PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = " For New horizons, this LABEL_REVISION_NOTE is used to keep track of when the template is used to generate a DATASET.CAT file for a data set. Brian Carcich - Publication date: 2014-11-13 - NH-internal archive software version: V2.0 " RECORD_TYPE = STREAM INSTRUMENT_HOST_NAME = "NEW HORIZONS" OBJECT = DATA_SET DATA_SET_ID = "NH-X-SWAP-2-PLUTOCRUISE-V2.0" OBJECT = DATA_SET_INFORMATION START_TIME = 2008-05-28T22:03:46.554 STOP_TIME = 2014-08-18T02:47:29.538 DATA_SET_DESC = " Data Set Overview ================= This data set contains Raw data taken by New Horizons Solar Wind Around Pluto instrument during the PLUTOCRUISE mission phase. SWAP comprises electro-optics and detectors to obtain count rate measurements of the the solar wind; measuring the solar wind before, during and after the Pluto encounter will allow characterization of the atmospheric escape rate of Pluto. The SWAP electro-optic elements select the angles and energies of the solar wind and pickup ions to be measured; ions thus selected are registered with a coincidence detector system. SWAP measures the energy spectrum of ions in its environment by varying (also called scanning or sweeping) voltages of the electro-optics over many steps during a short time period. SWAP can also immediately follow a sweep of coarse voltage steps with a sweep of finer steps, centered on the peak measurement of the coarse sweep, to obtain a higher resolution of that portion of the energy spectrum. There are three types of SWAP science data: real-time; summary; histogram. Real-time data, at rates up to 1Hz, provide the most detailed science measurements since they contain the full count rate distribution as a function of energy (speed). For science summary and science histogram modes, the full distribution is not recorded. Instead, parameters are derived from the count rate distribution stored by SWAP. These derived parameters require less memory than storing the whole distribution. The science summary and science histogram modes are primarily used during the cruise phase of the mission. For science data, the common data product is usually a binary table; for calibrated real-time data, spectrograms as images are also provided. Typically the tables have instrument parameters and measurements in the columns and measurement times in the rows, but the actual format depends on the type of data and the processing level (raw vs. calibrated). Other tables containing houskeeping and other parameters are also provided. This data set includes documentation for all data types and formats. Per the original mission plan for cruise operations, the SWAP instrument was off for the first 460+ days of Pluto Cruise. After that the operations were sporadic (just a few days in 2009) and mostly Science, alternating with Channel Electron Multiplier gain tests during Annual CheckOuts. After extensive testing in early 2012, in July of that year the project approved daily science operations for the SWAP and PEPSSI instruments throughout the rest of the cruise to Pluto. Every observation provided in this data set was taken as a part of a particular sequence. A list of these sequences has been provided in file DOCUMENT/SEQ_SWAP_PLUTOCRUISE.TAB. N.B. Some sequences provided may have no corresponding observations. For a list of observations, refer to the data set index table; this is typically INDEX.TAB initially in the INDEX/ area of the data set; there is also a file SLIMINDX.TAB in INDEX/ that summarizes key information relevant to each observation, including which sequence was in effect and what target was likely intended for the observation. Version ======= This is VERSION 2.0 of this data set. The pipeline (see Processing below) was re-run on these data for each version since the first (V1.0). As a result, ancillary information, such as observational geometry and time (SPICE), may be updated. This will affect, for example, the calibration of the data if parameters such as the velocity or orientation of the target relative to the instrument, or the recorded target itself, have changed. See the following sections for details of what has changed over each version since the first (V1.0). Note that even if this is not a calibrated data set, the calibration changes are listed as the data will have been re-run and there will be updates to the calibration files, to the documentation and to the steps required to calibrate the data. SWAP updates for Pluto Cruise Data Sets V2.0 ============================================ Added over 2200 DATA/ files from Annual CheckOuts 5-8 (ACO5-8), plus cruise and hibernation observations, from approximately mid-2010 through late 2014. The initial version of this data set contained data only through mid-2010. About two-thirds of the products from V1.0 have been redelivered with changed PRODUCT_IDs and new filenames; the data in those products will not have changed significantly if at all. A table listing the new names in V2.0 and the corresponding old names from V1.0 has been provided in the DOCUMENT/ subdirectory of this data set; refer to the PDS label of that TABLE for more details. These changes are due to modifications made to the file naming algorithms in the source data processing pipeline software in the Science Operations Center (SOC). Processing ========== The data in this data set were created by a software data processing pipeline on the Science Operation Center (SOC) at the Southwest Research Institute (SwRI), Department of Space Studies. This SOC pipeline assembled data as FITS files from raw telemetry packets sent down by the spacecraft and populated the data labels with housekeeping and engineering values, and computed geometry parameters using SPICE kernels. The pipeline did not resample the data. Data ==== The observations in this data set are stored in data files using standard Flexible Image Transport System (FITS) format. Each FITS file has a corresponding detached PDS label file, named according to a common convention. The FITS files may have image and/or table extensions; see the PDS label plus the DOCUMENT files for a description of these extensions and their contents. This Data section comprises the following sub-topics: - Filename/Product IDs - Instrument description - Other sources of information useful in interpreting these Data - Visit Description, Visit Number, and Target in the Data Labels Filename/Product IDs -------------------- The filenames and 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 from the SOC | | | | (Science Operations Center) | | | | | | | +--ENG for CODMAC Level 2 data * | | | SCI for CODMAC Level 3 data * | | | | | +--Application ID (ApID) of the telemetry data | | packet from which the data come | | | +--MET (Mission Event Time) i.e. Spacecraft Clock | +--Instrument designator * For those datasets where the NH project is delivering CODMAC Level 1 & 2 data (REX & PEPSSI), ENG and SCI apply to CODMAC Level 1 & 2 data, respectively. Instrument Instrument designators ApIDs =========== ================================== ============= SWAP SWA 0X584 - 0X587 * * Not all values in this range are in this data set There are other ApIDs that contain housekeeping values and other values. See the documentation for more details. Here is a summary of the types of files generated by each ApID along with the instrument designator that go with each ApID: ApIDs Data product description/Prefix(es) ===== =================================== 0x584 - SWAP Science Real-Time/SDC 0x585 - SWAP Science Summary/SWA 0x586 - SWAP Science Histogram Header/SWA 0x587 - SWAP Science Histogram Data/SWA Instrument description ---------------------- Refer to the following files for a description of this instrument. CATALOG SWAP.CAT DOCUMENTS SWAP_SSR.* SOC_INST_ICD.* NH_SWAP_V###_TI.TXT (### is a version number) Other sources of information useful in interpreting these Data -------------------------------------------------------------- Refer to the following files for more information about these data NH Trajectory tables: /DOCUMENT/NH_MISSION_TRAJECTORY.* - Heliocentric SWAP Field Of View definitions: /DOCUMENT/NH_FOV.* /DOCUMENT/NH_SWAP_V###_TI.TXT SWAP Data summary plots: /DOCUMENT/DATA_SUMMARY_PLOTS/SWAP_###DAY_YYYYMMDDHH_#.* Visit Description, Visit Number, and Target in the Data Labels --------------------------------------------------------------- The observation sequences were defined in Science Activity Planning (SAP) documents, and grouped by Visit Description and Visit Number. The SAPs are spreadsheets with one Visit Description & Number per row. A nominal target is also included on each row and included in the data labels, but does not always match with the TARGET_NAME field's value in the data labels. In some cases, the target was designated as RA,DEC pointing values in the form ``RADEC=123.45,-12.34'' indicating Right Ascension and Declination, in degrees, of the target from the spacecraft in the Earth Equatorial J2000 inertial reference frame. This indicates either that the target was either a star, or that the target's ephemeris was not loaded into the spacecraft's attitude and control system which in turn meant the spacecraft could not be pointed at the target by a body identifier and an inertial pointing value had to be specified as Right Ascension and Declination values. The PDS standards do not allow putting a value like RADEC=... in the PDS TARGET_NAME keyword's value; in those cases the PDS TARGET_NAME value is set to CALIBRATION. Ancillary Data ============== The geometry items included in the data labels were computed using the SPICE kernels archived in the New Horizons SPICE data set, NH-X-SPICE-6-PLUTOCRUISE-V1.0. Every observation provided in this data set was taken as a part of a particular sequence. A list of these sequences has been provided in file DOCUMENT/SEQ_SWAP_PLUTOCRUISE.TAB. In addition, the sequence identifier (ID) and description are included in the PDS label for every observation. N.B. While every observation has an associated sequence, every sequence may not have associated observations; that is, some sequences may have failed to execute due to spacecraft events (e.g. safing) and there will be observations associated with those sequences. No attempt has been made during the preparation of this data set to identify if any, or how many, such empty sequences there are, so it is up to the user to compare the times of the sequences to the times of the available observations from the INDEX/INDEX.TAB table to identify such sequences. Time ==== There are several time systems, or units, in use in this dataset: New Horizons spacecraft MET (Mission Event Time or Mission Elapsed Time), UTC (Coordinated Universal Time), and TDB Barycentric Dynamical Time. This section will give a summary description of the relationship between these time systems. For a complete explanation of these time systems the reader is referred to the documentation distributed with the Navigation and Ancillary Information Facility (NAIF) SPICE toolkit from the PDS NAIF node, (see http://naif.jpl.nasa.gov/). The most common time unit associated with the data is the spacecraft MET. MET is a 32-bit counter on the New Horizons spacecraft that runs at a rate of about one increment per second starting from a value of zero at 19.January, 2006 18:08:02 UTC or JD2453755.256337 TDB. The leapsecond adjustment (DELTA_ET = ET - UTC) over this dataset is 65.184s. The data labels for any given product in this dataset usually contain at least one pair of common UTC and MET representations of the time at the middle of the observation. Other portions of the products, for example tables of data taken over periods of up to a day or more, will only have the MET time associated with a given row of the table. For the data user's use in interpreting these times, a reasonable approximation (+/- 1s) of the conversion between Julian Day (TDB) and MET is as follows: JD TDB = 2453755.256337 + ( MET / 86399.9998693 ) For more accurate calculations the reader is referred to the NAIF/SPICE documentation as mentioned above. Reference Frame =============== Geometric Parameter Reference Frame ----------------------------------- Earth Mean Equator and Vernal Equinox of J2000 (EMEJ2000) is the inertial reference frame used to specify observational geometry items provided in the data labels. Geometric parameters are based on best available SPICE data at time of data creation. Epoch of Geometric Parameters ----------------------------- All geometric parameters provided in the data labels were computed at the epoch midway between the START_TIME and STOP_TIME label fields. Software ======== The observations in this data set are in standard FITS format with PDS labels, and can be viewed by a number of PDS-provided and commercial programs. For this reason no special software is provided with this data set. Contact Information =================== For any questions regarding the data format of the archive, contact New Horizons SWAP Principal Investigator: David McComas, Southwest Research Institute David McComas Southwest Research Institute Space Science and Engineering P.O. Drawer 28510 San Antonio, TX 78228-0510 USA " CONFIDENCE_LEVEL_NOTE = " Confidence Level Overview ========================= During the processing of the data in preparation for delivery with this volume, the packet data associated with each observation were used only if they passed a rigorous verification process including standard checksums. In addition, raw (Level 2) observation data for which adequate contemporary housekeeping and other ancillary data are not available may not be reduced to calibrated (Level 3) data. This issue is raised here to explain why some data products in the raw data set, NH-X-SWAP-2-PLUTOCRUISE-V2.0, may not have corresponding data products in the calibrated data set, NH-X-SWAP-3-PLUTOCRUISE-V2.0. Data coverage and quality ========================= Every observation provided in this data set was taken as a part of a particular sequence. A list of these sequences has been provided in file DOCUMENT/SEQ_SWAP_PLUTOCRUISE.TAB. N.B. Some sequences provided may have zero corresponding observations. Refer to the Confidence Level Overview section above for a summary of steps taken to assure data quality. Caveat about TARGET_NAME in PDS labels and observational intent =============================================================== A fundamental truth of managing data from some spacecraft missions is that the intent of any observation is not suitable for insertion into the command stream sent to the spacecraft to execute that observation. As a result, re-attaching that intent to the data that are later downlinked is problematic at best; for New Horizons that task is made even more difficult as the only meta-data that come down with the observation is the unpredictable time of the observation. The task is made yet even more difficult because uplink personnel, who generate the command sequences and initially know the intent of each observation, are perpetually under deadlines imposed by orbital mechanics and can rarely be spared for the time-intensive task of resolving this issue. To make a long story short, the downlink team on New Horizons has created an automated system to take various uplink products, decode things like Chebyshev polynomials in command sequences representing celestial body ephemerides for use on the spacecraft to control pointing, and infer from those data what the most likely intended target was at any time during the mission. This works well during flyby encounters and less so during cruise phases and hibernation. The point to be made is that the user of these PDS data needs to be cautious when using the TARGET_NAME and other target-related parameters stored in this data set. This is less an issue for the plasma and particle instruments, more so for pointing instruments. To this end, the heliocentric ephemeris of the spacecraft, the spacecraft-relative ephemeris of the inferred target, and the inertial attitude of the instrument reference frame are provided with all data, in the J2000 inertial reference frame, so the user can check where that target is in the Field Of View (FOV) of the instrument. Furthermore, for pointing instruments with one or more spatial components to their detectors, a table has been provided in the DOCUMENT/ area with XY (two-dimensional) positions of each inferred target in the primary data products; if those values are several thousand pixels off of a detector array, it is a strong indication that the actual target of that observation is something other than the inferred target, or no target at all e.g. dark sky. Review ====== This dataset was peer reviewed and certified for scientific use on TBD. " ABSTRACT_DESC = " This data set contains Raw data taken by the New Horizons Solar Wind Around Pluto instrument during the pluto cruise mission phase. This is VERSION 2.0 of this data set. This is Version 2.0 of this data set and supersedes Version 1.0. It contains over 2200 additional observations from late 2010 through late 2014 not included in Version 1.0; it also renamed some of the observations from Version 1.0. " CITATION_DESC = " McComas, D., NEW HORIZONS Raw SWAP PLUTO CRUISE V2.0, NH-X-SWAP-2-PLUTOCRUISE-V2.0, NASA Planetary Data System, 2014. " DATA_OBJECT_TYPE = "TABLE" DATA_SET_COLLECTION_MEMBER_FLG = "N" DATA_SET_NAME = "NEW HORIZONS SWAP PLUTO CRUISE RAW V2.0" DATA_SET_RELEASE_DATE = 2014-11-13 DATA_SET_TERSE_DESC = " Raw data taken by New Horizons Solar Wind Around Pluto instrument during the PLUTOCRUISE mission phase. This is VERSION 2.0 of this data set. " DETAILED_CATALOG_FLAG = "N" PRODUCER_FULL_NAME = "JOSEPH PETERSON" END_OBJECT = DATA_SET_INFORMATION OBJECT = DATA_SET_MISSION MISSION_NAME = "NEW HORIZONS" END_OBJECT = DATA_SET_MISSION OBJECT = DATA_SET_REFERENCE_INFORMATION REFERENCE_KEY_ID = "N/A" END_OBJECT = DATA_SET_REFERENCE_INFORMATION OBJECT = DATA_SET_TARGET TARGET_NAME = "SOLAR WIND" END_OBJECT = DATA_SET_TARGET OBJECT = DATA_SET_HOST INSTRUMENT_HOST_ID = "NH" INSTRUMENT_ID = "SWAP" END_OBJECT = DATA_SET_HOST END_OBJECT = DATA_SET END