PDS3_DATA_SET_ID = VG2-J-MAG-4-SUMM-HGCOORDS-48.0SEC-V1.0 DATA_SET_NAME = VG2 JUP MAG RESAMPLED HELIOGRAPHIC (RTN) COORDS 48.0SEC V1.0 START_TIME = 1979-06-20T00:00:00.334 STOP_TIME = 1979-08-18T23:59:56.143 ORIGINAL_DATA_SET_RELEASE_DATE = 1997-12-01 PRODUCER_FULL_NAME = NESS, N. F. DATA_SET_SOURCE = NATIONAL SPACE SCIENCE DATA CENTER References: Behannon, K.W., L.F. Burlaga, and N.F. Ness, The Jovian Magnetotail and Its Current Sheet, J. Geophys. Res., Vol. 86, p. 8385, 1981. Connerney, J.E.P., M.H. Acuna, and N.F. Ness, Modeling the Jovian Current Sheet and Inner Magnetosphere, J. Geophys. Res., Vol. 86, p. 8370, 1981. Lepping, R.P., L.F. Burlaga, L.W. Klein, J. Jessen, and C.C. Goodrich, Observations of the Magnetic Field and Plasma Flow in Jupiter's Magnetosheath, J. Geophys. Res., Vol. 86, p. 8141, 1981. Ness, N.F., M.H. Acuna, R.P. Lepping, L.F. Burlaga, K.W. Behannon, and F.M. Neubauer, Magnetic Field Studies at Jupiter by Voyager 2: Preliminary Results, Science, Vol. 206, p. 966, 1979. DATA SET DESCRIPTION Data Set Overview ================= This data set includes Voyager 2 Jupiter encounter magnetometer data given in Heliographic coordinates and averaged from the 60 ms instrument sample rate to a 48 second resampled rate. The data set consists of the following columns: 1) UT of the sample in the format yyyy-mm-ddThh:mm:ss.sssZ, 2-4) spacecraft clock (m65536, mod60, fds-line), 5) magnetometer id (1 = LFM, 2 = HFM), 6) Br (radial, Sun to spacecraft, B-field component), 7) Bt (azimuthal B-field component, positive in the direction of planetary orbital motion), 8) Bn (North/South B-field component, positive northward), 9) Bmag (magnitude of the averaged components), 10) avg_Bmag (average of the magnetic field magnitudes), 11) delta (latitude = arcsin(Bn/Bmag)), 12) lambda (longitude = 180. - atan(Bt/Br)), 13-15) rms vector, 16) npts (number of points in average), 17) data flag. - a flag value that indicates either software error or spacecraft hardware interference reduced confidence in this record (flag value of 1 is bad , 0 is good or unchecked). All magnetic field observations are measured in nanoTesla. All of the magnetic field data are calibrated (see the instrument calibration description for more details). [Note that the magnetic field vector descriptions given above are best at lower latitudes, including all latitudes reached by Voyager during the Jupiter encounter] Parameters ========== PARAMETER RESOLUTION DESCRIPTION NAME (UNITS) time 48 Sec time of the sample (UT) in the format yyyy-mm-ddThh:mm:ss.sssZ. The full sampling rate for the instrument is .06 +/- .006 sec. m65536, (counts) s/c clock mod 65536, mod 60 and mod60 and fds line fds_line mag_id n/a magnetometer ID magnetic (nT) measured parameter equaling the field magnetic field strength (e.g. in components nanoTeslas) along a particular axis (Br, Bt, Bn) direction. Usually the three orthogonal axis components are measured by three different sensors. magnetic (nT) derived parameter which combines the 3 field vector orthogonal magnetic field component (Bmag, avg_Bmag) measurements. delta n/a delta = arcsin(Bn/Bmag) lambda n/a lambda = 180. - atan(Bt/-Br) rms_Br, Pythagorean root mean square deviation rms_Bt, and of the magnetic component averages rms_Bn npts (counts) the number of data points in the current average dflag n/a a character string which indicates software or s/c hardware intervention which reduces confidence in the data (NULL flags represent 'good' data) Ancillary Data ============== An ancillary data file containing the derived spacecraft magnetic field is provided with this data at a 48 second sample rate. These data provide zero level offsets used in the data processing. S/C field data is provided in spacecraft coordinates as follows: PARAMETER RESOLUTION DESCRIPTION NAME (UNITS) time 48 sec time in format yyyy-mm-ddThh:mm:ss.sssZ m65536 n/a s/c clock mod 65536 mod60 n/a s/c clock mod60 mag_id n/a magnetometer ID Bx (nT) spacecraft coords. X component By (nT) spacecraft coords. Y component Bz (nT) spacecraft coords. Z component Bmag (nT) total magnetic field strength rms_Bx (nT) rms mag component rms_By (nT) rms mag component rms_Bz (nT) rms mag component npts (counts) number of points in average Data Coverage ============= Filename Records Start Stop ------------------------------------------------------------------- Volume ID: VG_1502 HG_48S.TAB 91855 1979-06-20T00:00:00.334Z 1979-08-18T23:59:56.143Z CONFIDENCE LEVEL NOTE Confidence Level Overview ========================= This data set contains some data gaps and spikes. The data set does contain a flag value which has been provided by the PI (Norman Ness) that indicates whether or not a particular record has been contaminated by software error or by spacecraft interference (a flag value of 1 indicates a bad value, 0 indicates that the record has either not been evaluated or is good). Some records that are obviously contaminated have not been flagged. The hourly summary data will show a contamination code and data quality code of 2 when data in the hour have not been flagged but are obviously in error and a contamination code of 1 when the hour contains flagged records. Missing Data Flag ================= Any data column whose value is -9.99999999e+10 is a missing data value.