PDS_VERSION_ID = PDS3
LABEL_REVISION_NOTE = "
2001-04-06, R. Simpson, initial draft;
2002-09, S. Joy, added Io target object;
2003-08-18, S. Joy, minor revisions requested at peer review;"
RECORD_TYPE = FIXED_LENGTH
RECORD_BYTES = 72
OBJECT = DATA_SET
DATA_SET_ID = "GO-J-RSS-5-ROCC-V1.0"
OBJECT = DATA_SET_INFORMATION
DATA_SET_NAME = "GLL RPT IONOSPHERE PROFILES"
DATA_SET_COLLECTION_MEMBER_FLG = "N"
START_TIME = 1995-12-08T10:00:00Z
STOP_TIME = 1997-08-03T22:10:10Z
DATA_SET_RELEASE_DATE = 2000-09-30
PRODUCER_FULL_NAME = "DAVID P. HINSON"
DETAILED_CATALOG_FLAG = "N"
ARCHIVE_STATUS = "LOCALLY ARCHIVED"
DATA_OBJECT_TYPE = TABLE
CITATION_DESC = "
Hinson, D.P.,GLL RPT IONOSPHERE PROFILES,
GO-J-RSS-5-ROCC-V1.0, NASA Planetary Data System, 2000"
ABSTRACT_DESC = "
The Galileo Radio Propagation Team Ionosphere Profile data set
is small number of electron density profiles derived from radio
occultation data collected while Galileo was in Jupiter orbit.
Each profile is an ASCII table giving electron density as a
function of radius (and altitude). This data set contains
Jupiter profiles from 1995-1996 and Io profiles from 1997."
DATA_SET_TERSE_DESC = "
Galileo Jupiter and Io ionosphere electron density profiles from
radio occultation 1995-1997."
DATA_SET_DESC = "
Data Set Overview
=================
The Galileo Radio Propagation Team Ionosphere Profile data set
is small number of electron density profiles derived from radio
occultation data collected while Galileo was in Jupiter orbit.
Each profile is an ASCII table giving electron density as a
function of radius (and altitude). This data set contains
Jupiter profiles from 1995-1996 and Io profiles from 1997.
For more information see [HINSONETAL1997], [HINSONETAL1998A],
and [HINSONETAL1998B].
Parameters
==========
For Jupiter electron density profiles are tables of electron
density (and its uncertainty) versus radial distance from
Jupiter's center of mass to the closest approach of the ray
path, altitude of the closest point on the ray path above the
one-bar pressure level; planetocentric north latitude; and
planetocentric east longitude (System III).
For Io electron density profiles are tables of electron density
(and its uncertainty) versus radial distance from Io's center
of mass to the closest approach of the ray path, altitude of
the closest point on the ray path above the surface (reference
radius); planetocentric north latitude; and planetocentric east
longitude in body fixed coordinates.
A header record prepended to each table provides information
on observing times and geometry and on files used in the data
processing.
Processing
==========
Ionosphere electron density profiles were derived from raw
receiver output in several steps.
First, deterministic sources of frequency change were
identified and removed coherently. These included motion
of the spacecraft, motion of the Earth receiving station,
drift of the UltraStable Oscillator (USO), and relativistic
effects associated with gravity fields of solar system
bodies. This left the carrier signal at a known frequency
except for phase drift associated with passage of the radio
ray through the ionosphere.
Second, using an accurate reconstruction of the spacecraft
trajectory, the phase of the signal versus time was converted
into a measure of refraction angle versus impact parameter --
the perpendicular distance between the incoming raypath and
the center of curvature of the atmosphere.
Third, the index of refraction versus radius was obtained
using an Abel inversion [FJELDBOETAL1971]. Refractive index
versus radius was converted to density of free electrons
versus radius using a method described by [YEH&LIU1972].
For more information [HINSONETAL1997], [HINSONETAL1998A], and
[HINSONETAL1998B].
Data
====
Ionosphere electron density profiles are stored in the EDS
directory.
File names for the Jupiter data are of the form Jnn_ddsC.EDS
where nn denotes the Jupiter orbit on which the data were
acquired (starting from 00), dd is the number of the NASA
Deep Space Network station collecting the data (14, 43, or 63),
s is the sense of the occultation ('N' for entry, 'X' for
exit), and C is a character indicating the version of the
file (A, B, etc.).
File names for the Io data are of the form InnoddsC.EDS where
nn denotes the Jupiter orbit on which the data were acquired
(starting from 00), o is the occultation number at Io (1-6),
dd is the number of the NASA Deep Space Network station
collecting the data (14, 43, or 63), s is the sense of the
occultation ('N' for entry, 'X' for exit), and C is a character
indicating the version of the file (A, B, etc.).
Ancillary Data
==============
None.
Coordinate System
=================
Close approach points of the Jupiter ray path are given in
System III latitude and east longitude. Close approach points
for the Io ray path are given in body fixed IAU 1994
coordinates [DAVIESETAL1995].
Software
========
None.
Media/Format
============
The archival data set were written on CD-WO media using the
Sun Ultra-5/Yamaha/GEAR CD authoring subsystem provided by
the Mars Global Surveyor Project. The CD-WO volume conforms
to ISO 9660 standards."
CONFIDENCE_LEVEL_NOTE = "
Overview
========
Data in this archive have been reduced as part of mission data
analysis activities of the GLL Radio Propagation Team.
Review
======
This archival data set was reviewed by the GLL Radio
Propagation Team and was posted on its web site
http://nova.stanford.edu/projects/gll/
prior to submission to the Planetary Data System (PDS).
PDS then conducted its own review.
Data Coverage and Quality
=========================
Ionosphere electron density profiles were derived from data
collected using the Galileo Orbiter low-gain antenna. As a
result, signal strengths are weak.
Coverage is shown in the tables below:
Galileo Radio Occultation Experiments at Jupiter
Date Orbit DSS Sense Location SZA LTST EDS File Name
---------- ----- --- ----- ----------- ---- ---- -------------
1995-12-08 00 63 N 24S, 292E 88.6 18.0 J00_63NA.EDS
1995-12-08 00 63 X 43S, 332E 91.0 5.7 J00_63XA.EDS
1996-11-08 03 43 N 28S, 102E 82.2 17.4 J03_43NA.EDS
1996-12-21 04 14 N 23S, 246E 86.3 17.8 J04_14NA.EDS
1996-12-22 04 43 X 25S, 167E 93.8 5.7 J04_43XA.EDS
Orbit is Galileo Jupiter orbit number, starting from 00.
DSS is DSN antenna number.
Sense is 'N' for entry occultation, 'X' for exit.
Location is planetocentric north latitude and east longitude
(System III) in degrees for the closest point on the ray path
SZA is solar zenith angle in degrees,
LTST is Local true solar time in hours.
Galileo Radio Occultation Experiments at Io
Date Occ DSS Sense Location Beta Io Lon EDS File Name
---------- --- --- ----- --------- ---- ------ -------------
1997-02-26 1 14 N 1N, 73W 163 260.0W I06114NA.EDS
1997-02-26 1 14 X 1N, 253W 17 262.0W I06114XA.EDS
1997-07-30 2 63 N 50N, 157W 105 49.1W I09263NA.EDS
1997-07-30 2 63 X 49N, 338W 76 51.3W I09263XA.EDS
1997-07-30 3 14 N 2S, 34W 124 234.6W I09314NA.EDS
1997-07-30 3 14 X 3S, 215W 55 238.1W I09314XA.EDS
1997-07-30 3 43 N 5S, 34W 124 234.6W I09343NA.EDS
1997-07-30 3 43 X 6S, 215W 55 238.1W I09343XA.EDS
1997-07-31 4 43 N 34N, 115W 139 10.3W I09443NA.EDS
1997-07-31 4 43 X 34N, 296W 42 11.6W I09443XA.EDS
1997-08-03 6 63 N 37S, 52W 129 1.5W I09663NA.EDS
1997-08-03 6 63 X 37S, 232W 51 3.0W I09663XA.EDS
Occ is occultation number (1-6); occultation 5 was a grazing
near miss at Io's south pole.
DSS is DSN antenna number.
Sense is 'N' for entry occultation, 'X' for exit.
Location is planetocentric north latitude and west longitude
(IAU 1994) in degrees for the closest point on the ray path
Beta is angle from center of upstream hemisphere (0N,270W)
in degrees.
Io Lon is longitude at sub-Io point on Jupiter in degrees
(System III).
Limitations
===========
None."
END_OBJECT = DATA_SET_INFORMATION
OBJECT = DATA_SET_TARGET
TARGET_NAME = JUPITER
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = IO
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_HOST
INSTRUMENT_HOST_ID = GO
INSTRUMENT_ID = RSS
END_OBJECT = DATA_SET_HOST
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "DAVIESETAL1995"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "FJELDBOETAL1971"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "HINSONETAL1997"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "HINSONETAL1998A"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "HINSONETAL1998B"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "YEH&LIU1972"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
END_OBJECT = DATA_SET
END