Galileo Orbiter at Pre-Jupiter Trajectory Data Readme Introduction ============ This document contains information pertaining to the Galileo Orbiter at Pre-Jupiter Trajectory Data Bundle. All data are stored in ASCII tables. All files give time values in Spacecraft Event Time (SCET). Some files may give an additional time column that contains the Earth Received Time (ERT) in addition to the SCET. Users of these data are encouraged to acknowledge both the PDS and the principal investigators of the instruments whose data is used in analysis in all publications. This bundle is organized into 8 collections, including: Galileo Trajectory Pre-Jupiter Cruise RTN Data Collection (urn:nasa:pds:galileo-traj-prejup:data-cruise) Galileo Trajectory Pre-Jupiter Earth1 GSE and GSM Coordinates Data Collection (urn:nasa:pds:galileo-traj-prejup:data-e1-gse-gsm-coords) Galileo Trajectory Pre-Jupiter Earth1 GSE and GSM Coordinates Data Collection (urn:nasa:pds:galileo-traj-prejup:data-e2-gse-gsm-coords) Galileo Trajectory Pre-Jupiter Earth1 Flyby Data Collection (urn:nasa:pds:galileo-traj-prejup-cal:data-earth1) Galileo Trajectory Pre-Jupiter Earth2 Flyby Data Collection (urn:nasa:pds:galileo-traj-prejup-cal:data-earth2) Galileo Trajectory Pre-Jupiter Asteroid Gaspra Flyby Data Collection (urn:nasa:pds:galileo-traj-prejup:data-gaspra) Galileo Trajectory Pre-Jupiter Asteroid Ida Flyby Data Collection (urn:nasa:pds:galileo-traj-prejup:data-ida) Galileo Trajectory Pre-Jupiter Venus Data Collection (urn:nasa:pds:galileo-traj-prejup:data-venus). PDS4 documentation is all XML. There is an XML label for every product in the archive. Galileo Trajectory Pre-Jupiter Cruise RTN Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory during the interplanetary cruise. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in RTN coordinates. The SPICE SPK files used to derive these products are: GLL_LONG_2.BSP; GLL910314.BSP; GLL911107.BSP; GLL921228.BSP. Galileo Trajectory Pre-Jupiter Earth1 GSE and GSM Coordinates Data Description ============================================================================ This collection contains the Galileo spacecraft trajectory during the Earth 1 flyby. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in both Geocentric Solar Ecliptic (GSE) and Geocentric Solar Magnetic (GSM) coordinates and are given in units of earth radii where 1 Re = 6378 km. The SPK file used to derived this product was: GL_LONG2.BSP Galileo Trajectory Pre-Jupiter Earth2 GSE and GSM Coordinates Data Description ============================================================================ This collection contains the Galileo spacecraft trajectory during the Earth 2 flyby. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in both Geocentric Solar Ecliptic (GSE) and Geocentric Solar Magnetic (GSM) coordinates and are given in units of earth radii where 1 Re = 6378 km. The SPK file used to dervied this product was: GLL920818.SPK. Galileo Trajectory Pre-Jupiter Earth1 Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory during the Earth-1 flyby. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in both Geocentric Solar Ecliptic (GSE) and Geocentric Solar Magnetic (GSM) coordinates and are given in units of earth radii (Re) where 1 Re = 6378 km. These data cover the interval 1990-11-05 to 1991-01-01. The trajectory has been derived from the Galileo SPK kernel: S970311A.BSP. This kernel was obtained by the PDS-PPI node from the PDS-NAIF node. Galileo Trajectory Pre-Jupiter Earth2 Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory during the Earth-2 flyby. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in both Geocentric Solar Ecliptic (GSE) and Geocentric Solar Magnetic (GSM) coordinates and are given in units of earth radii (Re) where 1 Re = 6378 km. These data cover the interval 1992-11-03 to 1992-12-20. The trajectory has been derived from the Galileo SPK kernel: S970311A.BSP. This kernel was obtained by the PDS-PPI node from the PDS-NAIF node. Galileo Trajectory Pre-Jupiter Asteroid Gaspra Flyby Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory data sampled every minute for Oct. 29 and 30, 1991. The spacecraft closest approach to the asteroid was at 22:36:40 at a range of about 1600 km. The trajectory data are provided in two coordinate systems, Gaspra-centric Solar Ecliptic (GaSE) and Heliographic (HG) coordinates. The position of the spacecraft has been extracted from the SPICE kernels provided by the project. The time tags are the exact times for which the S/C position was calculated. The time tag is spacecraft event time (SCET) given in universal time (UT). These data cover the interval 1991-10-29T06:00 to 1991-10-31 00:00. Galileo Trajectory Pre-Jupiter Asteroid Ida Flyby Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory data sampled every minute for Aug. 28, 1993. The spacecraft closest approach to the asteroid was at 16:52:07 at a range of about 2410 km. The trajectory data are provided in two coordinate systems, Ida-centric Solar Ecliptic (IdaSE) and Heliographic (HG) coordinates. The position of the spacecraft has been extracted from the SPICE kernels provided by the project. The time tags are the exact times for which the S/C position was calculated. The time tag is spacecraft event time (SCET) given in universal time (UT). These data cover the interval 1993-08-28 00:00 to 1993-08-28 23:59. Galileo Trajectory Pre-Jupiter Venus Data Collection ============================================================================ This collection contains the Galileo spacecraft trajectory during the Venus flyby. The data have been derived from SPICE kernels at a 1 minute sample rate. The data are provided in Venus Solar Orbital (VSO) coordinates and are given in units of Venus radii where 1 Rv = 6052 km. These data cover the interval 1990-02-09 00:00 to 1990-02-11 00:00. These data were originally archived in the following PDS3 data sets: GO-SS-POS-6-SUMM-CRUISE-RTN-V1.0 (https://doi.org/10.17189/1519695), GO-E-POS-6-SUMM-E1-GSE/GSM-COORDS-V1.0 (https://doi.org/10.17189/1519650), GO-E-POS-6-SUMM-E2-GSE/GSM-COORDS-V1.0 (https://doi.org/10.17189/1519651), GO-E-POS-6-EARTH1-FLYBY-TRAJ-V1.0 (https://doi.org/10.17189/1519648), GO-E-POS-6-EARTH2-FLYBY-TRAJ-V1.0 (https://doi.org/10.17189/1519649), GO-A-POS-6-GASPRA-FLYBY-TRAJ-V1.0 (https://doi.org/10.17189/1519624), GO-A-POS-6-IDA-FLYBY-TRAJ-V1.0 (https://doi.org/10.17189/1519625), GO-V-POS-6-VENUS-TRAJECTORY-V1.0 (https://doi.org/10.17189/1519701). ============================================================================ Mission Facts ============================================================================ The Galileo spacecraft and some science instruments were reprogrammed after arrival at Jupiter so that data acquisition and downlink could be achieved at the low bit rates associated with the mission after the high gain antenna (HGA) anomaly. New software was telemetered to the spacecraft in early May 1996 in a period known as the 'Inflight Load' or IFL. The mission prior to the IFL is known as the Phase 1 mission. After the IFL the mission is referred to as the Phase 2 mission. In Phase 1 raw data were provided to the instrument teams in Experiment Data Record (EDR) format. In Phase 2, the whole telemetry stream and ground data system were changed. The raw data were 'packetized' and delivered electronically as packet files or instrument packet files (IPF). The difference between a packet file and an IPF is a single 44 byte header called an SFDU. The Io data stored on this Bundle were acquired during Phase 1 and downlinked after the IFL by use of the new capabilities of the Phase 2 flight software. As such, they are a hybrid form of data that were acquired by using flight software that may differ from other files of the same raw data format. This is primarily of concern when instrument reprogramming has resulted in a change in the contents of the raw data (i.e. MAG).The data are derived from SPICE SP kernels which are archived at the NAIF Node of the PDS. The Galileo orbits were named by concatenating the first letter of the name of the primary target in each orbit with the orbit number. Thus, the fourth Jupiter orbit, in which Europa is the primary target, is called E4. The project defined orbits according to spacecraft command load boundaries rather than the normal convention of apoapsis to apoapsis. The navigation team did not always adhere to this convention, causing some confusion. The PDS has organized the data and data delivery schedules around the project defined orbit boundaries. The following tables contain information about the orbital tour and satellite encounters: Mission Phase Name Start Date End Date Targets(s) Launch 1989-10-17T00:00 1989-10-26T16:00 N/A Interplanetary Cruise 1989-10-26T16:00 1995-10-09T00:00 Solar Wind Earth-Venus Cruise 1989-10-26T16:00 1990-02-19T00:00 Solar Wind 4-Day Checkout 1989-12-27T00:00 1989-12-31T00:00 Solar Wind Venus Encounter 1990-02-07T00:00 1990-02-19T00:00 Venus Venus-Earth Cruise 1990-02-19T00:00 1991-04-29T00:00 Solar Wind Earth1 Encounter 1990-11-08T00:00 1990-12-16T00:00 Earth Earth-Earth Cruise 1991-04-29T00:00 1993-04-12T00:00 Solar Wind Gaspra Encounter 1991-10-29T22:36 1991-10-29T22:36 Gaspra Earth2 Encounter 1992-11-08T00:00 1992-12-20T00:00 Earth Earth-Jupiter Cruise 1993-04-12T00:00 1995-10-09T00:00 Solar Wind Ida Encounter 1993-08-28T16:52 1993-08-28T16:52 Ida Shoemaker-Levy 9 Encounter 1994-07-16T00:00 1994-07-22T00:00 Solar Wind Errata ====== An errata file has been included. If more issues are discovered, they will be noted in this file. Every effort has been made to insure that the data are of the best quality available. However, users are encouraged to verify the correctness of the data prior to submitting any publications or other work based on these data and report any issues to PDS/PPI. ============================================================================ Contacts ============================================================================ For questions or problems regarding this archive, please contact the PDS/PPI PDS operator: Email pds_operator@igpp.ucla.edu