PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = "Mark Vincent, May 2000" RECORD_TYPE = STREAM OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 1999-07-16 NOTE = "ASCII description of ASI files" END_OBJECT = TEXT END Description of Atmosphere Structure Instrument files in the data bank: This file describes the data obtained by the Galileo Probe Atmosphere Structure Instrument during the entry and descent into the Jupiter atmosphere on December 7, 1995. The total time of data acquisition was less than two hours before the destruction of the probe in the Jupiter atmosphere. See errata.txt for a description of ASI related files that are not listed below. File asi_cal.txt =================== This file provides an instrument overview and describes the calibration of the individual sensors. File upperatm.dat =================== This file contains reduced data for the Galileo Probe Atmospheric Structure Instrument, including time from minor frame 0, altitude, pressure, temperature, atmospheric density, mean molecular weight, ratio of specific heats, gas constant, probe velocity, flight path angle, latitude and longitude for the entry phase. File descent.dat =================== This file contains reduced data for the Galileo Probe Atmospheric Structure Instrument, including time from minor frame 0, altitude, pressure, temperature, atmospheric density, gravitational acceleration, descent velocity, and temperature gradient for the descend phase. These profiles are not a list of measured points, but is derived using the dry adiabat which fits the data, as shown and described in SEIFFETAL1998. Data in the following files d04p1.dat, d04p2.dat and d04p3.dat, contain data for all of the Descent sequence pressure sensor measurements. The data in file d04p1 contains all data from the 0 to 500 mb range sensor. The data in file d04p2 contains all data from the 0 to 4 b range sensor. The data in file d04p3 contains all data from the 0 to 28 b range sensor. A correction (reduction in pressure) needs to be made for the ram effect of the probe moving through the atmosphere for each set of pressure sensor data. The magnitude of this correction depends upon the velocity profile developed by modeling the descent. For one modeling approach the correction is about -5mb for the bulk of descent, with some modest variations during the first 100 seconds which reach a peak of about -7.8 mb at 80 sec. Descriptions of the instrumentation can be found in [SEIFFETAL1996] Space Sciences Review, Volume 60, May 1992, pages 203 - 232. File d04p1.dat =================== This file comprises three columns: column 1 contains sensor sampling time in seconds after the start of the Descent mode, column 2 contains the measured pressure data in millibars, and column 3 contains the sensor temperature in degrees Celsius. There are no corrections required to this sensor data for rate of change of temperature effects. File d04p2.dat =================== This file comprises five columns: column 1 contains sensor sampling time in seconds after the start of the Descent mode, column 2 contains the pressure derived from the steady state sensor calibrations in millibars, column 3 contains the correction for the rate of change of temperature effect on the sensor in millibars, column 4 contains the computed final pressure data in millibars, and column 5 contains the sensor temperature in degrees Celsius. File d04p3.dat =================== This file comprises five columns: column 1 contains sensor sampling time in seconds after the start of the Descent mode, column 2 contains the pressure derived from the steady state sensor calibrations in millibars, column 3 contains the correction for the rate of change of temperature effect on the sensor in millibars, column 4 contains the computed final pressure data in millibars, and column 5 contains the sensor temperature in degrees Celsius. Spikes in pressure data after ~2600 sec are instrument anomalies [SEIFFETAL1998]. File uncert.txt =================== Order of uncertainties in pressure data from table 4 in SEIFFETAL1998. File d05t1.dat =================== This file contains all data from the primary temperature sensor for the Descent sequence. File d05t2.dat =================== This file contains all data from the secondary temperature sensor for the Descent sequence. File accel.txt =================== This file provides a description of the acceleration measurements and their limitations. File e03an.dat ================== Lateral acceleration measurements for the Entry sequence. File e03z1.dat =================== Primary, or Z1, axial acceleration measurements for the Entry sequence. File e03z2.dat =================== Secondary, or Z2, axial acceleration measurements for the Entry sequence. File d06an.dat =================== Lateral acceleration measurements for the Descent sequence. File d06z1.dat =================== Primary, or Z1, axial acceleration measurements for the Descent sequence. File d06z2.dat =================== Secondary, or Z2, axial acceleration measurements for the Descent sequence. File hk02.dat =================== Instrument temperatures taken as part of housekeeping.