PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 80 OBJECT = TEXT PUBLICATION_DATE = 1999-11-11 NOTE = "Software Interface Specification for the Line of Sight Acceleration Profile Data Record (LOSAPDR). Formatted for display or printing at 58 lines per page with up to 78 constant width characters per line." END_OBJECT = TEXT END SOFTWARE INTERFACE SPECIFICATION LINE OF SIGHT ACCELERATION PROFILE DATA RECORD prepared by Richard A. Simpson Packard Bldg -- Room 332 Stanford University Stanford, CA 94305-9515 Version 2.0.1 11 November 1999 PREFACE |============================================================================| | | | DOCUMENT CHANGE LOG | | | |============================================================================| |REVISION|REVISION| SECTION | REMARKS | | NUMBER | DATE | AFFECTED | | |--------+--------+------------+---------------------------------------------| | 2.0 |99/06/11| All |Adapted from LOSAPDR SIS V1.13.2, which was | | | | | written for Magellan and Mars Observer. | | | | | V2.0 focuses on Mars Global Surveyor and | | | | | Lunar Prospector. The document itself is | | | | | significantly streamlined; details of the | | | | | product definition are in the PDS label. | | | | | The LOSAPDR itself has not changed much. | | | | | There is a new file naming convention, there| | | | | are detached rather than attached labels, | | | | | and keywords FILE_NAME and LABEL_RECORDS | | | | | have been dropped from the label. The | | | | | structure of the data file is identical to | | | | | the structure used for Magellan data. | |--------+--------+------------+---------------------------------------------| | 2.0.1 |99/11/11| 1.4.5 |Removed non-printing ASCII character | |--------+--------+------------+---------------------------------------------| | 2.0.1 |99/11/11| Cover |Updated address for Simpson | |--------+--------+------------+---------------------------------------------| | 2.0.1 |99/11/11|Distribution|Added: D.-N. Yuan, J. Wilf, S. Joy, L. Huber,| | | | | and E.Guinness | | | | |Removed: V. Henderson, R.J. Phillips | | | | |Update: Arvidson, Rappaport | |========|========|============|=============================================| |============================================================================| | | | ITEMS TO BE DETERMINED | | | |============================================================================| | REVISION | SECTION | ITEM DESCRIPTION | RESOLUTION | | NUMBER | AFFECTED | | | |----------+----------+--------------------------------+---------------------| | | | | | |==========|==========|================================|=====================| DISTRIBUTION JPL/Gravity ----------- W. Sjogren..............301-150G wls@kamel.jpl.nasa.gov A. Konopliv.............301-130G ask@krait.jpl.nasa.gov T.C. Wang...............301-275R tcw@zeus.jpl.nasa.gov R. Wimberly.............301-155N wimberly@pop.jpl.nasa.gov N. Rappaport............301-280 rappapor@pop.jpl.nasa.gov D.-N. Yuan..............301-125J dny@krait.jpl.nasa.gov JPL/Mars Global Surveyor ------------------------ T. Thorpe............JPL 264-214 tthorpe@jpl.nasa.gov R. Springer..........JPL 264-214 rspringe@pop.jpl.nasa.gov Washington University --------------------- R.E. Arvidson.....Earth/Plan Sci arvidson@wunder.wustl.edu E. Guinness.......Earth/Plan Sci guinness@wunder.wustl.edu J. Alexopoulos....Earth/Plan Sci jim@wuzzy.wustl.edu Mars Global Surveyor Radio Science ---------------------------------- G.L. Tyler..............Stanford len@nova.stanford.edu D.E. Smith.........GSFC Code 920 dsmith@tharsis.gsfc.nasa.gov G. Balmino..................CNES gbalmino@pontos.cnes.fr P. Priest............JPL 264-860 trish@rodan.jpl.nasa.gov New Mexico State University --------------------------- L. Huber..........Dept Astronomy lhuber@nmsu.edu UCLA ---- S. Joy.........IGPP/6707 Geology sjoy@igpp.ucla.edu PDS ------- J. Wilf..............JPL 171-264 joel.wilf@jpl.nasa.gov CONTENTS Preface Document Change Log Items to be Determined Distribution Contents Acronyms and Abbreviations 1. General Description 1.1. Overview 1.2. Scope 1.3. Applicable Documents 1.4. Functional Description 1.4.1. Interface Location and Medium 1.4.2. Data Sources, Transfer Methods, and Destinations 1.4.3. Generation Method and Frequency 1.4.4. Pertinent Relationships with Other Interfaces 1.4.5. Labeling and Identification 1.5. Assumptions and Constraints 1.5.1. Usage Constraints 1.5.2. Priority Phasing Constraints 1.5.3. Explicit and Derived Constraints 1.5.4. Documentation Conventions 1.5.4.1. Data Format Descriptions 1.5.4.2. Time Standards 1.5.4.3. Coordinate Systems 1.5.4.4. Limits of This Document 1.5.4.5. Typographic Conventions 2. Interface Characteristics 2.1. Hardware Characteristics and Limitations 2.1.1. Special Equipment and Device Interfaces 2.1.2. Special Setup Requirements 2.2. Volume and Size 2.3. Interface Medium Characteristics 2.4. Failure Protection, Detection, and Recovery Procedures 2.5. End-of-File Conventions 2.6. End-of-Volume Conventions 3. Access 3.1. Programs Using the Interface 3.2. Synchronization Considerations 3.2.1. Timing and Sequencing Considerations 3.2.2. Effective Duration 3.2.3. Priority Interrupts 3.3. Input/Output Protocols, Calling Sequences 4. Detailed Interface Specifications 4.1. Structure and Organization Overview 4.2. PDS Label 4.2.1. Keyword-Value Pairs 4.2.2. Object Definitions 4.3. Data File 4.3.1. Header Object 4.3.2. Times Object 4.3.3. Results Object Appendix A. LOSAPDR Processing Summary Appendix B. Example Label and Data Object B.1. Example Label B.2. Example Data File Tables A-1. Definition of Terms for Processing Figures 4-2. PDS Label Structure 4-3. Keyword-Value Pairs A-1. Spacecraft and Target Geometry A-2. Spline Fit ACRONYMS AND ABBREVIATIONS ASCII American Standard Code for Information Interchange CR Carriage Return FTP File Transfer Protocol hr hour Hz Hertz int integer JPL Jet Propulsion Laboratory km Kilometers LF Line Feed LOSAPDR Line of Sight Acceleration Profile Data Record LUNRES Gravity analysis program MGS Mars Global Surveyor min minutes mm millimeters PDS Planetary Data System RS Radio Science SCET Space Craft Event Time sec seconds SIS Software Interface Specification TBD To Be Determined z.f.r.j. zero-filled, right-justified 1. General Description 1.1. Overview This Software Interface Specification (SIS) describes the Gravity Science Line of Sight Acceleration Profile Data Record (LOSAPDR) produced for flight projects such as Lunar Prospector (LP) and Mars Global Surveyor (MGS) at the Jet Propulsion Laboratory (JPL) and delivered to the Planetary Data System (PDS). LOSAPDR files contain results from processing radio tracking data using program LUNRES. Splines are fitted to Doppler residual values resulting from spacecraft orbit solutions. The spline results are then interpreted as local accelerations, from which the size and location of mass anomalies within the target body can be inferred. A summary of the processing which leads to the LOSAPDR is given in Appendix A. Each LOSAPDR is accompanied by a full PDS label which completely describes its content and format. LOSAPDR files adhere to standards set by the PDS [1,2]. 1.2. Scope The format and content specifications in this SIS apply to all phases of the project for which the LOSAPDR is produced. 1.3. Applicable Documents [1] Planetary Data System Standards Reference, Jet Propulsion Laboratory Document D-7669, Part 2, Version 3.2, Pasadena, CA, 24 July 1995. [2] Planetary Science Data Dictionary Document, Pasadena: Jet Propulsion Laboratory Document D-7116, Rev. D, Pasadena, CA, 15 July 1996. 1.4. Subsystem Siting 1.4.1. Interface Location and Medium The LOSAPDR product is an electronic file on computer systems at the Jet Propulsion Laboratory. 1.4.2. Data Sources, Transfer Methods, and Destinations LOSAPDR files are created by program LUNRES running on a computer system at JPL. Input data include Orbit Data Files containing radio tracking data from the Deep Space Network. LOSAPDR files are delivered electronically to work stations of the parent flight project and/or to workstations of the Planetary Data System (PDS). Although the LOSAPDR is an ASCII file, machine to machine electronic transfers using the FTP utility should be carried out using FTP in binary mode. This will preserve the carriage-return line-feed record delimiters and ensure that file lengths are preserved. Note that some machines may need to modify the carriage-return line-feed structure after receiving the files and before using local utilities or application programs. 1.4.3. Generation Method and Frequency LOSAPDR files are created by program LUNRES. Each LOSAPDR contains data from one spacecraft orbit. LOSAPDRs are generated when the data for the appropriate orbits become available. 1.4.4. Pertinent Relationships with Other Interfaces None. 1.4.5. Labeling and Identification Names for LOSAPDR files have the form MPnnnnnV.LOS where "M" indicates the mission "L" for Lunar Prospector or "M" for Mars Global Surveyor; "P" denotes the mission phase "N" for Lunar Prospector nominal mission, "X" for Lunar Prospector extended mission, "O" for MGS orbit insertion, or "M" for MGS mapping; "nnnnn" is a five-digit zero-filled, right-justified (z.f.r.j.) orbit number; and "V" is the target body gravity field model identifier (e.g., "J" for many Lunar Prospector extended mission orbits). It is assumed that there will be only one LOSAPDR file for each gravity model, though improvements in the computational algorithm may result in a newer version of the file occasionally superseding an older one. Internal labeling of LOSAPDR files is accomplished with keywords and values as described in Section 4.2.1. 1.5. Assumptions and Constraints 1.5.1. Usage Constraints None. 1.5.2. Priority Phasing Constraints None. 1.5.3. Explicit and Derived Constraints None. 1.5.4. Documentation Conventions 1.5.4.1. Data Format Descriptions The LOSAPDR is a text file using ASCII character definitions. All double precision numbers (real) are represented using FORTRAN 1P1E23.16 format statements. Integers (int) are represented using FORTRAN I2 and I10 format statements. If a field is described as containing n bytes of ASCII character string data, this implies that the leftmost (lowest numbered) byte contains the first character, the next lowest byte contains the second character, and so forth. 1.5.4.2. Time Standards Within LOSAPDR files, times are expressed as a string of 23 ASCII characters YYYY-MM-DDThh:mm:ss.fff where "-", "T", ":", and "." are fixed delimiters; "YYYY" is the year "19nn" or "20nn"; "MM" is a two-digit month of year; "DD" is a two-digit day of month; "T" separates the date and time segments of the string; "hh" is hour of day; "mm" is the minutes of hour (00-59); "ss" is the seconds of minute (00-59); and "fff" is in milliseconds. The data type "TIME" is assigned to this format. When only the date is required the 10-character string YYYY-MM-DD may be substituted. The data type "DATE" is assigned to this format. Spacecraft times given in the form above are Spacecraft Event Times (SCET) in ephemeris time. Ground times, such as local processing time, indicate local time (Pacific Standard Time or Pacific Daylight Time, as appropriate). 1.5.4.3. Coordinate Systems Each LOSAPDR uses a single ad hoc inertial coordinate system, defined uniquely for that set of observations. At the reference time CALENDAR EPOCH (CEPOCH; see Appendix A and Appendix B.1) an inertial frame is defined by the instantaneous target-fixed frame [1,2]. All positions and velocities are then expressed with reference to that frame. Latitudes and longitudes, for example, are effectively specified with respect to the meridian and equator of the target-fixed frame at CEPOCH (see Appendix A). 1.5.4.4. Limits of This Document This document applies only to the LOSAPDR product. 1.5.4.5. Typographic Conventions This document has been formatted for simple electronic file transfer and display. Line lengths are limited to 80 ASCII characters, including line length delimiters. No special fonts or structures are included within the file. Constant width characters are assumed for display. 2. Interface Characteristics 2.1. Hardware Characteristics and Limitations 2.1.1. Special Equipment and Device Interfaces The LOSAPDR ASCII files are created on a JPL computer system and are delivered over networks to destination workstations and databases, as appropriate. Users of the LOSAPDR must have access to these destination facilities or to backup or archival media on which these files have been stored. 2.1.2. Special Setup Requirements None. 2.2. Volume and Size The LOSAPDR data for each spacecraft orbit consist of one file, as detailed in Section 4. File sizes vary, but a typical file contains 150 kilobytes. 2.3. Interface Medium Characteristics LOSAPDR files are electronic files. 2.4. Failure Protection, Detection, and Recovery Procedures None. 2.5. End-of-File Conventions End of file labeling complies with destination workstation or database standards. 2.6. End-of-Volume Conventions End of volume labeling complies with destination workstation or database standards. 3. Access 3.1. Programs Using the Interface Data contained in an LOSAPDR will be accessed by programs at the home institutions of science and other investigators. Those programs cannot be identified here. 3.2. Synchronization Considerations 3.2.1. Timing and Sequencing Considerations N/A 3.2.2. Effective Duration N/A 3.2.3. Priority Interrupts None. 3.3. Input/Output Protocols, Calling Sequences None. 4. Detailed Interface Specifications 4.1. Structure and Organization Overview The LOSAPDR is an ASCII file generated by the LUNRES Gravity Science software. It has a file name of the form described in Section 1.4.5. Each LOSADPR comprises three tables: a Header Table, a Times Table, and a Results Table. Each file is accompanied by a PDS label which fully describes both the content and format of the LOSAPDR [1]. The label is an ASCII file in its own right with the same name as the data file except for the extension "LBL". 4.2. PDS Label The PDS Label includes two components: a section of standard keyword=value entries, and a section of object definitions. The general structure is shown in Figure 4-2. An example label is shown in Appendix B.1. Although not shown here and in Appendix B.1, each line in the Standard Keyword and Value section and each line in the Object Definition sections is terminated by both the ASCII carriage return (hex 0D) and the ASCII line feed (hex 0A) characters. |====================================================================| | | | Figure 4-2. PDS Label Structure | | | |====================================================================| | PDS_VERSION_ID = PDS3 | | | RECORD_TYPE = FIXED_LENGTH | Standard | | FILE_RECORDS = nnn | Keywords | | RECORD_BYTES = nnn | and | | ... | Labels | | PRODUCT_RELEASE_DATE = YYYY-MM-DD | | | | | | OBJECT = LOSAPDR_HEADER_TABLE | Header | | ... | Object | | END_OBJECT = LOSAPDR_HEADER_TABLE | Definition | | | | | OBJECT = LOSAPDR_TIMES_TABLE | Times | | ... | Object | | END_OBJECT = LOSAPDR_TIMES_TABLE | Definition | | | | | OBJECT = LOSAPDR_RESULTS_TABLE | Results | | ... | Object | | END_OBJECT = LOSAPDR_TABLE | Definition | |=====================================================|==============| 4.2.1. Keyword-Value Pairs Keywords-value pairs are shown in Figure 4-3 and are defined in the text which follows [2]. Note that entries beginning with "^" are pointers to data objects (tables) in the LOSAPDR data file. Each line in Figure 4-3 ends with an ASCII carriage-return line-feed pair, which is not shown. |====================================================================| | | | Figure 4-3. Keyword-Value Pairs | | | |====================================================================| | PDS_VERSION_ID = PDS3 | | | RECORD_TYPE = FIXED_LENGTH | | | RECORD_BYTES = 202 | | | FILE_RECORDS = nnn | | | ^LOSAPDR_HEADER_TABLE = ("MPnnnnnV.LOS",nnn) | | | ^LOSAPDR_TIMES_TABLE = ("MPnnnnnV.LOS",nnn) | | | ^LOSAPDR_RESULTS_TABLE = ("MPnnnnnV.LOS",nnn) | | | INSTRUMENT_HOST_NAME = "ccccccc" | | | TARGET_NAME = "cccccccc" | Standard | | INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM" | Keywords | | DATA_SET_ID = "ccccccccccccccc" | and | | PRODUCT_ID = "MPnnnnnV.LOS" | Values | | DESCRIPTION = "ccccc" | | | SOFTWARE_NAME = "LUNRES;n.mm" | | | START_TIME = YYYY-MM-DDThh:mm:ss.fff | | | STOP_TIME = YYYY-MM-DDThh:mm:ss.fff | | | SPACECRAFT_CLOCK_START_COUNT = "N/A" | | | SPACECRAFT_CLOCK_STOP_COUNT = "N/A" | | | PRODUCER_ID = "cccccccccc" | | | PRODUCT_CREATION_TIME = YYYY-MM-DDThh:mm:ss.fff | | | PRODUCT_RELEASE_DATE = YYYY-MM-DD | | |=======================================================|============| PDS_VERSION_ID The version of the Planetary Data System for which these data have been prepared (by agreement between the flight project and PDS, set to PDS3). RECORD_TYPE The record format for the file (set to "FIXED_LENGTH"). RECORD_BYTES An integer number nnn giving the number of bytes per logical record throughout the file. The product of the number of records (FILE_RECORDS) and the number of bytes per record (RECORD_BYTES) is the size of the file in bytes. For the LOSAPDR, set to 202, which is the intrinsic length of records in the Results Object. FILE_RECORDS An integer number nnn giving the total number of records in the file. The multiplicative product of the number of records (FILE_RECORDS) and the number of bytes per record (RECORD_BYTES) is the size of the file in bytes. ^LOSAPDR_HEADER_TABLE Pointer to the start of the LOSAPDR Header Object. "MPnnnnnV.LOS" is the PRODUCT_ID, described below. The integer nnn gives the starting record number for the Header Object in the data file. Record numbering within the file starts from record 1, incrementing once for each subsequent record of length RECORD_BYTES. This pointer is set to "1". ^LOSAPDR_TIMES_TABLE Pointer to the start of the LOSAPDR Times Object. "MPnnnnnV.LOS" is the PRODUCT_ID, described below. The integer nnn gives the starting record number for the (spline interval) Times Object in the LOSAPDR data file. Record numbering within the file starts from record 1, incrementing once for each subsequent record of length RECORD_BYTES. This pointer is set to "7". ^LOSAPDR_RESULTS_TABLE Pointer to the start of the LOSAPDR Results Object. "MPnnnnnV.LOS" is the PRODUCT_ID, described below. The integer nnn gives the starting record number for the Results Object in the data file. Record numbering within the file starts from record 1, incrementing once for each subsequent record of length RECORD_BYTES. INSTRUMENT_HOST_NAME A character string which identifies the spacecraft. Acceptable values include "LUNAR PROSPECTOR" and "MARS GLOBAL SURVEYOR". TARGET_NAME A character string which identifies the target body. Acceptable values include "MOON" and "MARS". INSTRUMENT_NAME The character string "RADIO SCIENCE SUBSYSTEM". DATA_SET_ID The data set identification as defined by the Planetary Data System. Acceptable values include "LP-L-RSS-5-LOS-V1.0" for Lunar Prospector and "MGS-M-RSS-5-SDP-V1.0" for Mars Global Surveyor. PRODUCT_ID A character string of the form "MPnnnnnV.LOS" where the components are defined in Section 1.4.5. DESCRIPTION A character string "cccc" containing a brief description of the data product. SOFTWARE_NAME The character string "LUNRES;n.mm" where "LUNRES" is the generating program and "n.mm" denotes the version of that program used to create the data file. START_TIME A character string indicating the SCET of the first tracking data point, in the format YYYY- MM-DDThh:mm:ss.fff (see Section 1.5.4.2) STOP_TIME A character string indicating the SCET of the last tracking data point, in the format YYYY- MM-DDThh:mm:ss.fff (see Section 1.5.4.2) SPACECRAFT_CLOCK_START_COUNT The character string "N/A" SPACECRAFT_CLOCK_STOP_COUNT The character string "N/A" PRODUCER_ID A character string which identifies the group producing the file. For Lunar Prospector, the character string "LP GRAVSCI TEAM"; for Mars Global Surveyor, the character string "MGS GRAVSCI TEAM". PRODUCT_CREATION_TIME A character string indicating the date and time at which the file was created [in the format YYYY-MM- DDThh:mm:ss.fff (see Section 1.5.4.2)] PRODUCT_RELEASE_DATE A character string indicating the date at which the file was released to the Planetary Data System [in the format YYYY-MM-DD (see Section 1.5.4.2)] 4.2.2. Object Definitions Object Definitions are series of statement groups of the form OBJECT = OBJECT_NAME ATTRIBUTE_1 = ATTRIBUTE_1_VALUE ATTRIBUTE_2 = ATTRIBUTE_2_VALUE ... ATTRIBUTE_N = ATTRIBUTE_N_VALUE END_OBJECT = OBJECT_NAME where each indented line specifies an attribute of the object (its size, line length, etc.). Attributes can themselves be object definitions, allowing nesting within the definition statement. For example, a primary Object Definition may specify a table; nested Object Definitions can be used to specify each of the columns within the table. Data Objects within the LOSAPDR are the Header Object, the Times Object, and the Results Object. Each contains data in tabular form. Each Object Definition first defines the table itself; nested subsidiary Object Definitions are used to define each of the table columns. 4.3. Data File The data file includes three objects, each defined in part of the accompanying PDS label. 4.3.1. Header Object The Header Object is a single-row multi-column table containing information on initial values, control parameters, and simple calculations required by the generating program LUNRES. The Header Object is completely defined by the Header Object Definition in the PDS label. Column entries in the table are separated by ASCII commas (hex 2D). The total length of the header table must be an integral multiple of 202 bytes (the record length for the data blocks). A pad of 180 ASCII blank characters fills out the last record. An ASCII carriage return (hex 0D) and an ASCII line feed (hex 0A) follow the pad. The total length of the header table is thus 1212 characters -- exactly six times the value of RECORD_BYTES. 4.3.2. Times Object The Times Object is a table containing exact times bounding spline intervals. Each row in the table has RECORD_BYTES=202 bytes; the number of rows is given by NBKS (in the Header Object) and may be variable. Although not shown here, each line in the Times Object Definition is terminated by both the ASCII carriage return (hex 0D) and the ASCII line feed (hex 0A) characters. The table is a single column containing 23-character ASCII representations of double precision numbers. It is described completely by the Times Object Definition in the PDS label. Each row in the table is padded with 177 ASCII blanks followed by an ASCII carriage return (hex 0D) and an ASCII line feed (hex 0A) -- a total of RECORD_BYTES=202 characters. 4.3.3. Results Object The Results Object is a table containing results from spline fits to Doppler tracking residuals. It is completely described by the Results Object Definition below. Although not shown here, each line in the Results Object Definition is terminated by both the ASCII carriage return (hex 0D) and the ASCII line feed (hex 0A) characters. The table has eleven columns; its length is variable -- that is, it has a variable number of rows. Column entries are separated by ASCII commas (hex 2D). Appendix A - LOSAPDR Processing Summary Tracking data (Orbit Data Files) are used to obtain an orbit solution for the spacecraft expressed in Keplerian elements and derived quantities |============================================================================| | | | Table A-1 Definition of Terms for Processing | | | |============================================================================| | LISTED QUANTITY | PROGRAM | DESCRIPTION | | | MNEMONIC| | |-------------------------+---------+----------------------------------------| |ORBITAL SEMIMAJOR AXIS | SMA |Semi-major axis of spacecraft orbit (km)| |-------------------------+---------+----------------------------------------| |ORBITAL ECCENTRICITY | ECC |Eccentricity of spacecraft orbit | |-------------------------+---------+----------------------------------------| |ORBITAL INCLINATION | INC |Inclination of spacecraft orbit (deg) | |-------------------------+---------+----------------------------------------| |ASCENDING NODE LONGITUDE | NODE |Ascending node of spacecraft orbit (deg)| |-------------------------+---------+----------------------------------------| |PERIAPSIS ARGUMENT ANGLE | ARG |Argument of periapsis for spacecraft | | | | orbit (deg)| |-------------------------+---------+----------------------------------------| |TRUE ANOMALY ANGLE | F |True anomaly of spacecraft orbit (deg) | |-------------------------+---------+----------------------------------------| |MEAN ANOMALY ANGLE | M |Mean anomaly of spacecraft orbit (deg) | |-------------------------+---------+----------------------------------------| |ECCENTRIC ANOMALY ANGLE | E |Eccentric anomaly of spacecraft orbit | | | | (deg)| |-------------------------+---------+----------------------------------------| |ORBITAL PERIOD | P |Period of spacecraft orbit (hrs) | |-------------------------+---------+----------------------------------------| |PERIAPSIS LATITUDE | LATPER |Latitude of periapsis from target | | | | (deg N)| |-------------------------+---------+----------------------------------------| |PERIAPSIS LONGITUDE | LONPER |Longitude of periapsis from target (deg)| |-------------------------+---------+----------------------------------------| |PERIAPSIS RADIUS | RPER |Spacecraft distance from C/M at | | | | periapsis (km)| |-------------------------+---------+----------------------------------------| |PERIAPSIS VELOCITY | VPER |Spacecraft velocity at periapsis (km/s) | |-------------------------+---------+----------------------------------------| |PERIAPSIS ALTITUDE | APER |Altitude of S/C over reference surface | | | | at periapsis (km)| |-------------------------+---------+----------------------------------------| |APOAPSIS RADIUS | RAPO |Spacecraft distance from C/M at apoapsis| | | | (km)| |-------------------------+---------+----------------------------------------| |APOAPSIS VELOCITY | VAPO |Spacecraft velocity at apoapsis (km/s) | |-------------------------+---------+----------------------------------------| |APOAPSIS ALTITUDE | AAPO |Altitude of S/C over referenced surface | | | | at apoapsis (km)| |=========================|=========|========================================| TADD . . \ . . . . / . P, V, CEPOCH . . ooooooo target . . ooooooooooo / . . ooooooooooooo . . ooooooooooooo ^ . ooooooooooooo . . ooooooooooo . . ooooooo . . . . . . . / . TFIT . . Figure A-1. Schematic of spacecraft and target system, illustrating relationships among CEPOCH, TADD, and TFIT. Dots indicate orbit; spacecraft moves counterclockwise from CEPOCH through the fitted part of the orbit from CEPOCH+TADD to CEPOCH+TADD+TFIT. ---------- Doppler residuals DATA_RESID with respect to the solution are then calculated, and splines are fitted to the residuals. The fitted curves, after differentiation, can be interpreted as spacecraft accelerations relative to a simple Keplerian orbit about a homogeneous spherical target characterized by radius RADIUS and gravitational constant GM. The accelerations, in turn, may be used to infer anomalous mass concentrations within the otherwise homogeneous target. The initial state for the calculation is position P and velocity V at time CEPOCH. The position and velocity vectors are given in an inertial coordinate system which is identical to the target-fixed (rotating) frame at CEPOCH (and only at CEPOCH). CEPOCH is in spacecraft ephemeris time (E.T.). Time from the reference CEPOCH to the first tracking data point is TADD (minutes); time from the first data point to the last data point is TFIT (minutes). The spline is a cubic polynomial having continuous second derivatives at the end points, producing smooth accelerations when differentiated. The window, or interval, for which each polynomial applies has length DFIT (approximately 1-2 minutes). When DOBKS=-1, the windows have constant size throughout the entire profile. When DOBKS is positive the window size can vary -- as a function of spacecraft altitude, for example. The actual window or spline boundaries are tabulated in BKTIMX in units of minutes from midnight. | | D | O | X P | X P | L | X E | X spline R | / | X / R | \ E | X X-X X S | \ / \ X I | X-X X D | X X X U | X A | L | S | BKTIMX |<--DFIT-->| | \ | (1) (2) (3) (NBKS+1) +----+-------+------+-------+----------+---------/ /---+---+------ / / / CEPOCH CEPOCH+TADD CEPOCH+TADD+TFIT TIME Figure A-2. Spline fit and times used in defining it. Spline fit interval boundaries BKTIMX(n) are indicated above the horizontal axis; the number of intervals is NBKS. Interval length DFIT is specified only when it is a constant. ---------- The time TDSS (in UTC) at which a tracking data point is received at a ground station is: TDSS = TSC + TRANSA - DUTSEC where TSC = ephemeris time at the spacecraft (HH:MM:SS; see Results Table) TRANSA = one way light time in seconds DUTSEC = accumulated leap seconds (difference between ET and UTC) Appendix B - Example Label and Data Object B.1 Example Label The label which follows has been designed for the Lunar Prospector Line of Sight Acceleration Data Records. In the next section, an edited representative data object is shown PDS_VERSION_ID = "PDS3" RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 202 FILE_RECORDS = 1152 ^LOSAPDR_HEADER_TABLE = ("LX00002J.LOS",1) ^LOSAPDR_TIMES_TABLE = ("LX00002J.LOS",7) ^LOSAPDR_RESULTS_TABLE = ("LX00002J.LOS",113) INSTRUMENT_HOST_NAME = "LUNAR PROSPECTOR" TARGET_NAME = "MOON" INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM" DATA_SET_ID = "LP-L-RSS-5-LOS-V1.0" PRODUCT_ID = "LX00002J.LOS" DESCRIPTION = "The LOSAPDR (Line of Sight Acceleration Profile Data Record) is a set of three tables represented in ASCII character format which summarize the analysis of radio tracking data of orbiting planetary spacecraft (specifically, Lunar Prospector). The first table identifies input parameters and conditions; the second table gives times between which spline fits to data points are valid; and the third table gives times, Doppler residuals, spline fit residuals, and inferred values of spacecraft acceleration with respect to the nominal gravity field (LP100J) and orbit. The LOSAPDR is produced at the Jet Propulsion Laboratory under the supervision of A.S. Konopliv." SOFTWARE_NAME = "LOSRES.1999.4.6 " START_TIME = 1998-12-19T19:56:57.362 STOP_TIME = 1998-12-19T21:49:50.362 SPACECRAFT_CLOCK_START_COUNT = "N/A" SPACECRAFT_CLOCK_STOP_COUNT = "N/A" PRODUCER_ID = "LP GRAVSCI TEAM" PRODUCT_CREATION_TIME = 1999-04-06T16:11:25.000 PRODUCT_RELEASE_DATE = 1999-02-10 OBJECT = LOSAPDR_HEADER_TABLE ROWS = 1 COLUMNS = 42 ROW_BYTES = 1030 ROW_SUFFIX_BYTES = 182 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "The LOSAPDR header includes input data and summary results from initial ODP and LUNRES calculations. It is a single-row table with 42 columns, two of which have three elements each. The data are represented as ASCII characters; entries are delimited by commas. The total of the data plus delimiters is 1030 characters, followed by 180 padding characters and a carriage-return line-feed pair. The row thus has 1212 characters, which is exactly six times the value of RECORD_BYTES." OBJECT = COLUMN NAME = "PLANETARY RADIUS" DATA_TYPE = ASCII_REAL START_BYTE = 1 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "The assumed radius of the spherical planet (program mnemonic RADIUS)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "GM" DATA_TYPE = ASCII_REAL START_BYTE = 25 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETERS CUBED PER SECOND SQUARED" DESCRIPTION = "The assumed gravitational constant for the planet." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "CALENDAR EPOCH" DATA_TYPE = TIME START_BYTE = 49 BYTES = 23 UNIT = "N/A" DESCRIPTION = "The calendar epoch in ephemeris time of the initial state vector at the spacecraft. The initial state vector is given by SPACECRAFT POSITION and SPACECRAFT VELOCITY below. (program mnemonic CEPOCH)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "JULIAN EPHEMERIS DAYS" DATA_TYPE = ASCII_REAL START_BYTE = 73 BYTES = 23 FORMAT = "E23.16" UNIT = "DAY" DESCRIPTION = "The Julian date corresponding to CEPOCH (ephemeris time at the space- craft) (program mnemonic JED)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT POSITION" ITEMS = 3 ITEM_BYTES = 23 ITEM_OFFSET = 24 DATA_TYPE = ASCII_REAL START_BYTE = 97 BYTES = 71 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "The spacecraft position vector at CEPOCH, calculated in program ODP (program mnemonics XS, YS, and ZS)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT VELOCITY" ITEMS = 3 ITEM_BYTES = 23 ITEM_OFFSET = 24 DATA_TYPE = ASCII_REAL START_BYTE = 169 BYTES = 71 FORMAT = "E23.16" UNIT = "KILOMETER PER SECOND" DESCRIPTION = "The spacecraft velocity vector at CEPOCH, calculated in program ODP (program mnemonics DXS, DYS, and DZS)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT LONGITUDE" POSITIVE_LONGITUDE_DIRECTION = "EAST" DATA_TYPE = ASCII_REAL START_BYTE = 241 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Planetocentric longitude of the spacecraft corresponding to SPACECRAFT POSITION at CEPOCH (program mnemonic LONEP)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT HOUR ANGLE" DATA_TYPE = ASCII_REAL START_BYTE = 265 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "The hour angle of the spacecraft corresponding to SPACECRAFT POSITION at CEPOCH (program mnemonic HANG)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "DOBKS" DATA_TYPE = ASCII_INTEGER START_BYTE = 289 BYTES = 2 FORMAT = "I2" UNIT = "N/A" DESCRIPTION = "Flag for constant (-1) or variable (+1) time spacing in spline fits. If DOBKS=+1, the time intervals in BKTIMX will be unequal." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "RECORD SPACING" DATA_TYPE = ASCII_REAL START_BYTE = 292 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "Time spacing of the output records in the RESULTS_TABLE (program mnemonic DTACC). Large values may mean that spacing defaults to the spacing of the data points (no interpolated data)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "MINBKS" DATA_TYPE = ASCII_INTEGER START_BYTE = 316 BYTES = 10 FORMAT = "I10" UNIT = "N/A" DESCRIPTION = "Minimum number of data points in each spline interval (used only if DOBKS=+1)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "MAXBKS" DATA_TYPE = ASCII_INTEGER START_BYTE = 327 BYTES = 10 FORMAT = "I10" UNIT = "N/A" DESCRIPTION = "Maximum number of data points in each spline interval (used only if DOBKS=+1)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "BAND" DATA_TYPE = ASCII_REAL START_BYTE = 338 BYTES = 23 FORMAT = "E23.16" UNIT = "MILLIMETER PER SECOND" DESCRIPTION = "Conversion factor from Doppler to acceleration. Nominally 0.2955 for X-band data and 1.0833 for S-band data." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TADD" DATA_TYPE = ASCII_REAL START_BYTE = 362 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "Time from CEPOCH to first data point (at the spacecraft)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TFIT" DATA_TYPE = ASCII_REAL START_BYTE = 386 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "Time from TADD to last data point (at the spacecraft)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "DFIT" DATA_TYPE = ASCII_REAL START_BYTE = 410 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "Length of each spline interval (used only when DOBKS=-1)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "REJECT" DATA_TYPE = ASCII_REAL START_BYTE = 434 BYTES = 23 FORMAT = "E23.16" UNIT = "HERTZ" DESCRIPTION = "Threshold for rejection of bad data points." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "EARTH LONGITUDE" POSITIVE_LONGITUDE_DIRECTION = "EAST" DATA_TYPE = ASCII_REAL START_BYTE = 458 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Planetocentric longitude of Earth at CEPOCH (program mnemonic LNE)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "EARTH LATITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 482 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Planetocentric north latitude of Earth at CEPOCH (program mnemonic LTE)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TRANSA" DATA_TYPE = ASCII_REAL START_BYTE = 506 BYTES = 23 FORMAT = "E23.16" UNIT = "SECOND" DESCRIPTION = "One-way downlink light- time for a photon leaving the spacecraft at CEPOCH." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TRANSB" DATA_TYPE = ASCII_REAL START_BYTE = 530 BYTES = 23 FORMAT = "E23.16" UNIT = "SECOND PER SECOND" DESCRIPTION = "Rate of change of TRANSA" END_OBJECT = COLUMN OBJECT = COLUMN NAME = "DUTSEC" DATA_TYPE = ASCII_REAL START_BYTE = 554 BYTES = 23 FORMAT = "E23.16" UNIT = "SECOND" DESCRIPTION = "Difference between ephemeris time (ET) and universal time (UT)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "REFEP" DATA_TYPE = TIME START_BYTE = 578 BYTES = 23 UNIT = "N/A" DESCRIPTION = "Reference epoch for TRANSA and TRANSB at the spacecraft (same time system, and often the same value, as CEPOCH)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ORBITAL SEMIMAJOR AXIS" DATA_TYPE = ASCII_REAL START_BYTE = 602 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Semi-major axis of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic SMA)" END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ORBITAL ECCENTRICITY" DATA_TYPE = ASCII_REAL START_BYTE = 626 BYTES = 23 FORMAT = "E23.16" UNIT = "DIMENSIONLESS" DESCRIPTION = "Eccentricity of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic ECC)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ORBITAL INCLINATION" DATA_TYPE = ASCII_REAL START_BYTE = 650 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Inclination of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic INC)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ASCENDING NODE LONGITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 674 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Ascending node of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic NODE)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS ARGUMENT ANGLE" DATA_TYPE = ASCII_REAL START_BYTE = 698 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Argument of periapsis for spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic ARG)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TRUE ANOMALY ANGLE" DATA_TYPE = ASCII_REAL START_BYTE = 722 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "True anomaly of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic F)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "MEAN ANOMALY ANGLE" DATA_TYPE = ASCII_REAL START_BYTE = 746 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Mean anomaly of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic M)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ECCENTRIC ANOMALY ANGLE" DATA_TYPE = ASCII_REAL START_BYTE = 770 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Eccentric anomaly of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic E)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ORBITAL PERIOD" DATA_TYPE = ASCII_REAL START_BYTE = 794 BYTES = 23 FORMAT = "E23.16" UNIT = "HOUR" DESCRIPTION = "Period of spacecraft orbit. Obtained in the orbit solution of program ODP (program mnemonic P)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS LATITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 818 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Planetocentric north latitude at periapsis for spacecraft orbit (program mnemonic LATPER)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS LONGITUDE" POSITIVE_LONGITUDE_DIRECTION = "EAST" DATA_TYPE = ASCII_REAL START_BYTE = 842 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Planetocentric longitude of periapsis for spacecraft orbit (program mnemonic LONPER)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS RADIUS" DATA_TYPE = ASCII_REAL START_BYTE = 866 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Spacecraft distance from target center of mass at periapsis (program mnemonic RPER)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS VELOCITY" DATA_TYPE = ASCII_REAL START_BYTE = 890 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER PER SECOND" DESCRIPTION = "Spacecraft velocity at periapsis (program mnemonic VPER)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PERIAPSIS ALTITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 914 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Spacecraft altitude over reference surface at periapsis (program mnemonic APER)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "APOAPSIS RADIUS" DATA_TYPE = ASCII_REAL START_BYTE = 938 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Spacecraft distance from target center of mass at apoapsis (program mnemonic RAPO)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "APOAPSIS VELOCITY" DATA_TYPE = ASCII_REAL START_BYTE = 962 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER PER SECOND" DESCRIPTION = "Spacecraft velocity at apoapsis (program mnemonic VAPO)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "APOAPSIS ALTITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 986 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Spacecraft altitude over reference surface at apoapsis (program mnemonic AAPO)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "NBKS" DATA_TYPE = ASCII_INTEGER START_BYTE = 1010 BYTES = 10 FORMAT = "I10" UNIT = "N/A" DESCRIPTION = "Number of times in the Times Table defining spline intervals." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "NPOINT" DATA_TYPE = ASCII_INTEGER START_BYTE = 1021 BYTES = 10 FORMAT = "I10" UNIT = "N/A" DESCRIPTION = "Number of data points used to make this file." END_OBJECT = COLUMN END_OBJECT = LOSAPDR_HEADER_TABLE OBJECT = LOSAPDR_TIMES_TABLE ROWS = 106 COLUMNS = 1 ROW_BYTES = 23 ROW_SUFFIX_BYTES = 179 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "The LOSAPDR times table contains exact times bounding each spline interval. Each row contains one 23-digit number, 177 spaces, and a carriage-return line-feed pair." OBJECT = COLUMN NAME = "SPLINE BREAK TIMES" DATA_TYPE = ASCII_REAL START_BYTE = 1 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "The exact times of spline interval boundaries measured from midnight at the spacecraft (program mnemonic BKTIMX)." END_OBJECT = COLUMN END_OBJECT = LOSAPDR_TIMES_TABLE OBJECT = LOSAPDR_RESULTS_TABLE ROWS = 1040 COLUMNS = 11 ROW_BYTES = 202 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "The LOSAPDR Results Table contains the results from spline fits to Doppler tracking residuals. Each row in the table contains times, Doppler residuals, spacecraft position information, residuals to spline fits, and inferred spacecraft acceleration with respect to the nominal orbit. Each row has length 202 bytes; the first 200 are column data delimited by commas; the last two are a carriage- return line-feed pair." OBJECT = COLUMN NAME = "HH" DATA_TYPE = ASCII_INTEGER START_BYTE = 1 BYTES = 2 FORMAT = "I2.2" UNIT = "HOUR" DESCRIPTION = "The hour of a Doppler residual data point at the spacecraft." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "MM" DATA_TYPE = ASCII_INTEGER START_BYTE = 4 BYTES = 2 FORMAT = "I2.2" UNIT = "MINUTE" DESCRIPTION = "The minute of a Doppler residual data point at the spacecraft." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SS" DATA_TYPE = ASCII_INTEGER START_BYTE = 7 BYTES = 2 FORMAT = "I2.2" UNIT = "SECOND" DESCRIPTION = "The whole seconds of a Doppler residual data point at the spacecraft. Note that there are generally fractional seconds; for full time accuracy use OFFSET TIME." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "OFFSET TIME" DATA_TYPE = ASCII_REAL START_BYTE = 10 BYTES = 23 FORMAT = "E23.16" UNIT = "MINUTE" DESCRIPTION = "Offset from CEPOCH to the time of the Doppler residual data point or inter- polation (program mnemonic DMIN)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "DOPPLER RESIDUAL" DATA_TYPE = ASCII_REAL START_BYTE = 34 BYTES = 23 FORMAT = "E23.16" UNIT = "HERTZ" DESCRIPTION = "Doppler residual from input data (program mnemonic DATA_RESID)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT ALTITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 58 BYTES = 23 FORMAT = "E23.16" UNIT = "KILOMETER" DESCRIPTION = "Spacecraft altitude over reference surface (program mnemonic SC_ALT)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT LATITUDE" DATA_TYPE = ASCII_REAL START_BYTE = 82 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Spacecraft planetocentric north latitude (program mnemonic SC_LAT)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT LONGITUDE" POSITIVE_LONGITUDE_DIRECTION = "EAST" DATA_TYPE = ASCII_REAL START_BYTE = 106 BYTES = 23 FORMAT = "E23.16" UNIT = "DEGREE" DESCRIPTION = "Spacecraft planetocentric longitude (program mnemonic SC_LON)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "FIT RESIDUAL" DATA_TYPE = ASCII_REAL START_BYTE = 130 BYTES = 23 FORMAT = "E23.16" UNIT = "HERTZ" DESCRIPTION = "Doppler residual from fitted spline at HHMMSS (program mnemonic FIT_RESID)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "ACCELERATION" DATA_TYPE = ASCII_REAL START_BYTE = 154 BYTES = 23 FORMAT = "E23.16" UNIT = "MILLIMETER PER SECOND PER SECOND" DESCRIPTION = "Acceleration from fitted Doppler residual (program mnemonic ACCEL)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "HARMONIC ACCELERATION" DATA_TYPE = ASCII_REAL START_BYTE = 178 BYTES = 23 FORMAT = "E23.16" UNIT = "MILLIMETER PER SECOND PER SECOND" DESCRIPTION = "The acceleration in the line-of-sight direction due to the spherical harmonic gravity field (LP100J). This acceleration is to be added to the acceleration from the Doppler residual to obtain the total line-of-sight acceleration." END_OBJECT = COLUMN END_OBJECT = LOSAPDR_RESULTS_TABLE END B.2 Example Data File The listing below shows an example Header Table, Times Table, and Results Table from an example Data Object. Long lines wrap after each 70 characters; blanks padding lines have been omitted. .1738000000000000E+04, .4902800476015460E+04,1998-12-19T19:56:57.362, .2451167331219468E+07, .3741758852846081E+01, -.7318498199275959E+03, .1620164965425043E+04, .2977674198918101E-01, -.1507576585405230E+01, -.6962231168914452E+00, -.8970706405005299E+02, .1039548114945077E+03, 1, .1000000000000000E+21, 4, 1000, .1083300000000000E+01 , .0000000000000000E+00, .1128833333699033E+03, .8333333333333334E+00 .1538508877196222E+02, -.4190051958576807E+01, -.4787442125265000E+01, .1321500914263461E+01, .0000000000000000E+00, .5618357258662581E+02, 1998-12-19T19:56:57.362, .1778181746793010E+04, .8322610191421140E-02, .8920288160027347E+02, -.1641476817768940E+03, .2035837284048299E+03, -.8897665715273091E+02, -.8802322568293904E+02, -.8849991269768408E+02, .1869043802729941E+01, -.2328399111109770E+02, -.8887831375123606E+02, .1763382633264952E+04, .1674359008116209E+01, .2538263326495166E+02, .1792980860321069E+04, .1646718970683348E+01, .5498086032106880E+02, 106, 1040 .1196956034527843E+04 .1197789367861177E+04 .1198622701194510E+04 .1199456034527843E+04 ... .1309456034527843E+04 .1310289367861177E+04 19,56,57, .0000000000000000E+00, -.1502572267922315E+00, .397943286213 1125E+02, .6569039926461633E+02, -.8970706405005299E+02, -.130077035951 3750E+00, .9956235464222281E-01, -.1338888862673443E+00 19,57,02, .8333333339542151E-01, -.8306550361760215E-01, .397252560348 7293E+02, .6542278856077859E+02, -.8969927626810956E+02, -.122067789525 3115E+00, .1082277614529738E+00, -.1279473508098096E+00 19,57,07, .1666666667287548E+00, -.1237559812890394E+00, .396562171326 6478E+02, .6515515651416189E+02, -.8969166040049306E+02, -.113494390629 8949E+00, .1142298676792334E+00, -.1210989161461684E+00 ...