PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM LABEL_REVISION_NOTE = " 2014-08-23 SwRI:BTCarcich Updated from comments in PDS peer review on 2014-08-19. " OBJECT = TEXT PUBLICATION_DATE = 2014-11-12 NOTE = "The NH SDC pluto cruise Raw VERSION 1.0 Data Archive Be sure to read the Required Reading note below before using the data in this archive. " END_OBJECT = TEXT END The NH SDC PLUTOCRUISE Raw VERSION 1.0 Data Archive ======================================================================== Table of Contents ================= Introduction Required Reading Processing Level Volume Format File Formats Volume Contents Data Filenames and Product IDs Data directory naming convention Suggested FITS & PDS software PDS label overview Generic PDS label details Whom to Contact for Information Introduction ============ Science data content -------------------- This document provides an overview of this dataset of the New Horizons (NH) SDC PLUTOCRUISE Raw VERSION 1.0 Data Archive, including a general listing of the dataset contents. This dataset contains flight data obtained during the pluto cruise mission phase of the New Horizons mission, taken by the Student Dust Counter instrument of the New Horizons spacecraft. Refer to the data sequence list file DOCUMENT/SEQ_SDC_PLUTOCRUISE.* for descriptions of the sequences that generated these data (see also Note 2 below). Extensive preparation is necessary to properly understand and interpret the data in this data set. Although some detail is provided here, this file is only intended as an introduction to and starting point for this data set; refer to the Required Reading section below for further guidance. Boilerplate disclaimer ---------------------- All NH raw and calibrated data sets were generated in similar fashion by an automated pipeline; as such, much of the information that follows is boilerplate common to all such NH data sets. Refer to the data set catalog (CATALOG/DATASET.CAT) and documentation (DOCUMENT/), as well as the Required Reading section below, for information specific to the instrument and data of this data set. Note about start and stop times ------------------------------- The start and stop times of data products in some NH data sets may overlap the ***NOMINAL*** start and stop times, i.e. 2007-06-27T00:00:00 and 2014-09-30T00:00:00 UTC, respectively, of that mission phase (see also Note 1 below). See the Mission catalog file NH.CAT in the /CATALOG/ directory for a description of the New Horizons mission, including a description of mission phases. Note 1: Because single data products may span from milliseconds to days of data, their start time may precede, or their stop times may follow, the mission ***NOMINAL*** phase start or stop times, respectively. Refer to CATALOG/DATASET.CAT for the exact start and stop times of data in this data set. Note 2: Some planned sequences in that list were not executed, due to operational considerations such as spacecraft safing events, so some sequences will have no corresponding data. Required Reading ================ Almost all of the New Horizons instruments have complex modes of operation and complex, multi-part data products; users who want to properly understand these data should expect to spend a significant effort (at least a day per instrument) reading about and researching the instrument, the data and the PDS product formats. To support that, the data producer has provided the following Required Reading list. Required Reading Summary List (see Details below for suggested priority) ------------------------------------------------------------------------ In this file (sections and subsections below): Details (next subsection of Required Reading) Data Filenames and Product IDs Data directory naming convention Explanation of granularity Suggested FITS & PDS software PDS label overview Under the /DOCUMENT/ subdirectory: SOC_INST_ICD.* Science Operations Center Interface Control Document SDC_SSR.* Space Science Review (SSR) Instrument paper PAYLOAD_SSR.* Space Science Review (SSR) Payload paper DOCINFO.TXT Summary of /DOCUMENT/ subdirectory NH_MISSION_TRAJECTORY.* NH Trajectory table for mission NH_TRAJECTORY.* NH Trajectory table for Jupiter Encounter SEQ_SDC_PLUTOCRUISE.* Sequence list for this data set Under the /CATALOG/ subdirectory: DATASET.CAT NH Data Set Catalog objects NH.CAT NH Mission Catalog objects NHSC.CAT NH SpaceCraft catalog objects SDC.CAT NH Instrument catalog objects REF.CAT References to other documents CATINFO.TXT Summary of /CATALOG/ subdirectory Under the /CALIB/ subdirectory: CALINFO.TXT Summary of calibration files in /CALIB/ subdirectory Details ------- The information contained in all documents included with, and referenced in, this archive, is an integral part of this archive. Specifically, the information contained in the SOC Instrument Interface Control Document (ICD), and in the documents submitted for publication in Space Science Reviews in 2007, is crucial to understanding the data in this archive. As such, the producers of this archive have included the best possible version of these documents with this archive. * SOC Instrument Interface Control Document (AKA the ICD) The ICD specifies the interfaces between the New Horizons Science Operations Center (SOC) and the instrument pipeline, which process data from raw to calibrated units. The ICD's purpose is to define the various aspects of the interfaces in sufficient detail to establish a clear understanding between the SOC and the instrument team to allow for a parallel pipeline development. This file is located in the /DOCUMENT/ directory of this data set and its filename is SOC_INST_ICD.PDF. Other versions of this file in different formats may be listed in SOC_INST_ICD.LBL. In addition to mission-wide information (approximately six pages), the ICD contains an entire section devoted to the details of the SDC instrument (~9 pages). The most important aids provided to the user of this archive by the ICD are * Descriptions of the data files that comprise the data portion of this archive. * Descriptions of the calibration methodology of the SDC instrument data. * Overview descriptions of the SDC instrument theory and operations. * References to more detailed documentation. * SDC Space Science Reviews documents (AKA SSR paper(s)) Scientific papers describing the New Horizons mission, spacecraft, mission design, payload and instruments were submitted to the publication Space Science Reviews in 2007 after the Jupiter encounter; refer to the references catalog for full citations. These files are located in the /DOCUMENT/ directory of this data set. The filename of the instrument SSR paper is SDC_SSR.PDF; other versions of this file are listed in SDC_SSR.LBL. The filename of the payload SSR paper is PAYLOAD_SSR.PDF; other versions of this file are listed in PAYLOAD_SSR.LBL. The SDC instrument and payload overview SSR papers, I.E. Horanyi, M., et al., 2008 [HORANYIETAL2008] and Weaver, H.A., et al., 2008 [WEAVERETAL2008], provide details of the SDC theory, design, ground testing and calibration, operational considerations, and post-launch checkout results. Because of time and copyright restrictions, the SSR papers could not be included in this archive in their peer-reviewed and published form. However, Space Science Reviews did agree to allowing the submitted versions of these papers to be included in this archive. This has been done with the initial version of this archive as a convenience to the user of this archive. However, it should be noted that There were changes made to the submitted papers before they were published. Where any differences exist between the submitted versions of these documents in this archive and the final published versions, the final published versions are considered authoritative, and it is up to the user of this archive to assess if any such differences will affect their use of this archive. Other important documents are available in the following files: NH Trajectory table through Jupiter Encounter: /DOCUMENT/NH_TRAJECTORY.* - Includes Jupiter-centric ephemeris in Jupiter frame NH Heliocentric Trajectory table for mission /DOCUMENT/NH_MISSION_TRAJECTORY.* SDC Field Of View definitions: /DOCUMENT/NH_FOV.* /DOCUMENT/NH_SDC_V###_TI.TXT Further pointers to important documents for this data set are available in the following files: /CATALOG/CATINFO.TXT /CATALOG/REF.CAT /CALIB/CALINFO.TXT /DOCUMENT/DOCINFO.TXT All reasonable efforts have been made to include the documents in multiple formats in the document portion of this archive. Where such inclusion was not possible due to copyright restrictions, references to the documents have been included in this archive, and it is up to the user of this archive to obtain a copy of such documents. The original format of the ICD was MSWORD, and the original format of the SSR papers was PDF, as noted above. All other formats may show some loss in quality, especially in images, so the user is encouraged to get the best possible version of these documents. Processing Level ================ This data set contains Raw data, one of the two levels of processed data provided by the NH project to PDS. A brief discussion of processing levels follows: Processing Description Level => CODMAC Level ========== =============== Raw Instrument telemetry formatted for scientific use => CODMAC Level 2 Calibrated Raw data converted to scientific units => CODMAC Level 3 N.B.: Raw and Calibrated data are sometimes referred to as EDR (Engineering Data Records) and RDR (Reduced Data Records), respectively. Raw data are in instrument units, typically binary integers referred to as COUNTs or DATA NUMBER (DN). The raw data are stored in data files with ancillary information such as observation time timestamps and observational geometry. Calibrated data are in scientific or engineering units, such as radiance (W/(m**2 um sr)) or impact particle mass (GRAMs). The conversion to calibrated data from raw data was performed according to an instrument performance model, which was developed from scientific analysis of ground- and inflight-calibrations, and which is documented in files in this data set under the DOCUMENT/ and CALIB/ subdirectories. Refer to to DOCUMENT/DOCINFO.TXT and CALIB/CALINFO.TXT for pointers to more information. N.B.: Not all data sets will have CALIB/ directories. SDC data calibration is a two-step process: raw data numbers from a particle impact are converted to a charge, and the charge is converted to a particle mass via the ground calibrations obtained at a dust acceleration facility. Refer to the provided documentation for more information Volume Format ============= This volume has been formatted according to the PDS Standards Reference 3.8 version current as of this data set's publication date. File Formats ============ All text documents and other meta information files such as descriptions, PDS object definitions and detached PDS labels are stream format files, with a carriage return (ASCII 13) and a line feed character (ASCII 10) at the end of the record. This allows the files to be read by most current operating systems. Data are provided in FITS format with detached PDS labels; the FITS files are the same as those generated by the NH Project data processing pipeline and used by the by NH instrument teams. Users comfortable with FITS format are welcome to use FITS libraries or other tools to parse and read the data directly from the FITS files; all others are advised to access the data through the lens of the detached PDS labels. See the Suggested FITS & PDS software PDS label overview sections below for approaches to reading the data. If the user does not have the skills and/or resources to read these data, they should contact the Planetary Data System (PDS) for support, or hire a competent programmer to further prepare the data for their use and analysis. Volume Contents =============== Files on this volume are organized into a set of subdirectories below the top-level directory. The following table shows the general structure and content of these directories, but does not exhaustively list every file in each directory. See the *INFO.TXT files in each top-level sub-directory for specific information about the files under that directory. In this table, directory names are surrounded by forward slashes (/), and the top-level of the volume is indicated by a single forward slash. Lines preceded with double-asterisks are not present in all data sets. / Top level of volume. | +-- AAREADME.TXT The AAREADME file; a backup is in /DOCUMENT/ **+-- ERRATA.TXT Description of any known errors or anomalies +-- VOLDESC.CAT Description of the logical contents of this volume. | +--/DOCUMENT/ Directory containing dataset-related documents. | +-- AAREADME_BU.TXT A backup of the top-level /AAREADME.TXT file | +-- DOCINFO.TXT Description of files in the DOCUMENT directory. | +-- *.* Documentation files | +--/SAMPLES/ Sub-directory containing data samples | +-- SAMPINFO.TXT Description of files in the SAMPLES dir. | +-- *.* Data sample files and documentation | |--/CATALOG/ Directory containing PDS catalog objects. | +-- CATINFO.TXT Description of files in the CATALOG directory. | +-- *.* Catalog files | +--/DATA/ Top-level data directory | +--/YYYYMMDD_SCRMET/ Sub-directories of /DATA/ containing data files | +-- *.* Data files | **+--/CALIB/ Top-level directory containing calibration files **| +-- CALINFO.TXT Description of files in the CALIB directory **| +-- *.* Calibration files | +--/INDEX/ Directory containing index files. | +-- INDXINFO.TXT Description of files in the INDEX directory +-- *.* Index files and labels Errata ====== The data in this data set are ideally certified with no known errors. Over time, errors may be brought to the attention of the NH Project and to PDS; such errors will be documented in file ERRATA.TXT in the top-level directory of this data set. Apparent anomalies and other oddities in the data, which are not in error, may be documented in ERRATA.TXT, and/or in the CONFIDENCE_LEVEL_NOTE of the data set catalog (CATALOG/DATASET.CAT), and/or in the Operational Considerations section of the instrument catalog SDC.CAT. Data Filenames and Product IDs ============================== The filenames of data files and the Product IDs of observations adhere to a common convention e.g. ALI_0123456789_0X0AB_ENG_1.FIT ^^^ ^^^^^^^^^^ ^^^^^ ^^^ ^\__/ | | | | | ^^ | | | | | | | | | | | +--File type (includes dot) | | | | | - .FIT for FITS file | | | | | - .LBL for PDS label | | | | | - not part of Product ID | | | | | | | | | +-- Version number; SOC-internal | | | | (Science Operations Center) | | | | (see Note FN1) | | | | | | | +--ENG for Raw data | | | SCI for Calibrated data | | | (see Note FN1) | | | | | +--Application ID (ApID) of the telemetry data | | packet from which the data come (see Note FN2) | | | +--Spacecraft Receipt Mission Elapsed Time (SCRMET) | +--Instrument/observation designator Note FN1: Version numbers are SOC-internal values; when looking for a calibrated version of a raw data file, the Instrument, SCRMET and ApID portion of the filenames will be the same between the raw and calibrated versions of the same observation, but the version numbers may differ. Note FN2: ApIDs may define the type of data taken by the instrument (e.g. mode) and the path taken by the data from the instrument to the ground (e.g. compression). Refer to the data set catalog, CATALOG/DATASET.CAT, and the SOC Instrument ICD for definitions of the ApIDs that may be present in this data set. Note that, depending on the observation, the SCRMET in the data filename and in the Product ID may be similar to the Mission Elapsed Time (MET) of the actual observation acquisition, but should not be used as an analog for the acquisition time. The SCRMET is the time that the data are transferred from the instrument to spacecraft memory and is therefore not a reliable indicator of the actual observation time. The PDS label and the index tables are better sources to use for the actual timing of any observation. The specific keywords and index table column names for which to look are * START_TIME * STOP_TIME * SPACECRAFT_CLOCK_START_COUNT * SPACECRAFT_CLOCK_STOP_COUNT Data directory naming convention ================================ All of the data files in this dataset are under, but not in, the top-level /DATA/ directory. Sub-directories, based on the SCRMET (see above) of the top-level /DATA/ directory have been provided to increase the granularity of data storage locations which in turn keeps there from being too many data files in any one directory. The granularity implemented is one sub-directory per 10,000 counts of the SCRMET (see Data Filenames and Product IDs section above). The subdirectory names on this volume reflect that granularity. These names are of the form YYYYMMDD_SCRMET/ where SCRMET is a grouping of the first six digits of the ten-digit SCRMET count, and YYYY, MM, and DD are the year, month and day of the first possible SCRMET corresponding to that six-digit SCRMET prefix. Any data file will be located in a directory whose six-digit SCRMET prefix matches that of the data file. Since each count represents about one second, there may be as many as nine six-digit SCRMET prefixes with the same YYYYMMDD values. Also, since days will not start or end exactly on 10,000 count SCRMET boundaries, directories with the naming convention may span day boundaries. That is, the YYYYMMDD value corresponding to the start of a 10,000 count SCRMET range may not be the same as the YYYYMMDD that corresponds to the end of that range. Explanation of granularity -------------------------- The granularity of sub-directories under /DATA/ on this volume has been copied from that used on the Science Operations Center (SOC) where the data files were originally generated. On the SOC, the same granularity was implemented across all eight New Horizons instruments' directory structures. Because the mission instruments generate data files at varying rates, from one or more data files per second to one or more days per data file, a compromise granularity of 10,000 SCRMET counts was chosen, and propagated to this volume. Suggested FITS & PDS software ============================= For working with PDS-labeled data, software packages are available at Planetary Data System (PDS) nodes (as of 2007). Several other options for reading either FITS or PDS-labeled data are listed here. If not included in the text below, references to the packages may be either found at one or more PDS nodes or found via a search engine. Data users planning to write custom software should refer to the PDS label description in the subtopics that follow for a general introduction and to the PDS Standards document available at PDS nodes. The following URLs were current as of 2007 when the early New Horizons data sets were delivered; given the availability of search engines for the World Wide Web, no attempt has been or will be made to update this information throughout the mission. Readers and viewers (Package name, format handled by it, and URL): READPDS PDS http://pdssbn.astro.umd.edu/nodehtml/software.shtml NASAVIEW PDS http://pds.nasa.gov/tools/software_download.cfm FV FITS http://heasarc.gsfc.nasa.gov/docs/software/ftools/fv/ DS9 FITS http://hea-www.harvard.edu/RD/ds9/ Development toolkits for IDL (http://www.ittvis.com/idl/): OAL PDS http://pds-rings.seti.org/toolkits/ ASTRO FITS http://idlastro.gsfc.nasa.gov/ Development toolkits for C & FORTRAN: OAL PDS http://pds-rings.seti.org/toolkits/ CFITSIO FITS http://heasarc.gsfc.nasa.gov/docs/software/fitsio/ Development toolkit for Python and Perl: PyFITS FITS http://www.stsci.edu/resources/software_hardware/pyfits/ CFITSIO.pm FITS http://hea-www.harvard.edu/~rpete/cfitsio/ General FITS info and many more references may be found at The FITS Support Office: http://fits.gsfc.nasa.gov/ N.B. The following description of PDS labels is only meant to be sufficient to write a program to read the FITS data files in this data set using the information contained in the corresponding detached PDS labels in this data set, and is therefore neither a complete nor PDS-sanctioned exposition of the PDS label format or PDS standards. For full details of the PDS standards, refer to the source from which this data set was obtained. PDS label overview ================== Under the DATA/ subdirectory of this data set, each PDS label file is a multi-record flat ASCII file describing the Data Units in a corresponding FITS data file that represent a single observation or group of observations. A FITS file is made up of one or more contiguous 2880-byte records. Each Data Unit (DU) in a FITS data file comprises one or more records. The data in each DU starts at the first byte of the DU and is arranged as described in the PDS label. If the data in a DU do not end at a 2880-byte boundary, then that DU is padded out to the boundary. Each record in a PDS label is 80 bytes long comprising 78 printable 7-bit ASCII characters and/or spaces and ending with a carriage return and a line feed. Most records are of the form KEYWORD = VALUE where KEYWORD is the name of a quantity, and VALUE represents the value of that quantity. Spaces before, after, and between the keyword, the equals sign, and the value(s) are not significant. String values may span multiple records, and are usually delimited by (i.e. enclosed in) double quotes. Strings contain no double quotes. Some string values, such as UTC times, are not enclosed in quotes. Most integer & floating point numeric values are displayed without quotes. Multiple values for a single keyword are indicated by enclosing the values in parentheses or curly braces and separating the values with commas. Comments are initiated by a contiguous forward-slash & asterisk pair (i.e. /*) on the left and continue to the end of a single record where they are usually terminated by a matching asterisk & forward-slash pair (*/). Whether or not the terminating pair is present, the comment ends at the end of the record, and another initiating pair must be present on the next record if that record is intended to continue the comment. Blank lines may be inserted between other lines to enhance readability. 1) PDS pointers Pointers are special cases of keyword/value pairs in the PDS label, and define where each DU starts in the FITS file; pointers look like this: ^HEADER = "XYZ.FIT" /* Primary Header DU (HDU) */ ^IMAGE = ("XYZ.FIT",11) /* Primary DU */ ^ERROR_HEADER = ("XYZ.FIT",22) /* Extension #1 HDU */ ^ERROR_IMAGE = ("XYZ.FIT",31) /* Extension #1 DU */ ^HOUSEKEEPING_HEADER = ("XYZ.FIT",43) /* Extension #2 HDU */ ^HOUSEKEEPING_TABLE = ("XYZ.FIT",44) /* Extension #2 DU */ ^THRUSTERS_HEADER = ("XYZ.FIT",45) /* Extension #3 HDU */ ^THRUSTERS_TABLE = ("XYZ.FIT",51) /* Extension #3 DU */ Pointer keywords HEADER and IMAGE refer to the Primary Header Data Unit (HDU) and Primary Data Unit, respectively. Pointer keywords that end in _HEADER refer to Extension HDUs. Pointer keywords that end in _IMAGE or _TABLE or _ARRAY refer to Extension DUs. The text after the equals sign in each pointer is usually enclosed by parentheses and comprises the filename of the file where the DU resides and the DU's location in that file. The filename and the location are delimited by a comma. The filename is a string enclosed in double quotes, and the DU location is a decimal integer value indicating the cardinal location in the file of the first 2880-byte record of the DU. For example, the ^IMAGE DU above, with a location value of 11, starts at an offset of 28800 bytes (= [11-1]*2880) from the first byte of the file. If only the filename is given, with neither the parentheses nor the comma nor the location, then the DU starts at the beginning of the file i.e. the location is implicitly set to one. 2) OBJECT stanzas Each pointer in a PDS label will have a corresponding OBJECT stanza. OBJECT stanzas comprise the lines between corresponding 'OBJECT=' & 'END_OBJECT=' keyword lines. OBJECT stanzas referring to TABLEs will contain one or more 'OBJECT=COLUMN'/'END_OBJECT=COLUMN' stanzas. See the comments (/* ... */) to the right of the keywords in the example below to understand the OBJECTs and keywords that describe binary tables. ************************************************************************ ********** N.B. This example does not describe every keyword ********** ********** that will be present in each table, but only ********** ********** those necessary to read and understand the ********** ********** arrangement of the data in the DU to which ********** ********** OBJECTs refer. Refer to the PDS standards ********** ********** for more details. ********** ********** Example starts after the next line ********** ************************************************************************ ^S_TABLE = ("XYZ.FIT",51) /* EDU #3; Data table */ OBJECT = S_TABLE /* Start of object describing data of pointer ^S_TABLE */ INTERCHANGE_FORMAT = BINARY ROWS = 463 /* Table comprises 463 rows */ COLUMNS = 97 /* Table comprises 97 columns */ ROW_BYTES = 1080 /* Each row comprises 1080 bytes */ DESCRIPTION = "..." OBJECT = COLUMN /* OBJECT describing column 1 */ NAME = STATUSES /* Column name */ COLUMN_NUMBER = 1 /* Column location within row */ DATA TYPE = MSB_INTEGER /* Column data element type */ ITEMS = 3 /* Number of data elements in column */ ITEM_BYTES = 2 /* Size of each data element in column */ START_BYTE = 1 /* Byte location in row of 1st byte of column */ BYTES = 6 /* Column width (bytes); <= ITEMS*ITEM_BYTES */ DESCRIPTION = "..." END_OBJECT = COLUMN OBJECT = COLUMN /* OBJECT describing column 2 */ NAME = TEMPERATURE /* Column name */ COLUMN_NUMBER = 2 /* Column location within row */ DATA TYPE = IEEE_REAL /* Column data type */ ITEMS = 1 /* Number of data elements in column */ ITEM_BYTES = 4 /* Size of each data element in column */ START_BYTE = 7 /* Byte location in row of 1st byte of column */ BYTES = 4 /* Column width (bytes); <= ITEMS * ITEM_BYTES */ DESCRIPTION = "..." END_OBJECT = COLUMN ... END_OBJECT = S_TABLE /* End of object S_TABLE */ ************************************************************************ ********** Example ends before the previous line ***************** ************************************************************************ In the example above: - the table S_TABLE starts at byte 144001 ((51-1)*2880 + 1) of the file, and comprises 97 rows each of width 1080 bytes. - the first column, named STATUSES, in each row starts at the 1st byte of that row and comprises three MSB-first 16-bit integers using 6 bytes total on each row. - the second column, named TEMPERATURE, in each row starts at the seventh byte of that row and comprises one IEEE 32-bit floating point value using four bytes total on each row. - Subsequent rows are offset 1080 bytes from the previous row. Generic PDS label details ========================= The PDS label has meta-data which describe the circumstances surrounding the data in the FITS file. These meta-data are in keyword and value pairs (e.g. the pointers above) and each of these keywords is described in the PDS Data Dictionary plus the New Horizons mission- specific local data dictionary supplemental items, both of which are available in this archive. All FITS Header Data Units (HDUs) and Data Units are described in the PDS labels. In some cases, no Data Unit will be described in the PDS label because there is nothing to describe i.e. it is not present in the FITS file. PDS LABELS: Column Descriptions in binary tables ------------------------------------------------- FITS extensions may contain data that are a subset of instrument and/or spacecraft housekeeping telemetry packets formatted as binary tables. Where possible, each column included in such extensions has a DESCRIPTION field something like this: DESCRIPTION = " Full Mnemonic: SWAP_RT.SEC64_ST General Description: A bit indicating the beginning of a 64-second cycle Conversion: STATES - [lo:hi]=state description: [0:0]=CONT [1:1]=START Subsystem: SWAP Packet ApID: 0X584 Byte Offset within ApID packet: 10 Bit Offset within Byte of ApID packet: 0 Bit Length within ApID packet: 1 Type of value: UNSIGNED Units: N/A " The sub-fields used in these DESCRIPTION fields are as follows: Full Mnemonic: The complete mnemonic used in the definition of the packet. The COLUMN name will typically be a subset of this mnemonic. General Description: A description of the column Extended Description: More information - this field is not always present Conversion: This item describes the conversion of the value found in the column to a meaningful quantity. It takes one of two forms: STATES and polynomial. If the conversion form is STATES, then the bits of the column are combined into an integer and compared against the ranges list. In the example above, if the value of the bit is zero, then the SWAP_RT.SEC64T column represents a continuing state. If the value of the bit is 1, then the SWAP_RT_SEC64T column indicates that a new 64-second cycle has just begun. If the conversion form is polynomial, then the bits of the column are combined into an integer and used as the independent value of the polynomial with the coefficients given. For example, if the integer value of a column is 100, and its conversion looks like this: Conversion: polynomial coefficients: Order 0: 0.925 Order 1: 0.979 Then the derived value of this instrument is 0.925 + (0.979 * 100) = 98.825 Subsystem: Which subsystem generated the packet Packet ApID: The Application ID of the packet Byte & Bit Offsets & Bit Length: the location of the column's value in the packet, including the 10-byte CCDS header. Type of value: For integer values, whether the value is signed or unsigned Units: Nominal units of the derived column values Whom to Contact for Information =============================== New Horizons SDC Principal Investigator: Mihaly Horany, LASP, University of Colorado Mihaly Horanyi Laboratory for Atmospheric and Space Physics University of Colorado Boulder, CO 80302-0392 USA New Horizons Science Operation Center (SOC): Joe Peterson Southwest Research Institute (SWRI) Department of Space Studies 1050 Walnut Street, Suite 400 Boulder, CO 80302 USA