Data Set Information
|
| DATA_SET_NAME |
2001 MARS ODYSSEY RADIO SCIENCE RAW DATA SET - V1.0
|
| DATA_SET_ID |
ODY-M-RSS-1-RAW-V1.0
|
| NSSDC_DATA_SET_ID |
|
| DATA_SET_TERSE_DESCRIPTION |
|
| DATA_SET_DESCRIPTION |
Data Set Overview : The 2001 Mars Odyssey (ODY) Radio Science (RS) Raw Data Archive (RDA) is a time-ordered collection of raw and partially processed data collected during the 2001 Mars Odyssey mission to Mars. There were no formally recognized radio science investigations within the mission. For information on investigations conducted using Mars Global Surveyor (with similar capabilities) see [TYLERETAL2001]. This data set was collected beginning in 2002, as the spacecraft was nearing its circular orbit, and during its Mapping phase which followed. Two types of measurements were conducted; these are known as closed-loop and open-loop recordings. The closed-loop system used a phase-lock loop in the ground receiver to track the downlink signal, reporting both amplitude and frequency at rates typically of 1-10 times per second. In the open-loop system, the signal was simply converted to a baseband frequency range; the entire passband was sampled and recorded for later processing. Closed-loop data are efficient for characterizing slowly changing signals and are the input to operational navigation and orbit-determination processes. Open-loop data (because of their much higher rate and volume) are collected only when the signal is expected to be very dynamic -- such as during a spacecraft maneuver or an occultation. Open-loop data were limited to data from the high-gain antenna (HGA) deployment and solar conjunction because there was no science open-loop requirement within the mission. Solar conjunction data were collected by the JPL Radio Science Systems Group on a 'best efforts' basis during August 2002. The data set includes three primary data types. Archival Tracking Data Files (ATDFs or TDFs) are the most primitive (and most voluminous) product of the closed-loop system. Orbit Data Files (ODFs) are edited versions of ATDFs, specifically targeted to spacecraft navigators and scientists interested in gravity fields. Radio Science Receiver records (RSRs) are the primary data type from the open-loop system. Typical users of these data might analyze range and Doppler measurements in ATDFs or ODFs to reconstruct the spacecraft trajectory. Relevant questions would include the measurement uncertainties in range and Doppler at different DSN antennas; these could set constraints on any model of Mars' gravity field developed later, for example. Analysis of RSRs could help determine pointing of the spacecraft high-gain antenna (HGA) during and after its deployment. Parameters : The ATDF is the primary output from the ODY closed-loop system. ATDFs have 150 fields, though not all had been assigned during the ODY era. Each ATDF in the data set is accompanied by a full PDS label which defines both the content and the format of the file at the bit level. ATDF data fields include: Range High- or low-rate Doppler High or low-rate downlink phase Differential Range vs Integrated Doppler (DRVID) Allan deviation Smoothed noise Uplink phase Other information included in ATDF data records is date and time; spacecraft ID; ground station and its configuration; status flags and values reported by various ground systems; calibration values, noise estimates, and tolerances (station delay, transmitter power, etc.); and signal strength. The ODF is an edited version of the ATDF; it is a smaller file, issued more frequently than the ATDF. It contains the most important information (range and Doppler) needed by spacecraft navigators and investigators interested in determining gravitational fields of bodies such as Mars. Each ODF is accompanied by a full PDS label which describes both the content and format of the associated file. ODF data fields include: Narrowband spacecraft VLBI, Doppler mode (cycles) Narrowband spacecraft VLBI, phase mode (cycles) Narrowband quasar VLBI, Doppler mode (cycles) Narrowband quasar VLBI, phase mode (cycles) Wideband spacecraft VLBI (nanoseconds) Wideband quasar VLBI (nanoseconds) One-way Doppler (Hertz) Two-way Doppler (Hertz) Three-way Doppler (Hertz) One-way total count phase (cycles) Two-way total count phase (cycles) Three-way total count phase (cycles) PRA planetary operational discrete spectrum range (range units) SRA planetary operational discrete spectrum range (range units) RE(GSTDN) range (nanoseconds) Azimuth angle (degrees) Elevation angle (degrees) Hour angle (degrees) Declination angle (degrees) Radio Science Receiver records (RSRs) contain samples of open loop receiver output. Each block of data samples is accompanied by a 260-byte header which captures important acquisition parameters. Each RSR is accompanied by a full PDS label which describes both the content and format of the file at the bit level. Header information includes: Date and time of the first data sample Sample rate and channel assignment Phase/frequency of the numerically controlled oscillator Gain of the channel Processing : ATDFs are screened for 'bad' data points, which are removed before the file is released by the JPL Radio Metric Data Conditioning Team (RMDCT). ODFs are abstracted from subsets of ATDF data. The open-loop data delivered to Stanford were in the RSR (Radio Science Receiver) format. A full PDS label accompanies each TDF, ODF, and RSR file and gives a bit level description of the content and format. Data : Data are stored on CD-WO volumes approximately chronologically. Files of some types were delayed in delivery to Stanford and may be out of strict chronological order on the CDs. Users should consult listings in the INDEX/CUMINDEX.TAB file to ascertain full coverage of each data type. TDFs were created approximately every 1-2 days during the ODY mission. They are stored in the TDF directory on CD volumes. File names are of the form ydddeeeC.TDF where y is the one-digit year of the first data, ddd is the three-digit day-of-year of the first data, eee is the three-digit day- of-year of the last data, and C is a single letter (beginning with 'A') denoting the sequence in which files with the same ydddeee were handled. Generally ydddeeeB.TDF is a revised version of ydddeeeA.TDF. The PDS label has file name ydddeeeC.LBL. The typical TDF contains about 40 Mbytes. ODFs were typically issued daily during the ODY mission; during periods of high spacecraft activity (such as around maneuvers) ODFs were released more often. ODFs are stored in the ODF directory. File names are of the form ydddeeeC.ODF where the file name components are the same as for the TDF (previous paragraph). In most cases ydddeeeB.ODF was NOT simply a revised version of ydddeeeA.ODF; there were many requests for special ODF processing -- to obtain higher time resolution over short intervals, for example. The PDS label has file name ydddeeeC.LBL. Typical ODF file sizes are small multiples of 8064 bytes (e.g., less than 100 kB). Radio Science Receiver records (RSRs) were produced whenever the RSR was set to 'record' mode. These files are stored in the RSR directory. In most cases, the entire RSR run was collected into a single ODR file. But in other cases, it was more convenient to subdivide the RSR data; queries were issued for shorter time spans, and separate files were produced. File names are of the form ydddhhmm.RSR where y is the one-digit year of the first data, ddd is the day-of-year of the first data, hh is the hour on which the first sample was taken, and mm was the minute on which the first sample was taken. In cases where two files had the same ydddhhmm (for example, two DSN stations began recording at the same time, or a second query was submitted for data which appeared suspicious after the first query was processed), the less significant digit in mm of the second file was converted to a letter ('0' became 'A', '1' became 'B', ..., '9' became 'J'). In cases were three files had the same ydddhhmm, the less significant mm digit was converted to 'K', 'M', etc. The PDS label has file name ydddhhmm.LBL. At 2000 complex samples per second (16 bits I, 16 bits Q), a 7-minute RSR session would yield an 8260 byte record each second or about 3.5 MB total. Ancillary Data : An extensive set of ancillary files is needed for proper analysis and interpretation of the radio data (file types TDF, ODF, and ODR). These are organized in parallel directories and stored approximately chronologically. When a file type is not represented on a CD-WO volume, the corresponding directory has been omitted. With the exception of files stored in the CALIB directory, ancillary files appear on only one CD-WO volume. Users should refer to the INDEX/CUMINDEX.TAB listing to locate ancillary files. Files in the CALIB Directory ---------------------------- Files in the CALIB directory are those likely to have wide applicability in working with the raw data. They help unpack and allow use of the raw data, rather than being 'instrument' calibration data per se. They include clock conversion files, files of planetary constants, HGA mounting data files, and leapsecond files. Each file is accompanied by a PDS minimal label. Clock Conversion files were produced by the JPL/PDS Navigation Ancillary Information Facility (NAIF) for use with NAIF-developed and ODY-provided software. These are ASCII files of variable length records. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed pair (ASCII 10), which may need to be converted to either or before the file is used on the local machine. File names have the form TSCnnnnn.SCK where nnnnn is a sequence number beginning with 00001 and the file with the highest number is the most recent. The value of nnnnn is set by NAIF. Planetary Constants files were produced by the JPL/PDS Navigation Ancillary Information Facility (NAIF) for use with NAIF-developed and ODY-provided software. These are ASCII files of variable length records. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed pair (ASCII 10), which may need to be converted to either or before the file is used on the local machine. File names have the form PCKydddC.TPC where y is the one-digit year of the file creation date, ddd is the day-of-year of the file creation date, and C is a character denoting sequence when more than one file with the same yddd is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Leapsecond files were produced by the JPL/PDS Navigation Ancillary Information Facility (NAIF) for use with NAIF-developed and ODY-provided software. These are ASCII files of variable length records. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed pair (ASCII 10), which may need to be converted to either or before the file is used on the local machine. File names have the form LSKydddC.TLS where y is the one-digit year of the file creation date, ddd is the day-of-year of the file creation date, and C is a character denoting sequence when more than one file with the same yddd is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Antenna Reconstruction Files are typically used in conjunction with Antenna Gimbal Kernel (AGK) files to determine the pointing of an antenna or the position of its phase center with respect to the spacecraft center of mass. There are three types of Antenna Reconstruction Files: the Antenna SPK (ASP) File, the Hinge CK (HCK) File, and the Text Frame Kernel (TFK) File. An ASP file contains the locations of low-gain antennas and boom lengths for the high-gain antenna (HGA). The HCK file contains hinge angles for the (deployed) HGA. The TFK file contains information on coordinate frame definitions for translating between the spacecraft frame and the frame of the high-gain antenna. File names are of the forms HGAnnnnn.ASP, HINGEnnn.HCK, and HGAnnnnn.TFK, where the 'n' string gives a sequence number. ASP and HCK files are ASCII files in NAIF transfer format; TFK files are ASCII files. In all cases, each record is delimited by the ASCII carriage-return (ASCII 13) line-feed (ASCII 10) pair. On some systems it may be necessary to convert the pair to either or before using the file on the local machine. Each Antenna Reconstruction File is accompanied by a PDS minimal label with the same file name except for an extension of .LBL. Antenna Gimbal Kernel Files (AGK Directory) ------------------------------------------- Antenna Gimbal Kernel files were produced by NAIF. Each AGK file contains information on the state of the HGA azimuth and elevation gimbals as a function of time. These are ASCII files in NAIF transfer format. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed (LF> (ASCII 10) pair, which may need to be converted to either or before the file is used on the local machine. File names have the form ydddeeeZ.AGK where 'y' is the least significant digit of the year in which data in the file begin, 'ddd' is the day-of-year when data begin, 'eee' is the day-of-year when data end, and 'Z' is a single upper case letter indicating order of files when there is more than one with the same 'ydddeee' in the data set. Z is 'A' for the first file, 'B' for the second, etc. Each AGK file is accompanied by a PDS minimal label with file name ydddeeeZ.LBL. Typical file sizes are 1 MByte. Angular Momentum Desaturation Files (AMD Directory) --------------------------------------------------- Angular Momentum Desaturation files were produced by the ODY Spacecraft Team (SCT). Each AMD file documents a set of AMD events on the spacecraft. These are ASCII files of variable length records. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed pair (ASCII 10), which may need to be converted to either or before the file is used on the local machine. File names have the form ydddeeeC.AMD where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each AMD file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 1500 bytes. Browse Files (BRO Directory) ---------------------------- Browse files are composite PostScript files summarizing quick-look processing of RSR data. Each file has a name of the form ydddhhmm.PSn where ydddhhmm is identical to the character string in the source RSR file and n is the receiver channel represented in the data. Each BRO file is accompanied by a detached PDS label with name ydddhhmm.LBL. Only one channel n is expected from each RSR. Each PostScript file is sized to fit on a single 8-1/2x11 inch page. Each landscape format page includes four panels showing a histogram of raw data (12-bit) samples (upper left), one-minute average power spectra derived from the raw samples (upper right), one-second averages of raw sample power versus time (lower left), and an extract of the first few lines of the source RSR PDS label (lower right). BRO files may be helpful in quickly scanning data to determine which files are suitable for closer study. Earth Orientation Parameter Files (EOP Directory) --------------------------------------------------- Earth Orientation Parameter files were produced by the Time and Earth Motion Precision Observation (TEMPO) Group at JPL. They documented and predicted Earth rotation (rate and axis). These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddzeee.EOP where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, z is the one-digit year of the last data, and eee is the day-of-year of the last data in the file. EOP files were typically released on Tuesdays and Fridays. There are both 'long' and 'short' versions. The long file covered past motion since about 1962 and a prediction for about three months into the future; these files have typical sizes of 860 kB. The short file covered the most recent 9-12 months of past motion and a prediction for 1-3 months into the future; these files are typically 30 kB. Each EOP file is accompanied by a PDS minimal label with file name ydddzeee.LBL. Ionosphere Calibration Files (ION Directory) --------------------------------------------------- Ionosphere Calibration files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They documented and predicted Earth ionospheric conditions. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeC.ION where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. ION files were usually released at one week intervals to cover a single month; ydddeeeA.ION would be the file released during the first week, ydddeeeB.ION would be the file released during the second week, etc. Each ION file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 50 kB. In mid-2003 the method of producing Ionosphere Calibration files was improved. Global Ionosphere Map (GIM) software created daily Global Ionospheric Maps from global GPS data. Each day, a final map was created for the UT day three days previously and a preliminary map was created for the UT day immediately before. Also created were predict maps a couple times a week by averaging recent 'normal' days. Then the software evaluated the maps at the spacecraft line-of-sight and fitted the results to a normalized polynomial versus time over each spacecraft pass. This was done for all three modes: final, preliminary, and predict. Then the software selected the best available calibration for each pass (in priority order final > preliminary > predict). Then the operator ran a plotting program to view all of the calibrations and overrode the default selections where desired. The mapping technique is described by [MANNUCCIETAL1998]. Light Time Files (LIT Directory) --------------------------------------------------- Light Time files were produced by the ODY Navigation Team (NAV). They gave radio propagation time from the spacecraft to Earth vs time. These are ASCII files of fixed length records. Each record is delimited by an ASCII carriage-return (ASCII 13) line-feed pair (ASCII 10), which may need to be converted to either or before the file is used on the local machine. File names have the form ydddeeeC.LIT where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each LIT file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 1 MB. Maneuver Implementation/Reconstruction Files (MIF Directory) --------------------------------------------------- Maneuver Implementation/Reconstruction files were produced by the ODY Spacecraft Team (SCT); they documented spacecraft maneuver events. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeC.MIF where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each MIF file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are 2327 bytes. Maneuver Performance Data Files (MPD Directory) --------------------------------------------------- Maneuver Performance Data files were produced by the ODY Spacecraft Team (SCT). They contain estimates of spacecraft mass and center of mass; moments of inertia; thruster locations, directions, and magnitudes; and propellant flow rate. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeC.MPD where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each MPD file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are 4 kB. Maneuver Profile Files (MPF Directory) --------------------------------------------------- Maneuver Profile Files were produced by the ODY Navigation Team (NAV). They are generic descriptions of orbit adjustments used by ODY during aerobraking. These are ASCII files of variable length records. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair. File names have the form XnnnDDCC.MPF where X is a character, nnn is a 3-digit number, DD indicates the adjustment direction ('UP' or 'DN'), and CC indicates the sequence if there is more than one file with the same XnnnDD. CC starts from 'AA'. Each MPF is accompanied by a PDS minimal label with file name XnnnDDCC.LBL. Typical file sizes are less than 700 bytes. Orbit Propagation and Time Generation Files (OPT Directory) --------------------------------------------------- Orbit Propagation and Time Generation files were produced by the ODY Navigation Team (NAV). They contain estimates of event timing (e.g., equator crossings) that depend on precise knowledge of the spacecraft orbit. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeC.OPT where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each OPT file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 100 kB. Solar Array Kernel Files (SAK Directory) --------------------------------------------------- Solar Array Kernel files were produced by the ODY Spacecraft Team (SCT). They give the attitude of the solar array panel as a function of time. These are ASCII files of variable length records in a special NAIF 'transfer' format. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair, which may need to be removed before the file is used on the local machine. After delimiter conversion (if needed) the file would ordinarily be passed through the NAIF utility SPACIT or TOBIN to convert it to the local binary format. File names have the form ydddeeeC.TCK where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each TCK file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 5 MB. Small Forces File (SFF Directory) --------------------------------------------------- Small Forces Files were created from the ODY spacecraft engineering telemetry stream. These are ASCII files of variable length records. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair. File names have the form ydddeeeC.SFF where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each SFF file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 0.1 MB. File content and structure is defined by SFF_SIS.TXT in the DOCUMENT directory. Well into the mission (July 2005) SFF files from the aerobraking period were obtained and added to the archive. As a result, files covering 2002-01-16 and earlier are PDS TABLE objects with full PDS labels, while the files collected for later dates have the properties described in the paragraph above. The file content, delimiters, and file naming convention are the same for the aerobraking data; SFF_SIS.TXT remains relevant. Only the format is different. Sequence of Events Files (SOE Directory) --------------------------------------------------- Sequence of Events Files were produced by the ODY Mission Control Team. These are ASCII files of variable length records. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair, which may need to be removed before the file is used on the local machine. File names have the form ydddeeeC.SOE where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each SOE file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 1 MB. Spacecraft/Planetary Ephemeris (SPK) Files (SPK Directory) --------------------------------------------------- Spacecraft/Planetary Ephemeris Files (also known as SP kernels or SPK files) were produced by the ODY Navigation Team (NAV). These files give spacecraft and planetary ephemerides. These are ASCII files of variable length records in a special NAIF 'transfer' format. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair, which may need to be removed before the file is used on the local machine. After delimiter conversion (if needed) the file would ordinarily be passed through the NAIF utility SPACIT or TOBIN to convert it to the local binary format. File names have the form ydddeeeC.SPK where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each SPK file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 5 MB. Spacecraft Attitude (CK) Files (TCK Directory) --------------------------------------------------- Spacecraft Attitude Files (also known as C kernels or CK files) were produced by the ODY Spacecraft Team (SCT). These are ASCII files of variable length records in a special NAIF 'transfer' format. Each record is delimited by a carriage-return (ASCII 13) line-feed (ASCII 10) pair, which may need to be removed before the file is used on the local machine. After delimiter conversion (if needed) the file would ordinarily be passed through the NAIF utility SPACIT or TOBIN to convert it to the local binary format. File names have the form ydddeeeC.TCK where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. Each TCK file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are less than 5 MB. Troposphere Calibration Files (TRO Directory) --------------------------------------------------- Troposphere Calibration files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They documented and predicted Earth tropospheric conditions. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeC.TRO where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and C is a character denoting sequence when more than one file with the same ydddeee is handled. C starts from 'A' and progresses to 'B', 'C', etc. with increasing numbers of similar coverage files. TRO files were typically released at the beginning of a month and covered the previous month. Each TRO file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. Typical file sizes are 100 kB. Starting in early 2001, TSAC began basing TRO files on measurements using the Global Positioning Satellite (GPS) system. These files can be distinguished by an ORIGINAL_PRODUCT_ID beginning with 'ATC' rather than the earlier 'TROPCAL'. Detailed file structure was slightly different, but the same Software Interface Specification (SIS) was used. DSN Weather Files (WEA Directory) --------------------------------------------------- DSN Weather files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. Files give weather calibration information for DSN complexes. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). File names have the form ydddeeeD.WEA where y is the one-digit year of the first data in the file, ddd is the day-of-year of the first data in the file, eee is the day-of-year of the last data in the file, and D is a single digit denoting the DSN complex at which the data were acquired ('1' for Goldstone, '4' for Canberra, or '6' for Madrid). WEA files were typically released weekly and contain all weather data for the complex since 1 January. Each WEA file is accompanied by a PDS minimal label with file name ydddeeeC.LBL. The files grow at the rate of approximately 90 kB per month. Coordinate System : SPK, TCK, and SAK files can be converted to a wide range of coordinate frames by the NAIF reader routines. Other data types are not dependent on definition of a coordinate system. Software : Software for parsing, reducing, and analyzing data such as these has been developed at Stanford University and elsewhere. Because such software must usually operate at the bit-level and is written for a narrow range of platforms, it is not suitable for general distribution. No software is included with this archival data set. Media/Format : The archival data set is written on CD-WO media using the Yamaha/GEAR authoring system. The CD-WO volumes conform to ISO 9660 standards.
|
| DATA_SET_RELEASE_DATE |
2002-02-28T00:00:00.000Z
|
| START_TIME |
2002-01-01T12:00:00.000Z
|
| STOP_TIME |
2004-12-31T12:00:00.000Z
|
| MISSION_NAME |
2001 MARS ODYSSEY
|
| MISSION_START_DATE |
2001-01-04T12:00:00.000Z
|
| MISSION_STOP_DATE |
N/A (ongoing)
|
| TARGET_NAME |
MARS
SUN
|
| TARGET_TYPE |
PLANET
SUN
|
| INSTRUMENT_HOST_ID |
ODY
|
| INSTRUMENT_NAME |
RADIO SCIENCE SUBSYSTEM
|
| INSTRUMENT_ID |
RSS
|
| INSTRUMENT_TYPE |
RADIO SCIENCE
|
| NODE_NAME |
Geosciences
|
| ARCHIVE_STATUS |
ARCHIVED_ACCUMULATING
|
| CONFIDENCE_LEVEL_NOTE |
Overview : Data in this archival data set have been collected to support radio science investigations, including derivation of the gravity field of Mars. These are similar to data collected using other spacecraft and are believed to be generally of good quality. Review : Because there was no formal radio science component to the 2001 Mars Odyssey mission, the review of these data will be conducted by the early users of the data set who have acquired files from the Planetary Data System. Their comments, criticisms, and suggestions will be evaluated to determine whether corrections are needed in future volumes or whether early volumes should be modified and reissued. Data Coverage and Quality : Data are essentially continuous beginning in early 2002. The coverage on each archival volume was keyed to the dates of the included ODF's. During low-volume periods approximately a month of data was included on each volume (e.g., ODRS_0008 contains data primarily from June 2002). Solar superior conjunction occurred on 2002-08-12 and again on about 2004-09-15. RSR data were collected on a 'best efforts' basis during August 2002 for future studies of the solar corona. The spacecraft radio system was in two-way mode and the signal was sampled at 1000 samples/s for the 90 minutes of each orbit when the spacecraft was not occulted. There was usually one 70-m DSN pass per day. Mars opposition occurred during late summer 2003 and fall 2005. Well into the mission (July 2005) radio tracking and small forces data (types ODF, TDF, and SFF) were obtained for the aerobraking phase of the mission (late 2001 and early 2002). These data were folded into the regular archiving stream and appear on volumes in the range ODRS_0094 to ODRS_0100. Limitations : The limitations in this data set follow from the quality of the execution, which is described above under Data Coverage and Quality.
|
| CITATION_DESCRIPTION |
2004-02-24 RS:simpson Add ARCHIVE_STATUS and ;Simpson, R.A., 2001 Mars Odyssey Radio Science Raw Data Set - Map V1.0, ODY-M-RSS-1-RAW-V1.0, NASA Planetary Data System, 2004.
|
| ABSTRACT_TEXT |
2004-02-27 RS:simpson added2004-03-01 RS:simpson revisedThis data set contains archival raw, partially processed, and ancillary/supporting radio science data acquired during the 2001 Mars Odyssey (ODY) mission. The radio observations were carried out using the ODY spacecraft and Earth-based receiving stations of the NASA Deep Space Network (DSN). The observations were designed to test the spacecraft radio system, the DSN ground system, and ODY operations procedures and to be used in reconstructing the spacecraft orbit, generating high-resolution gravity field models of Mars, and determining the nature of the near-Sun solar plasma. Of most interest are likely to be the Orbit Data Files in the ODF directory and the ionospheric and tropospheric media calibration files in the ION and TRO directories, respectively. The first ODF in the data set begins on 2002-01-06, which was actually in the late stages of the Aerobraking Phase and just before periapsis was lowered for about 2 weeks to about 200 km; the Mapping altitude was about 400 km. Data were delivered to PDS in approximately chronological order at the rate of 1-3 CD-WO volumes per month, of which about 0.01 GB/month were ODF's. By volume, the largest data type was either the Archival Tracking Data File (TDF; until early 2003) or the Tracking and Navigation File (TNF; beginning early 2003), both of which served as parents of the ODF.
|
| PRODUCER_FULL_NAME |
RICHARD A. SIMPSON
|
| SEARCH/ACCESS DATA |
Geosciences Web Services
Basic Browser
Geosciences Online Archives
|
|
.png)
.png)
