Data Set Overview : The first Cassini Solar Conjunction Experiment (SCE1) Raw Data Archive is a time-ordered collection of radio science raw data acquired during the Quiet Cruise subphase of the Cassini mission. The DATA_SET_ID 'CO-SS-RSS-1-SCE1-V1.0' includes the following components: Instrument host (i.e., 'CO' for CASSINI ORBITER) Target (i.e., 'SS' for Solar System) Instrument (i.e., 'RSS' for Radio Science Subsystem) Data processing level number (i.e., '1') Description (i.e., 'SCE1') Version number (i.e., 'V1.0') Two types of measurements were obtained; these are known as closed-loop and open-loop recordings. The closed-loop system uses a phase-lock loop in the receiver to track the downlink signal, reporting both amplitude and frequency 10 times per second. In the open-loop system, the signal is simply converted to a baseband frequency range; the entire passband is sampled and recorded at 1000 samples per second. The data set includes three primary data types. Archival Tracking Data Files (ATDFs or TDFs) are the most primitive (and most voluminous) product of the closed-loop system. Orbit Data Files (ODFs) are compressed versions of ATDFs, specifically targeted to spacecraft navigators and scientists interested in gravity fields. Radio Science Receiver (RSR) files are the primary data type from the open-loop system. Parameters : The ATDF is the primary output from the Cassini closed-loop system. Each ATDF in the data set is accompanied by a full PDS label which defines both the content and the format (at the bit level) of the file. ATDF data fields include: High- or low-rate Doppler Range Uplink frequencies (ramps) Differential Range vs Integrated Doppler (DRVID) Allan deviation Smoothed noise Other information in ATDF data records includes sample date and time; spacecraft ID; ground station and its configuration; status flags and values reported by various ground systems; calibration values, noise estimates, and tolerances (station delay, transmitter power, etc.); and signal strength. The ODF is a compressed version of the ATDF. It contains the most important information (range, Doppler and frequency ramps) needed by spacecraft navigators, and investigators interested in determining gravitational fields. Each ODF is accompanied by a full PDS label which describes both the content and format of the associated file. ODF data fields include: One-way Doppler (Hertz) Two-way Doppler (Hertz) Three-way Doppler (Hertz) SRA planetary operational discrete spectrum range (range units) The Radio Science Receiver (RSR) files are the primary output from the Cassini open-loop system and they contain 16-bit samples of receiver output. Each RSR file is accompanied by a full PDS label which describes both the content and format of the file at the bit level. Processing : The open-loop Radio Science Receiver (RSR) files are screened for gaps. No gaps were found in the RSR files for SCE1. ATDFs are screened for data/contents problems, which are corrected if/as possible before the files are released by the JPL multimission Radio Metric Data Conditioning Team (RMDCT). ODFs are abstracted from subsets of ATDF data by the RMDCT. The closed-loop Tracking Data Files (TDFs : ATDFs) and Orbit Data Files (ODFs) for Cassini SCE1 are constructed to contain the data for a single day (approximately). Specifically, the file for any day consists of the Goldstone data (which started around 0-hour of that day, but possibly as much as 2 hours earlier), the subsequent Canberra data (which occurred around midday), and the Madrid data (which occurred during the final several hours of the day, but possibly into the next day) through end of track. This results in two items that require special attention when processing the TDF data files:1. There are extraneous Madrid data at the beginning of thefile (which overlap Goldstone data, by about 20 minutes)that can not be processed because the required uplinkinformation (ramps table) is not present -- these sameDoppler data are present, and must be processed, on thepreceding day's TDF (at the end).2. Likewise, the 3-way Doppler for Goldstone at the beginningof the file can not be processed because it, too, requiresthe Madrid uplink information; and must, therefore, alsobe processed on the preceding day's TDF (at the end). This is presented graphically in the following diagram (where ':' denotes station Transmitter handover):ATDF Contents:-------------- 3-way 2-way |-:---|----:-| Canberra 3-way 2-way 3-way |-:---|---------------------------:-| |-:---|... Goldstone Goldstone2-way 3-way 2-way...:-| |-:---|---------------:-|Madrid MadridProcessing:----------- N-1 N+1------>| N (^^^^^|-->(^^^^^|----------------------------------------------------------->| u/l ~24 hours Primary Data : The primary data are stored on DVD volumes in subdirectories TDF, ODF, and RSR in per-day directories SCE1_ddd (where ddd specifies the day of year based on the start time of the data). Users should refer to the INDEX/CUMINDEX.TAB listing to locate primary data files. ATDFs are stored in the TDF directory on archival volumes. File names are of the form sssttaayyyy_ddd_hhmmxuuwVn.TDF, where 'sss' is the sequence/orbit id (e.g., C32), 'tt' is the target id (e.g., EA),'aa' is the activity/experiment id (e.g., SC), 'yyyy_ddd_hhmm' is the date and time for the start of included data (e.g., 2002_160_0000), 'xuu' is the transmitter band and uplink station (e.g., K25), 'w' is the ground mode or 'way' (e.g., 2 for 2-way) and Vn is the file version number (e.g., V0). The PDS label has file name sssttaayyyy_ddd_hhmmxuuwVn.LBL. The typical ATDF contains about 46 Mbytes. ODFs are stored in the ODF directory on archival volumes. File names are of the form sssttaayyyy_ddd_hhmmxuuwVn.ODF. The PDS label has file name sssttaayyyy_ddd_hhmmxuuwVn.LBL. The typical ODF contains about 3 Mbytes. RSR files are stored in the RSR directory on archival volumes. File names are of the form sssttaayyyy_ddd_hhmmxuudrrD.rcs, where 'drr' is the downlink band and receiving station (e.g., K25) and 'rcs' is the RSR, channel and subchannel that were used to collect the data (e.g., 1A1). The PDS label has file name sssttaayyyy_ddd_hhmmxuudrrD.LBL. The typical RSR contains from about 30 Mbytes to about 165 Mbytes depending Doppler mode and station (i.e., track duration). Secondary Data : Secondary data are needed for proper analysis and interpretation of the radio data (file types TDF, ODF, and RSR). Secondary data that cover a time span of less than 24 hours are stored in subdirectories of SCE1_ddd (i.e., 158, 515, PD1, PD2 and TLM). Secondary data that cover a time span greater than 24 hours are provided in subdirectories CKF, EOP, ION, SPK and TRO in the SCE1_ANCILLARY directory. Users should refer to the INDEX/CUMINDEX.TAB listing to locate secondary data files. 0158-Monitor Files (158 Directory) --------------------------------------------------- 0158-Monitor files are ASCII files with names sssttaayyyy_ddd_hhmm_hhmmrr.158 where 'hhmm_hhmm' is the start and end time of the file and 'rr' is the receiving station. They are channelized DSN Monitor Data files (new format) and they are produced at JPL by a Query Server operating on DSN Monitor packets stored in the JPL Telemetry Delivery System (TDS) Data Base. Each 0158-Monitor file is accompanied by a PDS label with file name sssttaayyyy_ddd_hhmm_hhmmrr.LBL. Typical file size is 10 MB. The available 0158-Monitor channels, their names, and definitions are: 0158-Monitor Name Definition Channel # M-0804 AZESTMP1 Average monopulse receiver estimated azimuth error - first second M-0805 ELESTMP1 Average monopulse receiver estimated elevation error - first second M-0806 AZESTMP2 Average monopulse receiver estimated azimuth error - second second M-0807 ELESTMP2 Average monopulse receiver estimated elevation error - second second M-0808 AZESTMP3 Average monopulse receiver estimated azimuth error - third second M-0809 ELESTMP3 Average monopulse receiver estimated elevation error - third second M-0810 AZESTMP4 Average monopulse receiver estimated azimuth error - fourth second M-0811 ELESTMP4 Average monopulse receiver estimated elevation error - fourth second M-0812 AZESTMP5 Average monopulse receiver estimated azimuth error - fifth second M-0813 ELESTMP5 Average monopulse receiver estimated elevation error - fifth second M-0814 AZCORMP Accumulated azimuth correction M-0815 ELCORMP Accumulated elevation correction M-0816 AALPHA Aberration angle off boresight M-0817 ABETA Aberration clock angle of uplink beam M-0818 CNSCNTYP Conscan type M-0819 RCVSNR Monopulse Receiver SNR M-0820 ABCX Aberration table x-position M-0821 ABCY Aberration table y-position M-0822 ABER Aberration correction MON-5-15 Files (515 Directory) --------------------------------------------------- MON-5-15 files are ASCII files with names sssttaayyyy_ddd_hhmm_hhmmrr.515 where 'hhmm_hhmm' is the start and end time of the file and 'rr' is the receiving station. They are channelized DSN Monitor Data files (old format) and they are produced at JPL by a Query Server operating on DSN Monitor packets stored in the JPL Telemetry Delivery System (TDS) Data Base. Each MON-5-15 file is accompanied by a PDS label with file name sssttaayyyy_ddd_hhmm_hhmmrr.LBL. Typical file size is 25 MB. The available MON-5-15 channels, their names, and definitions are: MON-5-15 Name Definition Channel # M-0037 SC_NUM Spacecraft Code M-0300 ANT A ID Receiving Antenna 'A' ID M-0301 ANT A EL VAL Parameter Descriptor Word (PDW) Validity Field for Receiving Antenna 'A' Elevation Angles M-0304 ANT A EL ANG Receiving Antenna 'A' Elevation Angle in Floating Point Format in Units of Degrees M-0308 A CNSCN Receiving Antenna 'A' Conscan Drive Status M-0309 A CNSCN LOOP Receiving Antenna 'A' Conscan Loop Status M-0340 A A VAL PDW Validity Field for Receiving Antenna 'A' Receiver 'A' M-0343 A RCVA LOCK Receiving Antenna 'A' Receiver 'A' Lock Status M-0344 A RCVA STAT Receiving Antenna 'A' Receiver 'A' Status M-0346 A RCVA BAND Receiving Antenna 'A' Receiver 'A' Band M-0349 A RCVA AGC Receiving Antenna 'A' Receiver 'A' Signal Level Auto Gain Control (AGC) M-0350 A A PPM VAL Validity Field for Receiving Antenna 'A' Precision Power Monitor (PPM) Data M-0370 A B VAL PDW Validity Field for Receiving Antenna 'A' Receiver 'B' M-0373 A RCVB LOCK Receiving Antenna 'A' Receiver 'B' Lock Status M-0374 A RCVB STAT Receiving Antenna 'A' Receiver 'B' Status M-0376 A RCVB BAND Receiving Antenna 'A' Receiver 'B' Band M-0379 A RCVB AGC Receiving Antenna 'A' Receiver 'B' Signal Level AGC M-0380 A B PPM VAL Validity Field for Receiving Antenna 'A' Receiver 'B' PPM Data M-0215 RTC2 LOCK Real-Time Telemetry Combiner (RTC) Channel 2 Lock Status M-0311 A C1 DOP MD Doppler Mode Antenna 'A' Channel 1, S Band M-0312 A C1 REQ DOP Requested Doppler Sample Rate Antenna 'A' Channel 1 M-0314 A C2 DOP MD Doppler Mode Antenna 'A' Channel 2, X Band M-0315 A C2 REQ DOP Requested Doppler Sample Rate Antenna 'A' Channel 2 M-0500 TXR ANT ID Transmitting Antenna ID M-0501 L TXR VAL Validity Field for Low-Power Transmitter Data M-0504 L PWR TXR ID Transmitter ID M-0509 L PWR TX PWR Transmitter Power M-0511 H TXR VAL Validity Field for High-Power Transmitter Data M-0524 EXCITER FREQ Exciter Frequency M-0600 DOP VAL Validity Field for Doppler Data from the Metric Data Assembly (MDA) Data M-0612 DOP BIAS X X Band Doppler Bias Frequency M-0611 DOP NOISE X X Band Doppler Noise M-0613 NUM SLIP X X Band # Slipped Cycles M-0614 DOP RES X X Band Doppler Residual M-0626 DOP CNT X X Band Doppler Count M-0627 DOP CNT X FR Fractional Part of X Band Doppler Count M-0605 RNG VAL Validity Field for Range Data from the MDA Data M-0320 APA A VAL Validity Field for Antenna Processing Assembly (APA) Antenna 'A' Angles M-0305 ANT A AZ ANG Receiving Antenna 'A' Azimuth Angle in Double Integer Format in Units of Degrees M-0306 ANT A AZ RES Receiving Antenna 'A' Azimuth Angle Residual M-0324 ANT A EL ANG Receiving Antenna 'A' Elevation Angle in Double Integer Format in Units of Degrees. M-0307 ANT A EL RES Receiving Antenna 'A' Elevation Angle Residual M-0660 SBR MOV Subreflector Moving Message Moving Flag M-0663 SBR MOV TIME Time of Latest Subreflector Moving Message Received for M-0660 M-0670 SBR FIX Subreflector Fixed Message Moving Flag M-0673 SBR FIX TIME Time of Latest Subreflector Moving Message Received for M-0670 M-0723 AA5 PCNO Antenna A Receiver A Block V Receiver (BVR) Channel Signal-to-Noise Ratio M-0724 AA5 SNT VAL Antenna A Receiver A BVR Validity Field for BVR System Noise Temperature Data M-0725 AA5 SNT Antenna A Receiver A BVR System Noise Temperature M-0739 AA5 LBW Antenna A Receiver A BVR Carrier Loop Bandwidth M-0773 AB5 PCNO Antenna A Receiver B Block V Receiver (BVR) Channel Signal-to-Noise Ratio M-0774 AB5 SNT VAL Antenna A Receiver B BVR Validity Field for BVR System Noise Temperature Data M-0775 AB5 SNT Antenna A Receiver B BVR System Noise Temperature M-0789 AB5 LBW Antenna A Receiver A BVR Carrier Loop Bandwidth M-0616 RNG MOD X X Band Ranging Modulation Indicator M-0316 ANT A SRC Antenna A Source Code M-0310 A POL S BD Antenna A Polarization, S-Band M-0313 A POL X BD Antenna A Polarization, X-Band Path Delay Files (PD1 and PD2 Directories) ----------------------------------------------------------- Path Delay files are ASCII files and they are produced by the RSSG at JPL. File names have the form sssttaayyyy_ddd_hhmm_hhmmrr.PD1 (stored in the PD1 directory - the '1' in 'PD1' indicates that the data have been collected from Advanced Water Vapor Radiometer (AWVR) Unit 1) and sssttaayyyy_ddd_hhmm_hhmmrr.PD2 (stored in the PD2 directory - the '2' in 'PD2' indicates that the data have been collected from AWVR Unit 2) where 'hhmm_hhmm' is the start and end time of the data and rr is the receiving station. Each Path Delay file is accompanied by a PDS minimal label with file name sssttaayyyy_ddd_hhmm_hhmmrr.LBL. Typical file size is 135 KB. Telemetry Files (TLM Directory) --------------------------------------------------- Telemetry files are ASCII files with names sssttaayyyy_ddd_hhmm_hhmm.TLM where 'hhmm_hhmm' is the start and end time of the file. They are channelized DSN Telemetry Data files and they are produced at JPL by a Query Server operating on DSN Telemetry packets stored in the JPL Telemetry Delivery System (TDS) Data Base. Each Telemetry file is accompanied by a PDS label with file name sssttaayyyy_ddd_hhmm_hhmm.LBL. Typical file size is 50 MB. The available Telemetry channels, their names and definitions are: Telemetry Name Definition Channel # S-0181 KAT_UNLOCK Ka-Band Translator (KAT) Receiver Lock Latch S-0182 SBT_STATE_SW S-Band Transmitter (SBT) On/Off State (Commanded Mode) S-0183 KAT_STATE_SW KAT On/Off State (Commanded Mode) S-0185 KEX_STATE Ka-Band Exciter (KEX) On/Off State S-0186 KAT_STATE_HW KAT Off/On (Actual Status) S-0188 KTWT_SBY_HW Ka-Band Traveling Wave Tube Amplifier (KATWTA) Standby Enable/Inhibit (Actual Status) S-0189 KAT_RCVR_LCK KAT Receiver Locked/Unlocked S-0190 SBT_STATE_HW SBT Off/On (Actual Status) S-0191 SBT_REF_HW SBT Reference (Actual Status) S-0192 SBT_REF_SW SBT Reference (Commanded Mode) S-0193 KTWT_SBY_SW KATWTA Standby Enable/Inhibit (Commanded Mode) S-0166 KTWT_P_IN_r KATWTA Input Power Level (Residual) S-0164 KTWT_P_OUT_r KATWTA Output Power Level (Residual) S-0100 KAT_SPE_a KAT Receiver Static Phase Error (Telemetry Control Unit (TCU) A) S-0102 SBT_P_OUT_a SBT Output Power Level (TCU A) S-0104 KEX_P_OUT_a KEX Output Power Level (TCU A) S-0106 KEX_X_PWR_a KEX X-Band Power Level (TCU A) S-0108 KEX_PCV_a KEX Power Conv Voltage (TCU A) S-0112 KTWT_HLX_I_a KATWTA Helix Current (TCU A) S-0114 KTWT_P_OUT_a KATWTA Output Power Level (TCU A) S-0116 KTWT_P_IN_a KATWTA Input Power Level (TCU A) S-0118 KTWT_CTH_I_a KATWTA Cathode Current (TCU A) S-0120 KAT_TEMP_a KAT Temperature (TCU A) S-0122 SBT_TEMP_a SBT Temperature (TCU A) S-0124 KTWT_TEMP_a KATWTA Temperature (TCU A) S-0126 KEX_TEMP_a KEX Temperature (TCU A) S-0128 KTWT_CURR_a KATWTA Prime Current (TCU A) C-Kernel Files (CKF Directory) --------------------------------------------------- C-Kernel Files are in transfer format and they are produced by the Cassini Attitude and Articulation Control Subsystem team (AACS). File names have the form sssttaayyyy_ddd_yyyy_ddd.CKF where 'yyyy_ddd_yyyy_ddd is the start and end time of the file. Each C-Kernel file is accompanied by a PDS minimal label with file name sssttaayyyy_ddd_yyyy_ddd.LBL. Typical file size is 18 MB. Earth Orientation Parameter files (EOP Directory) --------------------------------------------------- Earth Orientation Parameter files are ASCII files and they are produced by the Kalman Earth Orientation Filter (KEOF) Group at JPL. File names have the form sssttaayyyy_ddd_yyyy_ddd.EOP. Each EOP file is accompanied by a PDS minimal label with file name sssttaayyyy_ddd_yyyy_ddd.LBL. Typical file size is 24 KB. Ionosphere Calibration Files (ION Directory) --------------------------------------------------- Ionosphere Calibration files are produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They provide historical and predicted Earth ionospheric conditions. File names have the form sssttaayyyy_ddd_yyyy_ddd.ION. Each ION file is accompanied by a PDS minimal label with file name sssttaayyyy_ddd_yyyy_ddd.LBL. Typical file size is 23 KB. Spacecraft/Planetary Ephemeris (SP-Kernel) Files (SPK Directory) ---------------------------------------------------------- Spacecraft/Planetary Ephemeris Files (also known as SP kernels or SPK files) are produced by the Cassini Navigation Team (NAV). These files give spacecraft and planetary ephemerides. File names have the form sssttaayyyy_ddd_yyyy_ddd.SPK. One SPK file has been included, covering SCE1 (file size 27KB). This SPK file is accompanied by a PDS minimal label with file name having the form sssttaayyyy_ddd_yyyy_ddd.LBL. Troposphere Calibration Files (TRO Directory) --------------------------------------------------- Troposphere Calibration files are produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They provide historical and predicted Earth tropospheric conditions. File names have the form sssttaayyyy_ddd_yyyy_ddd.TRO. Each TRO file is accompanied by a PDS minimal label with file name sssttaayyyy_ddd_yyyy_ddd.LBL. Typical file size is 120 KB. Files in the CALIB Directory : The CALIB directory contains a Leapsecond kernel file, a Spacecraft Clock Conversion file, and a Boresight Calibration Report. All files in the CALIB directory are ASCII text files with variable length records delimited by ASCII carriage-return line-feed pairs. All file names in this directory contain the string 'yymmdd', where yy, mm, dd indicate the year, month and day of the file creation. Leapsecond kernel files are a record of leap seconds (past and predicted) that allow proper conversion between ephemeris time and UTC. File names are of the form: LSK_yymmdd.TLS Each file LSK_yymmdd.TLS is accompanied by a PDS detached minimal label with name LSK_yymmdd.LBL. Spacecraft Clock Conversion files allow time measured by the spacecraft clock to be converted to other time systems (e.g., ephemeris time or UTC). File names are of the form: TSC_yymmdd.SCK Each file TSC_yymmdd.SCK is accompanied by a PDS detached minimal label with name TSC_yymmdd.LBL. The Boresight Calibration Reports are produced by the Radio Science Systems Group (RSSG) at JPL. The naming convention for these files is: BORESIGHT_yymmdd.TXT Coordinate System : SPK files are produced in the J2000 inertial reference frame. Other data types are not dependent on any definition of a coordinate system. Software : Software for parsing, reducing, and analyzing data such as these has been developed at JPL and elsewhere. Because such software must usually operate at the bit-level and is written for a narrow range of platforms, it is unsuitable for general distribution. As such, no software is included with this archival data set. Media/Format : The archival data set is written on DVD-R media. The DVD-R volumes conform to the 'UDF_ISO-9660_BRIDGE' structure as required by PDS.

Overview : In general, this is a good data set. Review : This archival data set was reviewed by the Cassini Radio Science Team prior to submission to the Planetary Data System (PDS). Data Coverage and Quality : The data are contained in eight volumes (DVDs). The table below lists the eight volumes and their respective contents. VOLUME_ID Start Date End Date --------- ------------------- -------------------CORS_0021 2002-06-06 (02/157) 2002-06-09 (02/160)CORS_0022 2002-06-10 (02/161) 2002-06-13 (02/164)CORS_0023 2002-06-14 (02/165) 2002-06-17 (02/168)CORS_0024 2002-06-18 (02/169) 2002-06-21 (02/172)CORS_0025 2002-06-22 (02/173) 2002-06-25 (02/176)CORS_0026 2002-06-26 (02/177) 2002-06-29 (02/180)CORS_0027 2002-06-30 (02/181) 2002-07-03 (02/184)CORS_0028 2002-07-04 (02/185) 2002-07-05 (02/186) There are no known problems with this data set. Limitations : The limitations in this data set follow from the quality of the execution, which is described above under Data Coverage and Quality.