PDS_VERSION_ID = PDS3
RECORD_TYPE = STREAM
OBJECT = TEXT
INTERCHANGE_FORMAT = ASCII
PUBLICATION_DATE = 2009-02-06
NOTE = "N/A"
END_OBJECT = TEXT
END
Mars Global Surveyor Radio Science Team
Electron Density Profile Archive
(MGS-M-RSS-5-EDS-V1.0)
AAREADME.TXT
R.A. Simpson
Stanford University
==============================================================================
OVERVIEW
==============================================================================
This archival volume contains the entire collection of radio occultation
ionospheric electron density (EDS) profiles derived from Mars Global Surveyor
(MGS) data during the MGS mission. The profiles were archived previously as
part of the MGS-M-RSS-5-SDP-V1.0 data set, which is contained in a different
archive volume. These are the same profiles, but they have been collected
into a single volume where they are organized chronologically. The
accompanying PDS detached labels are also the same except for minor edits
needed for conformance to the new data set.
==============================================================================
VOLUME STRUCTURE
==============================================================================
The volume has four files and four directories at the root level.
The AAREADME.TXT file (this file) provides an overview of the archive;
the ERRATA.TXT file contains notes, warnings, and known errors in the data set
at the time the volume was produced; and the VOLDESC.CAT file contains catalog
information.
The DATA directory contains two sub-directories:
EDS directory contains electron density files arranged into
subdirectories by year and month.
The OCS directory contains a single file which is a summary table of all
5600 electron density profiles (the slightly edited header record from each
EDS file). Each entry in the table gives the latitude and longitude of the
occultation point, the solar longitude (Ls) of Mars, the solar zenith angle,
the local true solar time, names of files used in the processing, and the
name of the parent EDS file.
In the INDEX directory the INDEX.TAB file contains a listing of the data
files in the volume, together with some properties of those files.
The CATALOG directory contains descriptive information. Included are
files describing the mission, instrument, and data set.
The DOCUMENT directory contains more specific information on the file
organization and structure. Included is a Software Interface Specification
(SIS) document, describing the organization of the volume and and its files.
Also included is the OCCLOG.TAB file, which is a summary of each observation
opportunity with equipment settings from data acquisition and results from
early processing. This table has 33888 rows, including summaries of tests
and failed observation attempts.
The diagram below shows the organization of this volume, starting from
the root of the compact disc.
root
|
|- AAREADME.TXT
|- ERRATA.TXT
|- VOLDESC.CAT
|- CHECKSUMS.TXT
|
|- CATALOG
| |
| |- CATINFO.TXT Streamlined PDS catalog files
| |- MGS_MISSION.CAT for mission, host, instrument,
| |- MGS_INST_HOST.CAT references, personnel, data
| |- MGS_RSS_INST.CAT set, and target.
| |- MGS_RSS_REF.CAT
| |- MGS_RSS_PERSON.CAT
| |- MGS_RSS_5_EDS_DS.CAT
| |- MGS_TARGET.CAT
|
|- DOCUMENT
| |
| |- DOCINFO.TXT Overview of directory
| |- OCCLOG.TAB Summary of observation attempts
| |- OCCLOG.LBL PDS label for OCCLOG.TAB
| `- EDS_VOLM.TXT SIS for the volume
|
|- INDEX
| |
| |- INDXINFO.TXT Overview of directory
| |- INDEX.LBL Label to INDEX.TAB
| `- INDEX.TAB Table of contents for this volume
|
|
| DATA DIRECTORIES
|
|- OCS Occultation Summary File
| |
| |- 812506AA.OCS Summary of EDS files
| `- 812506AA.LBL PDS label for above
|
`- EDS Electron Density Profiles
|
| Directory containing EDS files organized into
... subdirectories by year and month. Typical
file names are:
ydddHmmN.EDS Nth solution for data
beginning year y (last digit
of year), day ddd, hour H,
minute mm
ydddHmmN.LBL PDS detached label for
the above file
To locate specific data files within the volume, users may consult
INDEX.TAB in the INDEX directory. To search for occultations captured under
certain conditions (solar zenith angle, latitude, season, etc.) users should
sort the 812506AA.OCS file in the OCS directory. To find occultations meeting
certain signal-to-noise ratio or observing criteria, sorting the OCCLOG.TAB
files in the DOCUMENT directory may be the most appropriate strategy.
==============================================================================
ERRATA
==============================================================================
A cumulative list of notes, warnings, and known errors is maintained in
the ERRATA.TXT file at the root level of each volume. ERRATA.TXT in the
initial release of this volume will have little content, however.
==============================================================================
FILE FORMAT
==============================================================================
All data files on the disc are accompanied by detached PDS labels, which
describe their contents. PDS TEXT objects have attached labels.
Detached labels have the same file name as the data file except that the
label name has the suffix "LBL". The label fully describes the format and
content of its associated file. Detached labels use pointers to reference
the data file -- for example,
^IMAGE = "JGM50C01.IMG"
points to JGM50C01.IMG, which contains the actual image described by the
label. Some data files contain more than one structure. For example,
^RSED_HDR_TABLE = ("8358D47A.EDS",1)
^RSED_TABLE = ("8358D47A.EDS",6)
are pointers to the file 8358D47A.EDS which contains two tables, one
beginning at record 1 and one beginning at record 6. Additional documentation
on all data file types is available in the Volume Software Interface
Specification in the DOCUMENT directory.
Text files, including data files of ASCII text and all labels (*.LBL
files) and tables (*.TAB files), are delimited with carriage-return (ASCII 13)
line-feed (ASCII 10) pairs at the end of each line.
In a departure from the practice in the original MGS-M-RSS-5-SDP-V1.0
archive, detached labels generally do NOT have fixed length records (of 80
bytes). This change was instituted to reduce the total volume of the EDS
directory. Text and catalog files (*.TXT and *.CAT, respectively) do have
fixed length records of 72 or 80 bytes, ending with a carriage-return
line-feed pair.
==============================================================================
CITATIONS
==============================================================================
Users wishing to cite products in this volume should use the following
volume information:
Author: D.P. Hinson
Editor: R.A. Simpson
Volume Name: Mars Global Surveyor Radio Occultation Profiles of
the Ionosphere - Reorganized
Volume: USA_NASA_JPL_MORS_1102
Data Set ID: MGS-M-RSS-5-EDS-V1.0
Publisher: NASA Planetary Data System
Year: 2008
==============================================================================
ACKNOWLEDGMENTS
==============================================================================
These data were collected under auspices of the Mars Global Surveyor
Project. G. Leonard Tyler of Stanford University was the Radio Science Team
Leader. Members of the Team and its support elements involved in data
acquisition and validation included Patricia Priest, Sami Asmar, Aseel
Anabtawi, Elias Barbinis, Paula Eshe, Danny Kahan, Alex Konopliv, Frank
Lemoine, William Sjogren, Tim Smith, and Joe Twicken. At PDS the assistance
of Ed Guinness, Lyle Huber, Betty Sword, and Joel Wilf was appreciated.
The data archive was reorganized into its present form at PDS PPI.
==============================================================================
DISCLAIMER
==============================================================================
Although considerable care has gone into making this volume set, errors
are possible. Reports of errors or difficulties would be appreciated. Please
contact one of the persons listed below.
==============================================================================
COGNIZANT PERSONNEL
==============================================================================
David Hinson was the lead scientist for radio occultation studies on the
MGS Radio Science Team and was primarily responsible for extracting the
electron density profiles from the raw data; he also reorganized the data for
this volume. Dick Simpson, MGS Radio Science Team Experiment Engineer,
assembled the volume. G. Leonard Tyler was the Leader of the MGS Radio
Science Team. The present form of the archive was produced from the
original CD-WO archive at the PPI Node of the PDS.
David P. Hinson
Center for Radar Astronomy
Packard Building - Room 333
350 Serra Mall
Stanford University
Stanford, CA 94305
Tel: 650-723-3534
FAX: 650-723-9251
dhinson@stanford.edu
or
David P. Hinson
SETI Institute
515 North Whisman Rd
Mountain View, CA 94043
Tel: 650-810-0217
dhinson@seti.org
Richard A. Simpson
Center for Radar Astronomy
Packard Building - Room 332
350 Serra Mall
Stanford University
Stanford, CA 94305
Tel: 650-723-3525
FAX: 650-723-9251
rsimpson@magellan.stanford.edu
G. Leonard Tyler
Center for Radar Astronomy
Packard Building - Room 331
350 Serra Mall
Stanford University
Stanford, CA 94305
Tel: 650-723-3535
FAX: 650-723-9251
len.tyler@stanford.edu
PPI Node of the PDS:
PDS Operator
c/o Dr. Raymond Walker
3845 Slichter Hall
UCLA - IGPP
Los Angeles, CA 90095-1567
Tel: (310) 206-6073
pds_operator@igpp.ucla.edu
==============================================================================
ACRONYMS AND ABBREVIATIONS
==============================================================================
CD Compact Disc
HGA High-Gain Antenna
MGS Mars Global Surveyor
OCS Occultation Summary File (standard resolution products)
PDS Planetary Data System
RSS Radio Science Subsystem
RST Radio Science Team
SDP Science Data Products
SIS Software Interface Specification
T-p Temperature-pressure
TPS Temperature-Pressure Profile (standard resolution)
WO Write Once
|