The GRAIL SPICE Data Archive ======================================================================== Introduction ============ This document provides an overview of the GRAIL SPICE data set, including a description of the directory structure. Additional documents included on this data set provide more details, especially the ``spiceds.cat'' dataset description and the various kernel-specific ``/data/*/*info.txt'' files. This data set contains navigation and related observation geometry and other ancillary data in the form of SPICE System kernel files for the GRAIL spacecraft. See the file ``mission.cat'' in the ``/catalog'' directory for a description of the mission and the files ``insthost_a.cat'' and ``insthost_b.cat'' in the same directory for a description of the spacecraft. The SPICE kernel files contain geometric and other ancillary information needed to recover the full value of science instrument data. Data in the SPICE kernel files must be accessed using the NAIF (Navigation and Ancillary Information Facility) software called the SPICE Toolkit. See the file ``softinfo.txt'' in the ``/software'' directory for instructions on how to obtain this software. This data set is contained on a single virtual volume, GRLSP_1000, including data from all mission phases and covering from launch, 2011 SEP 10, through the end time of the latest spacecraft trajectory file supplied in the data set. Until the end of the spacecraft lifespan this data set will be accumulating with new data added according to the project archiving plan. 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 MS-DOS/Windows, Unix and MacOS operating systems. The data files in this data set were prepared to be used under a UNIX environment. Therefore all SPICE text kernel files are UNIX text files, with a line feed character (ASCII 10) at the end of the line, and all SPICE binary kernels files are UNIX binary files in which bit pattern structures for double precision and integer numbers follow the IEEE standard. While some of the data files on this volume can be used 'as is', converting the files to binary or text format native to the user's computer may be required. Refer to the documentation provided with the SPICE Toolkit to find out whether conversion is needed in each specific case. NAIF provides a tool (BINGO) that can convert either binary or text kernels from one format to another. This means that text files can have their line terminator changed and binary files can be converted to the native format of the platform of interest. For access to this tool, see the reference to the NAIF utilities website in the file ``/software/softinfo.txt''. Volume Contents =============== Files on this volume are organized into a set of subdirectories below the top-level directory. The following table shows the structure and content of these directories. In this table, directory names are enclosed in square brackets (). See the ``*info.txt'' files in each directory for specific information on the files in the directory, including naming schemes. [top-level-directory] | |-- aareadme.txt Text version of the aareadme file. |-- aareadme.htm HTML version of the aareadme file. |-- aareadme.lbl PDS label for both aareadme files. |-- errata.txt Comments and errata on this volume. |-- voldesc.cat Description of the contents of this volume. | |--[catalog] Directory containing PDS catalog objects. | | | |-- catinfo.txt Description of files in the catalog directory. | |-- insthost_a.cat Description of the GRAIL-A spacecraft. | |-- insthost_b.cat Description of the GRAIL-B spacecraft. | |-- insthost.cat Description of the spacecraft. | |-- mission.cat Description of the mission. | |-- person.cat References for personnel who created this volume. | |-- ref.cat List of publications mentioned in *.cat files. | |-- release.cat Description of the data set releases. | |-- spiceds.cat Description of the SPICE data set. | |-- spice_hsk.cat Description of housekeeping (browser) information. | +-- spice_inst.cat Description of SPICE kernels. | |--[data] Directory containing SPICE data files (kernels.) | | | |--[ck] Directory containing CK files. | | | | | |-- ckinfo.txt Description of files in the data/ck directory. | | |-- *.bc CK files. | | +-- *.lbl PDS labels for CK files. | | | |--[ek] Directory containing EK files. | | | | | +-- ekinfo.txt Description of files in the data/ek directory. | | | |--[fk] Directory containing FK file(s). | | | | | |-- fkinfo.txt Description of files in the data/fk directory. | | |-- *.tf FK file(s). | | +-- *.lbl PDS labels for FK files. | | | |--[ik] Directory containing IK files. | | | | | |-- ikinfo.txt Description of files in the data/ik directory. | | |-- *.ti IK files. | | +-- *.lbl PDS labels for IK files. | | | |--[lsk] Directory containing LSK files. | | | | | |-- lskinfo.txt Description of files in the data/lsk directory. | | |-- *.tls LSK file(s). | | +-- *.lbl PDS labels for LSK files. | | | |--[pck] Directory containing PCK file(s). | | | | | |-- pckinfo.txt Description of files in the data/pck directory. | | |-- *.tpc Text PCK file(s). | | |-- *.bpc Binary PCK file(s). | | +-- *.lbl PDS labels for PCK files. | | | |--[sclk] Directory containing SCLK file(s). | | | | | |-- sclkinfo.txt Description of files in the data/sclk directory. | | |-- *.tsc SCLK file(s). | | +-- *.lbl PDS labels for SCLK files. | | | +--[spk] Directory containing SPK files. | | | |-- spkinfo.txt Description of files in the data/spk directory. | |-- *.bsp SPK files. | +-- *.lbl PDS labels for SPK files. | |--[document] Directory containing volume related documents. | | | |-- docinfo.txt Description of files in the document directory. | |-- onlabels.txt Description of PDS labels for SPICE kernels. | +-- lblinfo.txt Description of PDS label location in this volume. | |--[extras] Directory containing extra data elements. | | | |-- extrinfo.txt Description of files and directories in extras. | | | |--[mk] Directory containing meta-kernels. | | | | | |-- mkinfo.txt Description of meta-kernel files. | | +-- *.tm Meta-kernel files. | | | +--[orbnum] Directory containing orbit number files. | | | |-- orbinfo.txt Description of orbit number files. | +-- *.nrb ``node-to-node'' orbit number files. | |--[index] Directory containing index files. | | | |-- indxinfo.txt Description of files in the index directory. | |-- checksum.tab Table of MD5 checksums for files in this data set. | |-- checksum.lbl PDS label for checksum.tab file. | |-- index.tab Index table of SPICE kernels on this volume. | +-- index.lbl PDS label for index.tab file. | +--[software] | +-- softinfo.txt instructions on how to obtain SPICE software. Whom to Contact for Information =============================== PDS Navigation and Ancillary Information Facility (NAIF), MAIL STOP 301-121 Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive Pasadena, CA, 91109-8099 818-354-8136 WWW Site: http://naif.jpl.nasa.gov Electronic mail address: email@example.com Cognizant Persons ================= This volume was produced by Boris Semenov, Planetary Data System Navigation and Ancillary Information Facility Node, Jet Propulsion Laboratory, Pasadena, California.