Data Set Information
|
DATA_SET_NAME |
VG2 SAT MAG RESAMPLED KRONOGRAPHIC (L1)
COORDS 1.92SEC V1.1
|
DATA_SET_ID |
VG2-S-MAG-4-RDR-L1COORDS-1.92SEC-V1.1
|
NSSDC_DATA_SET_ID |
|
DATA_SET_TERSE_DESCRIPTION |
Voyager 2 Magnetometer (MAG) data in Kronographic (L1) coordinates from the
Saturn encounter. The data set provides 1.92 second averages of the magnetic
field data.
|
DATA_SET_DESCRIPTION |
Data Set Overview
=================
This data set includes Voyager 2 Saturn encounter magnetometer
data from the Low Field Magnetometer (LFM) resampled at a 1.92 second
sample rate from the 60 msec instrument sampling rate. Data coverage
begins in the solar wind and continues until at least the first
magnetopause crossing. The data are given in Kronographic (L1)
coordinates. The data set is composed of the following columns:
1) time - UT of the sample in the format yyyy-mm-ddThh:mm:ss.sssZ,
2) spacecraft clock values (m65536:mod60:fds_line), 3) mag_id -
magnetometer id (1 = LFM, 2 = HFM), 4) Br - radial (Saturn to
spacecraft) B-field component, 5) Btheta - North/South (L1) B-field
component (positive southward), 6) Bphi - azimuthal (L1)
B-field component (positive eastward), 7) Bmag - magnitude of the
averaged magnetic field components, 8) avg_Bmag - average of the
magnetic field magnitudes, 9) delta - magnetic latitude =
arcsin(Btheta/Bmag), 10) lambda - longitude = 180. - atan(Bphi/-Br),
11-13) rms_br, rms_bt, and rms_bn - rms vectors, 14) npts - number
of points in average. All magnetic field observations are measured
in nanoTesla. All of the magnetic field data are calibrated (see the
instrument calibration description for more details). These data
are provided in a Saturn centered spherical system (L1), based on the
Saturn Longitude System (Voyager Measurements of the Rotation Period
of Saturn's Magnetic Field, Desch and Kaiser, JGR, 8, 253, 1981).
The the magnetic field components are:
BR - radial B-field component (along the Saturn to spacecraft
line) positive away from Saturn
BTHETA - North/South (L1) B-field component, positive southward
BPHI - azimuthal (L1) B-field component, positive eastward.
Processing Level Id : 4
Software Flag : Y
Processing Start Time : 1988-09-21
Parameters
==========
Sampling Parameter Name : TIME
Data Set Parameter Name : MAGNETIC FIELD VECTOR
Sampling Parameter Resolution : 1.920000
Minimum Sampling Parameter : 19770820120000.000000
Maximum Sampling Parameter : UNK
Sampling Parameter Interval : 1.920000
Minimum Available Sampling Int : 0.060000
Data Set Parameter Unit : NANOTESLA
Noise Level : 0.006000
Sampling Parameter Unit : SECOND
PARAMETER RESOLUTION DESCRIPTION
NAME (UNITS)
time 1.92 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, Btheta, direction. Usually the three
Bphi) 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(Btheta/Bmag)
lambda n/a lambda = 180. - atan(Bphi/-Br)
rms_Br, Pythagorean root mean square deviation
rms_Bt, and of the component averages
rms_Bp
npts (counts) the number of data points in the
current average
Source Instrument Parameters
============================
Instrument Host ID : VG2
Data Set Parameter Name : MAGNETIC FIELD VECTOR
Instrument Parameter Name : MAGNETIC FIELD COMPONENT
Important Instrument Parameters : 1
Instrument Host ID : VG2
Data Set Parameter Name : MAGNETIC FIELD VECTOR
Instrument Parameter Name : WAVE MAGNETIC FIELD INTENSITY
Important Instrument Parameters : 1
Processing
==========
Processing History
------------------
Source Data Set ID : N/A
Software : UNK
Product Data Set ID : VG2-S-MAG-4-1.92SEC
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 Bx component
rms_By (nT) rms By component
rms_Bz (nT) rms Bz component
npts (counts) number of points in average
|
DATA_SET_RELEASE_DATE |
1996-01-01T00:00:00.000Z
|
START_TIME |
1981-08-23T10:34:23.645Z
|
STOP_TIME |
1981-08-29T11:59:57.158Z
|
MISSION_NAME |
VOYAGER
|
MISSION_START_DATE |
1972-07-01T12:00:00.000Z
|
MISSION_STOP_DATE |
N/A (ongoing)
|
TARGET_NAME |
SATURN
|
TARGET_TYPE |
PLANET
|
INSTRUMENT_HOST_ID |
VG2
|
INSTRUMENT_NAME |
TRIAXIAL FLUXGATE MAGNETOMETER
|
INSTRUMENT_ID |
MAG
|
INSTRUMENT_TYPE |
MAGNETOMETER
|
NODE_NAME |
Planetary Plasma Interactions
|
ARCHIVE_STATUS |
ARCHIVED
|
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.
Data Coverage
=============
Filename Records Start Stop
----------------------------------------------------------------------
Volume ID: VG_1601
L1_1_92S.TAB 283201 1981-08-23T10:34:23.645Z 1981-08-29T23:59:57.158Z
Missing Data Flag
=================
Any data column whose value is 9999.999 is a missing data value.
|
CITATION_DESCRIPTION |
Ness, N.F., Connerney, J.E., Lepping, R.P.,
VG2-S-MAG-4-RDR-L1COORDS-1.92SEC-V1.1, VG2 SAT MAG
RESAMPLED KRONOGRAPHIC (L1) COORDS 1.92SEC V1.1,
NASA Planetary Data System, 1996.
|
ABSTRACT_TEXT |
This data set includes Voyager 2 Saturn
encounter magnetometer data from the Low Field Magnetometer (LFM)
resampled at a 1.92 second sample rate from the 60 msec instrument
sampling rate. Data coverage begins in the solar wind and continues
until at least the first magnetopause crossing. The data are given in
Kronographic (L1) coordinates. The data set is composed of the following
columns: 1) time - UT of the sample in the format
yyyy-mm-ddThh:mm:ss.sssZ, 2) spacecraft clock values
(m65536:mod60:fds_line), 3) mag_id - magnetometer id (1 = LFM, 2 = HFM),
4) Br - radial (Saturn to spacecraft) B-field component, 5) Btheta -
North/South (L1) B-field component (positive southward), 6) Bphi -
azimuthal (L1) B-field component (positive eastward), 7) Bmag -
magnitude of the averaged magnetic field components, 8) avg_Bmag -
average of the magnetic field magnitudes, 9) delta - magnetic latitude =
arcsin(Btheta/Bmag), 10) lambda - longitude = 180. - atan(Bphi/-Br),
11-13) rms_br, rms_bt, and rms_bn - rms vectors, 14) npts - number of
points in average. All magnetic field observations are measured in
nanoTesla. All of the magnetic field data are calibrated (see the
instrument calibration description for more details). These data are
provided in a Saturn centered spherical system (L1), based on the Saturn
Longitude System (Voyager Measurements of the Rotation Period of
Saturn's Magnetic Field, Desch and Kaiser, JGR, 8, 253, 1981).
|
PRODUCER_FULL_NAME |
NATIONAL SPACE SCIENCE DATA CENTER
|
SEARCH/ACCESS DATA |
Planetary Plasma Interactions Website
|
|