2.2.1 spase://VHO/NumericalData/Voyager2/MAG/PT48S Voyager 2 Magnetic Field Data Near and Beyond Termination Shock 2010-07-09T09:45:00Z The average magnetic field strength produced by the spacecraft at the location of the outboard magnetometer, of the dual magnetometers system on V2, varies between 0.1 and 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 the 1-sigma uncertainty in the 48 sec averages in the components of the magnetic field is typically +/- 0.02 nT. The uncertainties in 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. This descriptor, and the data access path identified below, are specific to 48s Voyager 2 MAG data taken when the spacecraft was in the vicinity of, and beyond, the heliospheric termination shock. 48s and 1hr ASCII data from Voyager 2 MAG, from earlier in the mission, are accessible at ftp://spdf.gsfc.nasa.gov/pub/data/voyager/voyager2/magnetic_fields/ 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-1 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. Please acknowledge the Principal Investigator, N. Ness of University of Delaware and Co-Investigator L. Burlaga of NASA GSFC. spase://SMWG/Person/Norman.F.Ness PrincipalInvestigator spase://SMWG/Person/Leonard.F.Burlaga CoInvestigator spase://SMWG/Person/Jan.Merka MetadataContact The Voyager web site http://voyager.jpl.nasa.gov spase://SMWG/Repository/NASA/GSFC/VHO-VMO Online Open http://vho.nasa.gov/mission/voyager/2/mag VHO repository of recent Voyager 2 MAG 48-second ascii data Text ASCII spase://SMWG/Instrument/Voyager2/MAG MagneticField 2007-08-31T00:00:00Z 2008-03-15T00:00:00 This data set is expected be updated. PT48S Heliosphere.Outer Heliosphere.Heliosheath 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. Spacecraft ID SC Spacecraft ID. Value 2 means Voyager 2. 2 2 Other Year year Year of the measurement Temporal Day of year DOY Fractional day of year of the measurement (Jan 1 = 1). 1 366.9999 Temporal B F1 The magnetic field strength, the average of higher resolution field strengths, in nT nT 1e-9>T Magnitude Average Magnetic Br BR Radial component of vector magnetic field in RTN coordinates. nT 1e-9>T Cartesian RTN Component.I Average Magnetic Bt BT Transverse component of vector magnetic field in RTN coordinates nT 1e-9>T Cartesian RTN Component.J Average Magnetic Bn BN Normal component of vector magnetic field in RTN coordinates nT 1e-9>T Cartesian RTN Component.K Average Magnetic dB dF1 1-sigma uncertainty in the magnetic field strength nT 1e-9>T Magnitude StandardDeviation Magnetic dBr dBR 1-sigma uncertainty in the radial component of vector magnetic field in RTN coordinates. nT 1e-9>T Cartesian RTN Component.I StandardDeviation Magnetic dBt dBT 1-sigma uncertainty in the transverse component of vector magnetic field in RTN coordinates nT 1e-9>T Cartesian RTN Component.J StandardDeviation Magnetic dBn dBN 1-sigma uncertainty in the normal component of vector magnetic field in RTN coordinates nT 1e-9>T Cartesian RTN Component.K StandardDeviation Magnetic