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PDS_VERSION_ID = PDS3
LABEL_REVISION_NOTE = "M.R. SHOWALTER, 2003-12-04"
RECORD_TYPE = STREAM
OBJECT = DATA_SET
DATA_SET_ID = "VG1/VG2-SR/UR-RSS-4-OCC-V1.0"
OBJECT = DATA_SET_INFORMATION
DATA_SET_NAME = "VG1/VG2 SR/UR RSS RESAMPLED
RING OCCULTATION V1.0"
ARCHIVE_STATUS = IN_PEER_REVIEW
DATA_SET_COLLECTION_MEMBER_FLG = Y
DATA_OBJECT_TYPE = SERIES
START_TIME = 1980-11-01T00:00:00
STOP_TIME = 1986-02-01T00:00:00
DATA_SET_RELEASE_DATE = 2003-12-31
PRODUCER_FULL_NAME = "MARK R. SHOWALTER"
DETAILED_CATALOG_FLAG = N
DATA_SET_TERSE_DESC = "
This data set contains highly processed ring profiles of the rings
of Saturn (Voyager 1) and Uranus (Voyager 2) produced by
transmitting 3.6 and 13 cm wavelength coherent signals through the
rings toward Earth."
DATA_SET_DESC = "
Data Set Overview
=================
This data set contains radio occultation data obtained during the
Voyager 1 Saturn encounter and the Voyager 2 Uranus encounter.
Only highly processed ring occultation data is included.
Ring profiles are archived in a variety of formats, from the
source files as provided to the Ring-Moon Systems Node to calibrated and
resampled optical depth profiles. Processing software, geometry
solutions and calibration models are also provided.
Parameters
==========
Data files contain ring normal opacity and phase shift of the
X-band (3.6 cm) and S-band (13 cm) signals as they passed through
the ring plane on their transit from Voyager to Earth.
Some files contain the complex transmissivity of the ring, which
is related to ring opacity and phase shift as follows:
tau = normal opacity
phi = phase shift
T_norm = exp(-tau/(2*mu0)) = amplitude of the transmissivity
T_re = T_norm * cos(phi) = real component of the transmissivity
T_im = T_norm * sin(phi) = imaginary component of the
transmissivity
Here mu0 is the cosine of the incidence angle.
Processing
==========
These data files are already highly processed, as summarized by
[MAROUFETAL1986] for Saturn and [GRESHETAL1989] for Uranus.
Further processing involves conventional resampling and smoothing.
Data
====
A variety of data files are included on this volume.
Source data (S_RINGS/SORCDATA and U_RINGS/SORCDATA directories)
---------------------------------------------------------------
The data files as contributed to the Ring-Moon Systems Node by several
investigators. These files are provided for documentation
purposes and are not otherwise supported.
Raw data (S_RINGS/RAWDATA and U_RINGS/RAWDATA directories)
----------------------------------------------------------
These files contain essentially the same data as are found in
the SORCDATA directory, but in easier to use, PDS-compliant
formats. Note that these are not raw in the conventional
sense---they are in fact highly processed. However they serve as
the raw materials from which the Ring-Moon Systems Node generated its
derived products.
Edited data (S_RINGS/EDITDATA and U_RINGS/EDITDATA directories)
---------------------------------------------------------------
Edited versions of the raw data, which in this case entails
conversion from opacity and phase to complex transmissivity. The
latter is more appropriate for smoothing and resampling.
Derived profiles (S_RINGS/EASYDATA and S_RINGS/EASYDATA dirs)
-------------------------------------------------------------
Easy-to-use ASCII data files containing ring opacity, phase and
their uncertainty vs. radial location in a ring system. Files
are included at a variety of radial resolutions. Because the
rings of Uranus are narrow and inclined, there are separate
profiles for each Uranian ring.
Ancillary Data
==============
Several different types of ancillary data files are provided to
describe the geometry and calibration during each occultation.
Geometry models (S_RINGS/GEOMETRY and S_RINGS/GEOMETRY dirs)
------------------------------------------------------------
ASCII data files, containing a description of the ring intercept
geometry, indexed to locations in the corresponding edited data
files. Because the rings of Uranus are inclined, there are
separate geometry files for each ring of these planets.
Calibration models (S_RINGS/CALIB and S_RINGS/CALIB directories)
----------------------------------------------------------------
ASCII data files, containing the modeled free space signal and
noise power, indexed to locations in the corresponding edited
data files.
Ephemeris files (SPICE directory)
---------------------------------
Voyager ephemeris files for each of the planetary encounters, in
SPICE format. For more information about SPICE data and toolkits,
consult the PDS Navigation and Ancillary Information Facility
(NAIF) Node at:
//pds.jpl.nasa.gov/naif.html
Coordinate System
=================
All geometric quantities appearing in the labels are in J2000
coordinates. In this coordinate frame, the z-axis points
northward along the Earth's J2000 rotation axis and the x-axis
points toward the First Point of Aries. In some cases, B1950
coordinate values are also included.
Software
========
Included on this disk is the source code for several libraries
of software tools designed to be used with this and other ring
occultation data sets.
Light Label Library (SOFTWARE/OAL directory)
--------------------------------------------
A toolkit supported by the PDS Central Node for reading and
writing PDS labels.
Object Access Library (SOFTWARE/OAL directory)
----------------------------------------------
A toolkit supported by the PDS Central Node for reading and
writing data objects described by PDS labels. Built atop the
Light Label Library.
Profile Library (SOFTWARE/PROFILE directory)
--------------------------------------------
A toolkit supported by the PDS Ring-Moon Systems Node for manipulating
one-dimensional profiles of planetary rings. Built atop the
Light Label Library and the Object Access Library.
Also included are the software tools to generate calibrated ring
profiles at arbitrary resolution. These are the tools used to
populate the EASYDATA subdirectories. These tools make full use of
the above libraries.
Media/Format
============
This data set is archived on compact disc (CDROM) media.
Organization and formats are according to PDS and ISO 9660
level 1 standards.
Binary data files are provided in native formats for most
platforms. Also, note that the software tools provided on this
volume handle binary conversions on the fly if this is necessary."
CONFIDENCE_LEVEL_NOTE = "
Confidence Level Overview
=========================
Models for the noise power in the data can be found in the
CALIB subdirectories. The ring profiles found in the EASYDATA
subdirectories include estimates of the 50% confidence interval on
opacity and phase.
Peer Review
===========
Peer review of this data set is in progress.
Data Coverage and Quality
=========================
The RSS experiments provided complete coverage of the ring systems
of Saturn and Uranus. At Uranus, both the ingress and egress
occultations of each ring were observed.
This data set does not include information about the regions
between the known Uranian rings."
END_OBJECT = DATA_SET_INFORMATION
OBJECT = DATA_SET_TARGET
TARGET_NAME = "S RINGS"
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = "U RINGS"
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_HOST
INSTRUMENT_HOST_ID = VG1
INSTRUMENT_ID = RSSVG1SE
END_OBJECT = DATA_SET_HOST
OBJECT = DATA_SET_HOST
INSTRUMENT_HOST_ID = VG2
INSTRUMENT_ID = RSSVG2UD
END_OBJECT = DATA_SET_HOST
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "GRESHETAL1989"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "MAROUFETAL1986"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
END_OBJECT = DATA_SET
END
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