Version:2.3.0
NumericalData
ResourceID
spase://NASA/NumericalData/Voyager2/MAG/VIM/ASCII/PT48S
ResourceHeader
ResourceName
Voyager 2 48-s Triaxial Fluxgate Magnetometer (MAG) Magnetic Field Data Near and Beyond Termination Shock in ASCII Format
ReleaseDate
2020-07-07 21:15:59Z
Description
The main science objectives for the VOYAGER interplanetary mission are as
follows:
- investigate the structure of the solar wind magnetic fields and plasma in the
inner and outer heliosphere;
- conduct long term study of heliospheric evolution during different phases of
the twenty-two year solar magnetic cycle and the eleven-year solar activity
cycle;
- study the long term solar modulation and determine the elemental and isotopic
abundances of galactic cosmic ray particles in the heliosphere;
- measure radial gradients, spectra, and nuclear abundances of the anomalous
component of cosmic rays from acceleration at the solar wind termination
shock;
- investigate local particle acceleration in the interplanetary medium from
solar flare shocks and corotating interaction regions;
- study propagation of solar energetic particles in the heliosphere.
The average magnetic field strength produced by the spacecraft at the location
of the outboard magnetometer of the dual magnetometers system on V2 and V2 is
about 0.1 - 0.2 nT, comparable to the most probable magnetic field strength in
the inner heliosheath and significantly larger than the most probable magnetic
field strength in the distant supersonic solar wind. The spacecraft magnetic
field is a complex, time-dependent signal that must be removed from the measured
magnetic field signal in order to derive the ambient magnetic fields of the
solar wind and heliosheath. Corrections must also be made for spurious magnetic
signals and noise associated with the telemetry system, ground tracking systems,
and other factors. Extracting the signal describing the solar wind and
heliosheath from the many sources of uncertainty is a complex and partly
subjective process that requires understanding of the instrument and judgment
based on experience in dealing with the ever-changing extraneous signals. We
estimate that for the V2 MAG data the 1-sigma the uncertainty the 48 sec
averages for each of the components of the magnetic field BR, BT, and BN is
typically +/- 0.02 nT; the uncertainty in magnitude F1 is typically +/- 0.03 nT.
F1, BR, BT, and BN can differ from one another and they may vary with time, but
there is no practical way to determine these uncertainties more precisely at
present.
References
Behannon, K.W., M.H. Acuna, L.F. Burlaga, R.P. Lepping, N.F. Ness, and F.M. Neubauer,
Magnetic-Field Experiment for Voyager-2 and Voyager-2, Space Science Reviews, 21 (3), 235-257, 1977.
Burlaga, L.F., Merged interaction regions and large-scale magnetic field fluctuations during 1991 -
Voyager-2 observations, J. Geophys. Res., 99 (A10), 19341-19350, 1994.
Burlaga, L.F., N.F. Ness, Y.-M. Wang, and N.R. Sheeley Jr., Heliospheric magnetic field strength and
polarity from 1 to 81 AU during the ascending phase of solar cycle 23, J. Geophys. Res., 107 (A11), 1410, 2002.
Ness, N., K.W. Behannon, R. Lepping, and K.H. Schatten, J. Geophys. Res., , 76, 3564, 1971.
Acknowledgement
Please acknowledge the Principal Investigator, N. Ness of University of Delaware and Co-Investigator L. Burlaga of NASA GSFC.
Contacts
InformationURL
Name
Readme at Voyager MAG team web site
URL
PriorIDs
spase://VSPO/NumericalData/Voyager2/MAG/VIM.PT48S
spase://VSPO/NumericalData/Voyager2/MAG/VIM/ASCII/PT48S
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
FTPS from SPDF (not with most browsers)
URL
Description
In ascii via ftp from SPDF
AccessURL
Name
HTTPS from SPDF
URL
Description
In ascii via HTTP from SPDF
Format
Text.ASCII
ProviderProcessingLevel
CALIBRATED
InstrumentIDs
MeasurementType
MagneticField
TemporalDescription
TimeSpan
StartDate
2009-01-31 11:01:29
StopDate
2014-12-30 21:11:57
Cadence
PT48S
ObservedRegion
Heliosphere.Outer
ObservedRegion
Heliosphere.Heliosheath
Caveats
Extracting the signal describing the solar wind and heliosheath from the many sources of uncertainty is a complex and
partly subjective process that requires understanding of the instrument and judgment based on experience in dealing with
the ever-changing extraneous signals. As a result, users should consult the specific caveats that are included in the header
of each granule. The granule headers list any caveats that are specific to that time interval.
Parameter #1
Name
Spacecraft ID
ParameterKey
Column_1
Description
Spacecraft ID. Value FLT1 means Voyager 1.
Support
Parameter #2
Name
Coordinate system
ParameterKey
Column_2
Description
Flag for coordinate system. Virtually all values are HG,
meaning Heliographic Inertial
Support
Parameter #3
Name
Year
ParameterKey
Column_3
Description
Year of the measurement, 2 digits
Support
Parameter #4
Name
Day of year
ParameterKey
Column_4
Description
Fractional day of year of the measurement (Jan 1 = 1).
ValidMin
1
ValidMax
366.9999
Support
Parameter #5
Name
B
ParameterKey
Column_5
Description
The magnetic field strength, the average of higher resolution field strengths, in nT
Units
nT
Field
Qualifier
Magnitude
Qualifier
Average
FieldQuantity
Magnetic
Parameter #6
Name
Average magnitude
ParameterKey
Column_6
Description
Magnitude of vector constituted by average field components
Units
nT
Field
Qualifier
Magnitude
Qualifier
Average
FieldQuantity
Magnetic
Parameter #7
Name
Field elevation angle
ParameterKey
Column_7
Description
Elevation angle of magnetic field vector
Units
Deg
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
RTN
ValidMin
-90.
ValidMax
90.
Field
Qualifier
DirectionAngle.ElevationAngle
Qualifier
Average
FieldQuantity
Magnetic
Parameter #8
Name
Field azimuth angle
ParameterKey
Column_8
Description
Azimuth angle of magnetic field vector
Units
Deg
CoordinateSystem
CoordinateRepresentation
Spherical
CoordinateSystemName
RTN
ValidMin
0.
ValidMax
360.
Field
Qualifier
DirectionAngle.AzimuthAngle
Qualifier
Average
FieldQuantity
Magnetic
Parameter #9
Name
Br
ParameterKey
Column_9
Description
Radial component of vector magnetic field in RTN coordinates.
Units
nT
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.I
Qualifier
Average
FieldQuantity
Magnetic
Parameter #10
Name
Bt
ParameterKey
Column_10
Description
Transverse component of vector magnetic field in RTN coordinates
Units
nT
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.J
Qualifier
Average
FieldQuantity
Magnetic
Parameter #11
Name
Bn
ParameterKey
Column_11
Description
Normal component of vector magnetic field in RTN coordinates
Units
nT
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.K
Qualifier
Average
FieldQuantity
Magnetic
Parameter #12
Name
dBr
ParameterKey
Column_12
Description
1-sigma uncertainty in the radial component of vector magnetic field in RTN coordinates.
Units
nT
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.I
Qualifier
StandardDeviation
FieldQuantity
Magnetic
Parameter #13
Name
dBt
ParameterKey
Column_13
Description
1-sigma uncertainty in the transverse component of vector magnetic field in RTN coordinates
Units
nT
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.J
Qualifier
StandardDeviation
FieldQuantity
Magnetic
Parameter #14
Name
dBn
ParameterKey
Column_14
Description
1-sigma uncertainty in the normal component of vector magnetic field in RTN coordinates
Units
nT
UnitsConversion
1e-9>T
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
RTN
Field
Qualifier
Component.K
Qualifier
StandardDeviation
FieldQuantity
Magnetic
Parameter #15
Name
X
ParameterKey
Column_15
Description
X component of HGI spacecraft position vector.
Units
AU
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
HGI
Support
Qualifier
Component.I
SupportQuantity
Positional
Parameter #16
Name
Y
ParameterKey
Column_16
Description
Y component of HGI spacecraft position vector.
Units
AU
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
HGI
Support
Qualifier
Component.J
SupportQuantity
Positional
Parameter #17
Name
Z
ParameterKey
Column_17
Description
Z component of HGI spacecraft position vector.
Units
AU
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
HGI
Support
Qualifier
Component.K
SupportQuantity
Positional
Parameter #18
Name
R
ParameterKey
Column_18
Description
Heliocentric radial distance of spacecraft.
Units
AU
Support
SupportQuantity
Positional