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