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Grail Data Product Software Interface Specification Jpl D-76383

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Grail Data Product Software Interface Specification Jpl D-76383 GRAIL DATA PRODUCT SOFTWARE INTERFACE SPECIFICATION JPL D-76383 Version 1.8 May 3, 2016 Daniel Kahan Copyright 2013 California Institute of Technology. Government sponsorship acknowledged. Copyright 2013. All rights reserved. GRAIL DATA PRODUCT SOFTWARE INTERFACE SPECIFICATION TABLE OF CONTENTS TABLES 5 DOCUMENT CHANGE LOG ....................................................................................................................... 7 1 Purpose and Scope of Document ........................................................................................................... 8 2 Definitions of Data Processing Levels ................................................................................................... 9 3 Relationships with Other Interfaces ....................................................................................................... 9 4 Data Product Characteristics and Environment ...................................................................................... 9 4.1 Instrument Overview ..................................................................................................................................9 4.2 Data Product Overview ........................................................................................................................... 11 4.2.1 LGRS EDR (NASA Level 0 Products) ............................................................. 11 4.2.2 LGRS CDR (NASA Level 1A and Level 1B Products) .................................... 12 4.2.2.1 Timing [17] .................................................................................................................................. 12 4.2.2.2 Position ........................................................................................................................................ 13 4.2.2.3 Ka-band ....................................................................................................................................... 14 4.2.2.4 S-band .......................................................................................................................................... 14 4.2.2.5 Satellite Attitude .......................................................................................................................... 14 4.2.2.6 Events .......................................................................................................................................... 15 4.2.2.7 Satellite Condition ....................................................................................................................... 15 4.2.2.8 DSN Tracking .............................................................................................................................. 15 4.2.3 RSS EDR ........................................................................................................... 15 4.2.3.1 DSN Radio Data .......................................................................................................................... 15 4.2.3.2 Ancillary DSN Data..................................................................................................................... 16 4.2.4 LGRS RDR (NASA Level 2 Products) ............................................................. 17 4.2.5 Data Flow and Product Generation ................................................................... 17 4.2.6 Labeling and Identification ................................................................................ 18 4.2.6.1 LGRS EDR and LGRS CDR File Naming Convention .............................................................. 18 4.2.6.2 RSS EDR File Naming Convention ............................................................................................ 19 4.2.6.3 LGRS RDR File Naming Convention ......................................................................................... 20 4.3 Standards Used in Generating Data Products .......................................................................................... 22 4.3.1 PDS Standards ................................................................................................... 22 4.3.2 Time Standards .................................................................................................. 22 4.3.2.1 LGRS clock ................................................................................................................................. 23 4.3.2.2 Onboard spacecraft clocks ........................................................................................................... 23 4.3.2.3 UTC clock used by DSN ............................................................................................................. 23 2 GRAIL DATA PRODUCT SOFTWARE INTERFACE SPECIFICATION 4.3.3 Coordinate Systems ........................................................................................... 24 4.4 Data Validation ........................................................................................................................................ 27 5 Detailed Data Product Specifications ................................................................................................... 27 5.1 Data Product Structure and Organization ................................................................................................ 27 5.2 Data Format Descriptions ........................................................................................................................ 31 5.2.1 LGRS EDR (Level 0) Products ......................................................................... 31 5.2.2 LGRS CDR Products ......................................................................................... 34 5.2.2.1 Level 1A ...................................................................................................................................... 34 5.2.2.2 Level 1B ...................................................................................................................................... 48 5.2.3 RSS EDR Products ............................................................................................ 56 5.3 Header Descriptions ................................................................................................................................ 57 5.3.1 Headers for LGRS EDR .................................................................................... 57 5.3.2 Headers for LGRS CDR .................................................................................... 57 5.3.3 Headers for LGRS RDR .................................................................................... 58 5.3.4 Headers for RSS EDR ....................................................................................... 58 6 Applicable Software ............................................................................................................................. 59 6.1 Utility Programs ...................................................................................................................................... 59 7 Appendices ........................................................................................................................................... 59 7.1 Glossary ................................................................................................................................................... 59 7.2 Acronyms ................................................................................................................................................ 60 7.3 Example PDS Labels ............................................................................................................................... 62 7.3.1 LGRS EDR ........................................................................................................ 62 7.3.2 LGRS CDR ........................................................................................................ 62 7.3.3 RSS EDR ........................................................................................................... 63 7.3.3.1 BTM, EOP, ION, TDM, TNF, TRO, WEA, & XFR ................................................................... 63 7.3.3.2 ODF, OLF, and BOF ................................................................................................................... 64 7.3.3.3 RSR.............................................................................................................................................. 92 7.3.4 LGRS RDR ...................................................................................................... 113 7.3.4.1 Radio Science Digital Map Products (RSDMAP) ..................................................................... 113 7.3.4.2 Spherical Harmonics ASCII Data Record (SHADR) ................................................................ 114 7.3.4.3 Spherical Harmonics Binary Data Record (SHBDR) ................................................................ 119 7.3.4.4 SPICE ephemeris files (SPK) .................................................................................................... 124 8 Applicable Documents ....................................................................................................................... 124 3 GRAIL DATA PRODUCT SOFTWARE INTERFACE SPECIFICATION FIGURES Figure 1: View of GRAIL satellites .............................................................................................................. 10 Figure 2: Payload Block Diagram [26] ........................................................................................................
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