* Lat. E.Lon. Local Theta UT <km> <deg> <deg> time <deg> ----+----+------------------------------------------------------------Ama 34 2002-11-05T06:18:40 163 -47.7 74.8 21:58 Io 00 1995-12-07T17:45:58 901 -9.56 258.9 11:50 -3 Io 24 1999-10-11T04:33:03 615 4.51 135.9 10:42 15 Io 25 1999-11-26T04:05:22 309 -76.39 315.8 10:13 *** Io 27 2000-02-22T13:46:41 2013 -18.96 92.4 08:55 15 Io 31 2001-08-06T04:59:21 197 77.51 187.7 04:19 Io 32 2001-10-16T01:23:21 182 -78.60 135.3 05:03 Io 33 2002-01-17T14:08:28 163 -43.50 41.8 01:18 *** Io** 34 2002-11-05R02:56:49 26.0 -6.30 *** Eur** 03 1996-11-06T18:49:51 23.3 0.69 *** Eur 04 1996-12-19T06:52:58 697 -1.65 34.7 12:59 -23 Eur 06 1997-02-20T17:06:10 591 -17.02 270.4 19:44 *** Eur** 07 1997-04-04T05:58:47 16.7 2.1 *** Eur 11 1997-11-06T20:31:44 2048 25.73 218.7 10:57 -25 Eur 12 1997-12-16T12:03:20 206 -8.66 134.4 14:39 -4 Eur 14 1998-03-29T13:21:05 1649 12.20 131.2 14:25 -28 Eur 15 1998-05-31T21:21:56 2520 15.01 225.4 10:04 27 Eur 16 1998-07-21T05:04:43 1840 -25.61 133.6 13:49 *** Eur 17 1998-09-26T03:54:20 3587 -42.43 220.3 09:55 -16 Eur 18 1998-11-22T11:44:56 2276 41.71 139.3 13:04 *** Eur 19 1999-02-01T02:19:50 1444 30.52 28.2 09:51 -10 Eur** 25 1999-11-25T16:29:05 5.5 62.31 266.0 09:29 Eur 26 2000-01-03T17:59:43 348 -47.09 157.4 08:55 29 Gan 01 1996-06-27T06:29:07 835 30.41 246.7 11:50 -45 Gan 02 1996-09-06T18:59:34 261 79.30 236.4 10:47 -40 Gan 07 1997-04-05T07:09:58 3102 55.79 270.4 19:44 48 Gan 08 1997-05-07T15:56:10 1603 28.27 84.8 08:07 -4.5 Gan** 09 1997-06-26T17:19:35 30.3 -0.02 261.2 08:02 Gan** 12 1997-12-15T09:58:09 5.5 -5.81 266.1 06:45 Gan 28 2000-05-20T10:10:10 809 -18.96 92.4 00:47 45 Gan 29 2000-12-28T08:25:27 2338 62.21 269.0 23:54 -46 Cal 03 1996-11-04T13:34:28 261 79.30 246.7 07:48 -71 Cal 09 1997-06-25T13:47:50 1603 1.96 84.8 05:32 72 Cal 10 1997-09-17T00:18:55 529 4.60 281.3 05:02 69 Cal 20 1999-05-05T13:56:17 1315 2.78 258.3 17:50 *** Cal 21 1999-06-30T07:46:50 1042 -0.71 286.0 01:45 77 Cal 22 1999-08-14T08:30:52 2293 -2.26 252.5 18:08 66 Cal 23 1999-09-16T17:27:02 1046 0.10 249.7 17:56 -50 Cal 30 2001-05-25T11:23:58 132 13.65 254.6 13:10 * Altitude are computed by subtracting the satellite radius given in Table 1 from the range vector. ** Non-targeted encounters, Altitude column contains range in units of satellite radii. *** Encounter lost Data Sampling: ============== The data are sampled every two seconds for approximately one hour about the time of satellite closest approach. Data are time tagged with spacecraft event time (SCET), represented in Universal Time Coordinated (UTC). Data are extracted from SPICE SPK kernels at the sample time. Data are not averaged or otherwise resampled. Data Processing: ================ The trajectory data were created using code written by Steven Joy to extract information from the SPICE (GO-J-SPICE-6-SPK-V1.0) products produced by the Galileo project. The software used to create this ephemeris is well tested and in agreement with similar software provided by the Galileo project. Data: ===== These data are derived from SPICE kernels produced by the Galileo NAV team during the mission. All of the SPICE kernels used to produce this data set are contained on the MWG archive volume DVD in the EXTRAS/SPICE/KERNELS directory. The kernels (PDS PRODUCT_ID) used to create this were: S980326B.TSP - Prime Mission Reconstruction (JA - E12) S000131A.TSP - GEM reconstruction (E12-E26) S030129A.TSP - GMM (I27-A34) reconstruction, J35 predict PCK00007.TPC - Planetary constants kernel (2000-04-24) MK00062B.TSC - Galileo spacecraft clock kernel This data set is highly discontinuous which makes the stated data set start/stop time somewhat misleading. In order to avoid confusion, the start and stop times of each data product in the data set are tabulated in Table 4. Table 4: Data Product Start/Stop times ======================================================================== Start Time Stop Time Moon Orbit PRODUCT_ID UTC UTC ----+----+------------------------------------------------------------Ama 34 AMALTHEA_34_ORB.TAB 2002-11-05T05:50 2002-11-05T06:50 Io 00 IO_00_ORB.TAB 1995-12-07T17:15 1995-12-07T18:15 Io 24 IO_24_ORB.TAB 1999-10-11T04:00 1999-10-11T05:00 Io 25 IO_25_ORB.TAB 1999-11-26T03:35 1999-11-26T04:35 Io 27 IO_27_ORB.TAB 2000-02-22T13:15 2000-02-22T14:15 Io 31 IO_31_ORB.TAB 2001-08-06T04:30 2001-08-06T05:30 Io 32 IO_32_ORB.TAB 2001-10-16T00:55 2001-10-16T01:55 Io 33 IO_33_ORB.TAB 2002-01-17T13:40 2002-01-17T14:40 Eur 04 EUROPA_04_ORB.TAB 1996-12-19T06:20 1996-12-19T07:20 Eur 06 EUROPA_06_ORB.TAB 1997-02-20T16:35 1997-02-20T17:35 Eur 11 EUROPA_11_ORB.TAB 1997-11-06T20:00 1997-11-06T21:00 Eur 12 EUROPA_12_ORB.TAB 1997-12-16T11:30 1997-12-16T12:30 Eur 14 EUROPA_14_ORB.TAB 1998-03-29T12:50 1998-03-29T13:50 Eur 15 EUROPA_15_ORB.TAB 1998-05-31T20:50 1998-05-31T21:50 Eur 16 EUROPA_16_ORB.TAB 1998-07-21T04:35 1998-07-21T05:35 Eur 17 EUROPA_17_ORB.TAB 1998-09-26T03:25 1998-09-26T04:25 Eur 18 EUROPA_18_ORB.TAB 1998-11-22T11:15 1998-11-22T12:15 Eur 19 EUROPA_19_ORB.TAB 1999-02-01T01:50 1999-02-01T02:50 Eur*** 25 EUROPA_25_ORB.TAB 1999-11-25T16:00 1999-11-25T17:00 Eur 26 EUROPA_26_ORB.TAB 2000-01-03T17:30 2000-01-03T18:30 Gan 01 GANYMEDE_01_ORB.TAB 1996-06-27T06:00 1996-06-27T07:00 Gan 02 GANYMEDE_02_ORB.TAB 1996-09-06T18:30 1996-09-06T19:30 Gan 07 GANYMEDE_07_ORB.TAB 1997-04-05T06:40 1997-04-05T07:40 Gan 08 GANYMEDE_08_ORB.TAB 1997-05-07T15:25 1997-05-07T16:25 Gan*** 09 GANYMEDE_09_ORB.TAB 1997-06-26T16:50 1997-06-26T17:50 Gan*** 12 GANYMEDE_12_ORB.TAB 1997-12-15T09:50 1997-12-15T09:50 Gan 28 GANYMEDE_28_ORB.TAB 2000-05-20T09:40 2000-05-20T10:40 Gan 29 GANYMEDE_29_ORB.TAB 2000-12-28T07:55 2000-12-28T08:55 Cal 03 CALLISTO_03_ORB.TAB 1996-11-04T13:05 1996-11-04T14:05 Cal 09 CALLISTO_09_ORB.TAB 1997-06-25T13:15 1997-06-25T14:15 Cal 10 CALLISTO_10_ORB.TAB 1997-09-16T23:50 1997-09-17T00:50 Cal 20 CALLISTO_20_ORB.TAB 1999-05-05T13:25 1999-05-05T14:25 Cal 21 CALLISTO_21_ORB.TAB 1999-06-30T07:15 1999-06-30T08:15 Cal 22 CALLISTO_22_ORB.TAB 1999-08-14T08:00 1999-08-14T09:00 Cal 23 CALLISTO_23_ORB.TAB 1999-09-16T17:00 1999-09-16T18:00 Cal 30 CALLISTO_30_ORB.TAB 2001-05-25T10:55 2001-05-25T11:55 All data are archived in ASCII tables (1 orbit/file) with the following table structure: Column Type Description <units> _________________________________________________________________________ time char Sample time in PDS time format number R real SPRH range from satellite in moon radii (Rm - Table 1) LAT real SPRH latitude of the S/C <degrees> LON real SPRH east longitude of the S/C <degrees> X real PhiO X range to the S/C <Rm> Y real PhiO Y range to the S/C <Rm> Z real PhiO Z range to the S/C <Rm> Ancillary Data: =============== SPICE kernels MK98264A.TLS (leapseconds), MK98264A.TLS (spacecraft clock), PK96030A.TPC (planetary constants), S980326B.TSP, S000131A.TSP, and S020128A.TSP (spacecraft/planetary ephemeris) located in the EXTRAS/SPICE/KERNELS directory of the archive volumes can all be considered as ancillary data files for this data set. These are the files that were used to generate this data set. Ideally, these data should be generated on demand using the latest SPICE kernels available from the NAIF Node of the PDS. References: =========== Russell, C.T., Geophysical coordinate transformations, Cosmic Electrodynamics, Reidel Publishing Co., Vol. 2, 174-196, 1971. Dessler, A. J., Appendix B Coordinate Systems, in Physics of the Jovian Magnetosphere, (edited by A. J. Dessler), Cambridge Univ Press, 1983. Kivelson M.G., K.K. Khurana, S. Joy, C.T. Russell, R. J. Walker, and C. Polanskey, Europa's magnetic signature: Report from Galileo's first pass on December 19, 1996, Science, 276, P. 1239, 1997. Khurana, K.K., M.G. Kivelson, C.T. Russell, R.J. Walker, D.J. Southwood, No Intrinsic Field Associated with Callisto, Nature, 387, P. 262, 1997. Kivelson, M.G., K.K. Khurana, F.V. Coroniti, S. Joy, C.T. Russell, R.J. Walker, J. Warnecke, L. Bennett, and C. Polanskey, The magnetic field and magnetosphere of Ganymede., Geophys. Res. Lett., 24, P.2155, 1997 Kivelson M.G., K.K. Khurana, R.J. Walker, C.T. Russell, J.A. Linker, D.J. Southwood, and C. Polanskey, A Magnetic Signature at Io: Initial Report from the Galileo Magnetometer, Science, 273, P. 337, 1996.

Alternate Names



  • Planetary Science: Fields and Particles

Additional Information


Questions and comments about this data collection can be directed to: Dr. Edwin V. Bell, II



NameRoleOriginal AffiliationE-mail
Mr. Steven P. JoyData ProviderUniversity of California, Los
Mr. Steven P. JoyGeneral ContactUniversity of California, Los
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