PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 612 FILE_RECORDS = 1274 ^TIME_SERIES = "PPSDATA.DAT" DATA_SET_ID = "VG2-SR/UR/NR-PPS-2/4-OCC-V1.0" RING_OBSERVATION_ID = "S/OCC/VG2/PPS/1981-08-25/DELTA_SCO" PRODUCT_ID = "PPSDATA.DAT" PRODUCT_TYPE = EDITED_DATA PRODUCT_CREATION_TIME = 2000-06-01T16:00:00 SOURCE_PRODUCT_ID = "PS1D01.DAT" SPACECRAFT_NAME = "VOYAGER 2" SPACECRAFT_ID = VG2 INSTRUMENT_NAME = "PHOTOPOLARIMETER SUBSYSTEM" INSTRUMENT_ID = PPS TARGET_NAME = "S RINGS" START_TIME = 1981-08-25T23:47:47.426 STOP_TIME = 1981-08-26T01:55:11.418 SPACECRAFT_CLOCK_START_COUNT = "44001:06:601" SPACECRAFT_CLOCK_STOP_COUNT = "44003:45:800" OBSERVATION_TYPE = OCCULTATION_PROFILE OCCULTATION_TYPE = STELLAR STAR_NAME = "DELTA SCO" FEATURE_NAME = "RING SYSTEM" RING_OCCULTATION_DIRECTION = EGRESS PLANETARY_OCCULTATION_FLAG = N WAVELENGTH = 0.264 /* microns */ INSTRUMENT_MODE_ID = OC1 OBJECT = TIME_SERIES NAME = EDITED_PPS_DATA INTERCHANGE_FORMAT = BINARY ROWS = 1274 COLUMNS = 4 ROW_BYTES = 612 SAMPLING_PARAMETER_NAME = RECORD_INDEX SAMPLING_PARAMETER_UNIT = 'N/A' MINIMUM_SAMPLING_PARAMETER = 0 MAXIMUM_SAMPLING_PARAMETER = 1273 SAMPLING_PARAMETER_INTERVAL = 1 DESCRIPTION = "This is a sample data file for use with the PDS Rings Node Profile Library. It is based on file EDITDATA/PS1D01.DAT from the Voyager PPS ring occultation data set, volume VG_2801. This is a table of edited PPS photon counts plus FDS time tags. This file has been derived from raw files archived in the RAWDATA directory. It has been edited for scientific validity and has been converted to a reduced binary format. Each record contains 600 OC-1 PPS sample values, followed by a Flight Data System (FDS) time tag consisting of hour, minute, and second values. The time tag refers to the beginning moment of the record. Records are chronological and sequential; no gaps are present. Missing samples are indicated by a value of 255; invalid samples are indicated by a value of 254. This particular file contains the data from the delta Sco ring occultation experiment at Saturn, in OC-1 mode. This file was constructed from RAWDATA/PS1R01.DAT. The following processing steps were performed: 1) Program EXTRACT.FOR was used to extract records 115-1388. The first 114 records contained much larger values unrelated to the ring occultation. They were also separated from the extracted data by a short gap. 2) Program EDITDATA.FOR was used to eliminate several zero-valued samples in the first and last records. These were replaced by the MISSING_CONSTANT flag: Record=1, sample=1-240 Record=1274, sample=480-600 3) Program CLIPDATA.FOR was used to mark with INVALID_CONSTANT several isolated samples whose values were statistically impossible, based on Poisson statistics: Record=276, value=87, probability=5.3e-10 Record=287, value=156, probability=0. Record=346, value=734, probability=0. Record=391, value=305, probability=4.4e-16 Record=391, value=319, probability=4.4e-16 Record=544, value=75, probability=0. 4) CLIPDATA.FOR was used on record 988 to delete all samples below 5 and greater than 84. This gave a probability of 2.6e-10 or less for the 21 deleted samples. These samples were replaced by the INVALID_CONSTANT flag. 5) Program OC1FORM.FOR re-formatted the file to reduce its size. See EDITDATA/DATAINFO.TXT for more details of the file processing steps. FORTRAN source code for programs used in the creation of this data file can be found in directory DOCUMENT/EDITDATA. All are included in this data set for documentation purposes only and are not otherwise supported." OBJECT = COLUMN NAME = PPS_PHOTON_COUNTS DATA_TYPE = UNSIGNED_INTEGER START_BYTE = 1 BYTES = 600 ITEMS = 600 ITEM_BYTES = 1 UNIT = 'N/A' MISSING_CONSTANT = 255 INVALID_CONSTANT = 254 DESCRIPTION = "This column contains a sequence of 600 individual OC-1 mode PPS photon counts, each separated by 10 msec. Missing samples are indicated by a value of 255; invalid samples are indicated by a value of 254." END_OBJECT = COLUMN OBJECT = COLUMN NAME = VOYAGER_FDS_HOUR DATA_TYPE = LSB_INTEGER START_BYTE = 601 BYTES = 4 UNIT = 'N/A' DESCRIPTION = "Voyager FDS hour corresponding to the beginning time of the data record. Each FDS hour is equivalent to 48 minutes." END_OBJECT = COLUMN OBJECT = COLUMN NAME = VOYAGER_FDS_MINUTE DATA_TYPE = LSB_INTEGER START_BYTE = 605 BYTES = 4 UNIT = 'N/A' DESCRIPTION = "Voyager FDS minutes corresponding to the beginning time of the data record. Each FDS minute is equivalent to 48 seconds, or 1/60 of an FDS hour." END_OBJECT = COLUMN OBJECT = COLUMN NAME = VOYAGER_FDS_SECOND DATA_TYPE = LSB_INTEGER START_BYTE = 609 BYTES = 4 UNIT = 'N/A' DESCRIPTION = "Voyager FDS seconds corresponding to the beginning of the data record. For the PPS instrument, each FDS second is equivalent to 1/800 of an FDS minute, or 0.06 seconds. Note that seconds are numbered from 1 to 800 inclusive, not 0 to 799." END_OBJECT = COLUMN END_OBJECT = TIME_SERIES END