Minimize Level 1b Product Definitions


The Level 1b products of the Swarm mission contains time-series of quality-screen, calibrated, and corrected measurements given in physical, SI units in geo-localized reference frames. Level 1b products are provided individually for each of the three satellites Swarm A, Swarm B, and Swarm C on a daily basis. The Swarm Level 1b naming convention can be illustrated in the following example:

Level 1b example file name

Example illustrating the filename of the Swarm A Level 1b low-rate magnetic product MAGx_LR from 23 February 2013.

The following table identifies the Level 1b Products for Swarm. The Products with a daily period are provided covering one day of observations, i.e. 0:00:00 through 24:00:00 (UTC or GPS in case of RINEX files). The estimated sizes do not include header file information.

File Type File Description Rate Period Format Extension Estimated Size

[Mbytes/file]

MAGX_HR_1B Magnetic vector data, high rate ~50 Hz daily CDF .cdf 341
MAGX_LR_1B Magnetic data, low rate 1 Hz daily CDF .cdf 10.8
MAGX_CA_lB Magnetic Calibration data 1 Hz daily CDF .cdf 10.6
MAGXMAN_1B Magnetic Calibration Manoeuvre report < 1 month monthly CDF .cdf 10-3
EFIX_PL_1B Plasma data 2 Hz daily CDF .cdf 7.3
LP_X_CA_1B Langmuir Probe offset calibration data 6 h daily CDF .cdf 10-3
TIIX_CA_1B Thermal Ion Imager circular fit calibration data 1 day daily CDF .cdf 10-3
MODX_SC_1B Position and velocity 1 Hz daily ASCII .sp3 20.0
STRXATT_1B Attitude of spacecraft 1 Hz daily CDF .cdf 2.7
GPSXNAV_1B On-board GPSR navigational solution 1 Hz daily ASCII .sp3 12.7
GPSX_RO_1B GPS RINEX Observation data 0.1 Hz daily ASCII .rnx 86.9
GPSX_RN_1B GPS RINEX Navigation data 2 h daily ASCII .rnx 0.25
ACCX_PR_1B Pre-processed ACC data 1 Hz daily CDF .cdf 9.2
ASMXAUX_1B ASM auxiliary data 50 Hz daily CDF .cdf 19.6
VFMXAUX_1B VFM auxiliary data 50 Hz daily CDF .cdf 14.4

Table 1: Swarm Level 1b Products List

Magnetic Products

The primary Level 1b Products containing measurements of the magnetic field are MAGX_HR_1B and MAGX_LR_1B. They are largely identical with respect to the elements of the products, but the sampling rate of the data is different. MAGX_HR_1B is provided at the basic sampling rate of the vector magnetometer instrument (VFM), 50 Hz. This product is called Mag-H for short and is described in MAGX_HR_1B Product. The MAGX_LR_1B product contains magnetic vector data at a reduced sampling rate of 1 Hz plus the measurements of the magnetic field intensity from the scalar magnetometer (ASM) and is termed Mag-L for short. This is described in MAGX_LR_1B Product.

The magnetic vector elements of the MAGX_HR_1B and MAGX_LR_1B Products are provided in two reference frames: the VFM instrument frame and the orbit related NEC (North-East-Centre) frame. See [AD-7] for further details on these frames.

The magnetic Level 1b product named MAGX_CA_lB (Mag-C for short) contains the data used for the monitoring and estimation of the temporal VFM calibration parameters. Its content is described in MAGX_CA_1B Product. The temporal VFM parameters themselves are contained in an auxiliary data set, TCF.VFM, and stored in the magnetic products listed here. This Data Set is described in TCF.VFM Data Set.

The MAGXMAN_1B Product contains the report of the TCF.VFM records, their differences, and threshold checks when a magnetic calibration manouevre has been performed. See MAGXMAN_1B Product.

There are two additional magnetic products, ASMXAUX_1B and VFMXAUX_1B, containing the magnetic stray fields of the S/C at the ASM respectively the VFM sensor positions. They are used during special campaigns, e.g. when the ASM instrument is running in the special burst mode or vector mode configuration. Their contents are listed in ASMXAUX_1B Product and VFMXAUX_1B Product.

Early in the Swarm Mission it was recognized that the vector measurements on-board the Swarm spacecrafts suffered from an unexpected magnetic disturbance of varying strength and direction. Such disturbances are highly correlated with the Sun incident angle with respect to the spacecraft and are manifested as scalar residuals between the ASM and VFM data. The disturbance has been modelled as described in this technical note. Implemented from Product Baseline 04, the calibration parameters for the vector measurements estimated on a daily basis are replaced by the co-estimated calibration adjustment parameters, and the magnetic vector disturbance, denoted with dBSun and considered as a stray field vector, is then applied. The corrected data presents such additional parameter, dBSun. MAGx_CA_1B also contains the pre-calibrated (i.e. without any stray field correction applied) VFM magnetic data ("Bpre") and the reference angles "alpha" and "beta" which represent the Spacecraft to Sun attitude angles.

MAGX_HR_1B Product

The MAGX_HR_1B Product contains magnetic vector data at 50 Hz rate. The time instants of the data are determined by the VFM instrument samplings. No interpolation of the magnetic data is performed, neither to shift the measurements in time nor to fill any gaps in the VFM source data. The measurement data set record of the MAGX_HR_1B Product is described in Table 2. See also Mag-H Data Set Record, MDR_MAG_HR.

t Time, UTC
r Position of VFM sensor, ITRF, spherical coordinates (r, θ, φ)
BVFM Magnetic field vector, VFM frame
BNEC Magnetic field vector, NEC frame.

Note: this is set to zero if no attitude information is available (Flagsq = 255)

dBSun Sun induced stray magnetic field correction vector subtracted from measurements, VFM frame (implemented from Product Baseline 04).
dBAOCS AOCS magneto-torquer stray magnetic field correction vector subtracted from measurements, VFM frame.
dBother Stray magnetic field correction vector of all other sources subtracted from measurements, VFM frame.
Berror Error estimate on magnetic field vector, VFM frame.

Accounts for errors of commissioning including:

  • Instrument noise
  • Uncertainties in instrument calibration and characterisation
  • Uncertainties in corrections of stray fields from spacecraft

For further details please consult SW-TN-DTU-GS-016

qNEC←CRF Rotation from NEC to Common Reference Frame (CRF)
Atterror Error estimate on attitude information.

 

Includes effects such as number of STR camera heads supplying attitude information, possible discrepancies in provided attitude information from several heads, lack of STR attitude information (i.e. the attitude used for computing BNEC is obtained by interpolation over longer arcs of S/C motion), etc.

FlagsB Flags related to the magnetic field vector measurement
Flagsq Flags related to the attitude data
FlagsPlatform Flags related to the S/C platform – Bus and AOCS telemetry, position accuracy

Table 2: Measurement Data Set Record of MAGX_HR_1B Product

MAGX_LR_1B Product

The MAGX_LR_1B Product contains magnetic vector and scalar data at 1 Hz rate. The S/C data are processed to provide MAGX_LR_1B data at exact UTC seconds, i.e. both VFM vector and ASM scalar data are interpolated to yield these data. Hence, small gaps in the VFM or ASM data need not cause gaps in the product as the gaps may be filled by this interpolation. Any gaps, however, will have an impact on the error estimate of the associated product element. The measurement data set record of the MAGX_LR_1B Product is described in Table 3. See also Mag-L Data Set Record, MDR_MAG_LR.

t Time, UTC
r Position of VFM sensor, ITRF, spherical coordinates
F Magnetic field intensity ("scalar magnetic field")
dFAOCS AOCS magneto-torquer stray magnetic field intensity subtracted from scalar measurements
dFother Stray magnetic field intensity of all other sources subtracted from scalar measurements
Ferror Error estimate on magnetic field intensity.

Accounts for errors of commissioning including:

  • Instrument noise
  • Uncertainties in instrument calibration and characterisation
  • Uncertainties in corrections of stray fields from spacecraft
  • High frequency (ca 0.1 - 2 Hz) signal content

For further details please consult SW-TN-DTU-GS-016

BVFM Magnetic field vector, VFM frame.

Note: this is set to zero if insufficient vector magnetometer measurements are available (FlagsB = 255)

BNEC Magnetic field vector, NEC frame.

Note: this is set to zero if insufficient vector magnetometer or attitude measurements are available (FlagsB= 255 or Flagsq = 255)

dBSun Sun induced stray magnetic field correction vector subtracted from measurements, VFM frame (implemented from Product Baseline 04).
dBAOCS AOCS magneto-torquer stray magnetic field correction vector subtracted from vector measurements, VFM frame.
dBother Stray magnetic field correction vector of all other sources subtracted from vector measurements, VFM frame.
Berror Error estimate on magnetic field vector, VFM frame.

Accounts for errors of commissioning including:

  • Instrument noise
  • Uncertainties in instrument calibration and characterisation
  • Uncertainties in corrections of stray fields from spacecraft
  • High frequency (ca 2 - 12 Hz) signal content which is reduced in extraction of 1 Hz data from 50 Hz measurements

For further details please consult SW-TN-DTU-GS-016

QNEC←CRF Rotation from NEC to Common Reference Frame (CRF)
Atterror Error estimate on attitude information.

 

Includes effects such as number of STR camera heads supplying attitude information, possible discrepancies in provided attitude information from several heads, lack of STR attitude information (i.e. the attitude used for computing BNEC is obtained by interpolation over longer arcs of S/C motion), etc.

FlagsF Flags related to the magnetic field intensity measurement
FlagsB Flags related to the magnetic field vector measurement
Flagsq Flags related to the attitude data
FlagsPlatform Flags related to the S/C platform – Bus and AOCS telemetry, position accuracy
ASM_ Freq_Dev Deviation of actual ASM frequency calibration data from screened and filtered value

Table 3: Measurement Data Set Record of MAGX_LR_1B Product

MAGX_CA_1B Product

The MAGX_CA_1B Product contains magnetic vector and scalar data for monitoring, TCF.VFM verification, and calibration purposes. It contains raw as well as processed VFM vector measurements, VFM temperatures, and fully converted and corrected ASM measurements at 1 Hz rate. This is essentially the data used for the TCF.VFM estimation but including also the raw VFM data. The measurement data set record of the MAGX_CA_1B Product is described in Table 4. See also Mag-C Data Set Record, MDR_MAG_CA.

t Time, UTC
r Position, ITRF, spherical coordinates
F Converted and corrected magnetic field intensity from ASM – not adjusted for filter group delay
dFAOCS Stray magnetic field intensity correction of AOCS magneto-torquers
dFother Stray magnetic field intensity correction of all other sources.
Ferror Error estimate on magnetic field intensity.

Accounts for errors of commissioning including:

  • Instrument noise
  • Uncertainties in instrument calibration and characterisation
  • Uncertainties in corrections of stray fields from spacecraft

For further details please consult SW-TN-DTU-GS-016 observing that Ferror = F(3)err

FVFM Converted, corrected, ASM-filtered and interpolated magnetic field intensity from VFM – also corrected for ASM filter group delay
dtVFM Time offset, dtVFM = tout,VFMnear – tshifted, where tout,VFMnear is the time-stamp of the VFM sample nearest t shifted according to the ASM filter group delay (tshifted ≈ t ‑ 1.2 s)
B Converted and corrected magnetic field vector from VFM at time tshifted+dtVFM
dBSun Magnetic stray field vector of Sun induced stray field at VFM sensor at time tshifted+dtVFM (implemented from Product Baseline 04)
dBAOCS Magnetic stray field vector of AOCS magneto-torquer at VFM sensor at time tshifted+dtVFM
dBother Magnetic stray field vector of all other sources at VFM sensor at time tshifted+dtVFM
Bpre Pre-calibrated VFM magnetic field vector, VFM frame at time tshifted+dtVFM (implemented from Product Baseline 04)
EUVFM Raw VFM measurement at time tshifted+dtVFM
TCDC Temperature of VFM CDC at time tshifted+dtVFM
TCSC Temperature of VFM CSC at time tshifted+dtVFM
TEU Temperature of VFM electronic unit at time tshifted+dtVFM
alpha Solar inclination angle, rotation about -y axis, S/C frame at time tshifted+dtVFM (implemented from Product Baseline 04)
beta Solar inclination angle, angleto -y axis, S/C frame at time tshifted+dtVFM (implemented from Product Baseline 04)

Table 4: Measurement Data Set Record of MAGX_CA_1B Product

TCF.VFM Data Set

The TCF.VFM Data Set contains the parameters of the model of the temporal changes in the VFM instrument. The TCF.VFM Data Set Record shall be included in all three magnetic products: MAGX_HR_1B, MAGX_LR_1B, and MAGX_CA_1B. This data set contains one record per day and is described in Table 5 below. See also TCF.VFM Parameter Data Set Record, ASM_VFM_IC .

trange Time interval of the VFM measurements used in estimating the parameters
DPU_id Specifies the active VFM DPU (Data Processing Unit) identifier
Bias Vector of offsets
Scale Vector of scale values
Non‑orth Vector of non-orthogonality angles
Samples Number of samples used to estimate the parameters
Rms Weighted rms (root-mean-square) value of obtained misfit between VFM and ASM measurements
Cov Covariances of the estimated parameters
Wscale Log10 values of actual weigths of a-priori parameters (affected by e.g. maneouvers)

Table 5: TCF.VFM Data Set Record

MAGXMAN_1B Product

The MAGXMAN_1B Product contains a report on the VFM temporal parameters in response to a Magnetic Calibration manouevre stored in a VFM_MAN_RP Data Set (Table 6 below) as well as two TCF.VFM Data Set records (Table 5), the one from just before the manouevre and the one of the day of the manouevre.

Delta_bias Vector of changes in offsets
delta_scale Vector of changes in scale values
delta_non‑orth Vector of changes in non-orthogonality angles
Threshold1_bias Threshold 1 value for biases
Threshold1_scale' Threshold 1 value for scale values
Threshold1_non-orth Threshold 1 value for non-orthogonality angles
Threshold2_bias Threshold 2 value for biases
Threshold2_scale Threshold 2 value for scale values
Threshold2_non-orth Threshold 2 value for non-orthogonality angles
Messages Messages generated by the magnetic calibration manouevre processor

Table 6: MAGXMAN_1B VFM_MAN_RP Data Set Record

ASMXAUX_1B Product

The ASMXAUX_1B Product contains detailed information on the S/C magnetic stray fields at the ASM sensor position. The data are provided at 50 Hz at the time-instants of the VFM measurements (for internal practical purposes); the stray field vectors are provided in the ASM sensor frame. The measurement data set record of the ASMXAUX_1B Product is described in Table 7. See also ASMXAUX_1B Data Set Record, MDR_ASMAUX.

t Time, UTC
dBAOCS Magnetic stray field vector of AOCS magneto-torquer coils (including magnetically induced effects of this)
dBThrust Magnetic stray field vector of AOCS thruster activation
dBBattery Magnetic stray field vector of batteries charge/discharge currents
dBSP Magnetic stray field vector of solar panel currents
dBBus Magnetic stray field vector of S/C bus currents
dBVFM Magnetic stray field vector of VFM sensor

Table 7: Measurement Data Set Record of ASMXAUX_1B Product

VFMXAUX_1B Product

The VFMXAUX_1B Product contains detailed information on the S/C magnetic stray fields and the Sun induced stray field (implemented from Product Baseline 04) at the VFM sensor position. The data are provided at 50 Hz at the time-instants of the VFM measurements; the stray field vectors are provided in the VFM sensor frame. The measurement data set record of the VFMXAUX_1B Product is described in Table 8. See also VFMXAUX_1B Data Set Record, MDR_VFMAUX.

t Time, UTC
dBSun Magnetic stray field vector of Sun induced stray field (implemented from Product Baseline 04)
dBAOCS Magnetic stray field vector of AOCS magneto-torquer coils (including magnetically induced effects of this)
dBThrust Magnetic stray field vector of AOCS thruster activation
dBBattery Magnetic stray field vector of batteries charge/discharge currents
dBSP Magnetic stray field vector of solar panel currents
dBBus Magnetic stray field vector of S/C bus currents
dBSTR Static magnetic stray field vector of STR Camera Head Units (CHUs)
dBStatic Static magnetic stray field vector of rest of S/C
dBInd Magnetically induced stray field vector, from S/C
dBState Instrument and sub-system state dependent stray field vector, including latch valves

Table 8: Measurement Data Set Record of VFMXAUX_1B Product

Plasma Products

EFIX_PL_1B Product

The EFIX_PL_1B Product contains plasma data from the Electrical Field Instrument (EFI) which consists of the Langimur Probe (LP) and the Thermal Ion Imager (TII). The plasma product encompasses the electrical field vector, ion velocity as well as plasma density and temperature. Data is provided at 2 Hz rate. The time instants are determined by the EFI instruments. No interpolation of the EFI data is performed, neither to shift the measurements in time nor to fill any gaps.

The measurement data set record of the plasma product is listed in Table 9 below. See also Plasma Data Set Record, MDR_EFI_PL

t Time, UTC
r Position, ITRF, spherical geometric coordinates
vS/C S/C velocity, NEC frame
vion Ion velocity, NEC frame
vion,error Error estimate of vion, NEC frame
E Electric field vector, NEC frame
E'error Error estimate of E, NEC frame
dtLP Time offset of plasma density
n Plasma density
nerror Error estimate of n
Tion Plasma ion temperature
Tion,error Error estimate of Tion
Telec Plasma electron temperature
Telec,error Error estimate of Telec
US/C S/C potential
US/C,error Error estimate of US/C
vion,H Ion velocity from horizontal sensor
vion,H,error Error estimate of vion,H
vion,V Ion velocity from vertical sensor
vion,V,error Error estimate of vion,V
rmsfit,H RMS fit error from TII x-profile 2-Gaussian fits, H sensor
rmsfit,V RMS fit error from TII x-profile 2-Gaussian fits, V sensor
varx,H Variance in 16 Hz x moment, H sensor
vary,H Variance in 16 Hz y moment, H sensor
varx,V Variance in 16 Hz x moment, V sensor
vary,V Variance in 16 Hz y moment, V sensor
dvmtq,H Velocity deflection due to magnetotorquer, H sensor
dvmtq,V Velocity deflection due to magnetotorquer, V sensor
SAA South Atlantic Anomaly proximity indicator
FlagsLP Common flags of the LP data
FlagsLP,n Flags of the plasma density, n
FlagsLP,Telec Flags of the electron temperature, Telec
FlagsLP,Usc Flags of the S/C potential, US/C
FlagsTII Flags related to the TII measurements
FlagsPlatform Flags related to the S/C platform
Maneuver_Id Identification of actual S/C maneuver

Table 9: Measurement Data Set Records of EFIX_PL_1B Product

LP_X_CA_1B Product

The LP_X_CA_1B Product contains the TCF.LP Data Set records containing the LP calibration parameters determined in the Level 1b Processor from the Offset Determination Sweep Mode telemetry including the measurements themselves.

T Time of the LP Offset Determination Sweep
Probe1_I_Bias_Offset Probe 1 current bias offset determined
Probe1_I_Slope_Offset Probe 1 current slope offset determined
Probe1_I_Fit_Error Error in fit of Probe 1 current sweep data
Probe1_U_Bias_Offset Probe 1 voltage bias offset determined
Probe1_U_Slope_Offset Probe 1 voltage slope offset
Probe1_U_Fit_Error Error in fit of Probe 1 voltage sweep data
Probe2_I_Bias_Offset Probe 2 current bias offset
Probe2_I_Slope_Offset Probe 2 current slope offset
Probe2_I_Fit_Error Error in fit of Probe 2 current sweep data
Probe2_U_Bias_Offset Probe 2 voltage bias offset determined
Probe2_U_Slope_Offset Probe 2 voltage slope offset
Probe2_U_Fit_Error Error in fit of Probe 2 voltage sweep data
FP_I_Bias_Offset Face Plate current bias offset
FP_I_Slope_Offset Face Plate current slope offset
FP_I_Fit_Error Error in fit of Face Plate current sweep data
FP_U_Bias_Offset Face Plate voltage bias offset
FP_U_Slope_Offset Face Plate voltage slope offset
FP_U_Fit_Error Error in fit of Face Plate voltage sweep data
FP_I_offset Vector of Face Plate current offset measurements
FP_U_offset Vector of Face Plate bias offset measurements
P1_I_offset Vector of Probe 1 current offset measurements
P1_U_offset Vector of Probe 1 bias offset measurements
P1_ref_ADC2 Vector of Probe 1 reference ADC2
P1_ground Vector of Probe 1 ground
P2_I_offset Vector of Probe 2 current offset measurements
P2_U_offset Vector of Probe 2 bias offset measurements
P2_ref_ADC2 Vector of Probe 2 reference ADC2
P2_ground Vector of Probe 2 ground
P1_Slope Probe 1 slope offset, determined on-board
P1_Bias Probe 1 bias offset, determined on-board
P1_Error Probe 1 fit error, determined on-board
P2_Slope Probe 2 slope offset, determined on-board
P2_Bias Probe 2 bias offset, determined on-board
P2_Error Probe 2 fit error, determined on-board

Table 10: TCF.LP Data Set Record

TIIX_CA_1B Product

The TIIX_CA_1B Product contains one TCF.TII Data Set record which contains the TII circular fit calibration parameters determined from the nominal TII processing.

Trange Time interval of the TII data used in estimating the parameters
x0 Estimates of the x position of the image centers. Sensors H, V
y0 Estimates of the y position of the image centers.
Phi0 Estimates of mean azimuthal position of data points.
R0 Radius of best-fit circles
rms Goodness of fits (rms error)
Samples Number of data points used in fits
Success Flags indicating whether fits succeeded or not
r1 Average of r1
r1_r1 Averages of r1*r1
r1_y2 Averages of r1*y2
U_SC Average of US/C, spacecraft potential
dVgf Average of VG – VF, deflection minus faceplate voltage
Qram Average of (vS/Cvcr)2, ram-directed plasma flow, squared
r1_samples Numbers of samples used in averages

Table 11: TIIX_CA_1B TCF.TII Data Set Record

Position Products

The Swarm "position" Products consists of

  • RINEX files containing the GPSR data: GPSX_RO_1B and GPSX_RN_1B (RINEX Products)
  • Ephemeris products containing on-board navigational solution as well as medium precision orbit information and S/C orientation: GPSXNAV_1B, MODX_SC_1B, and STRXATT_1B (Ephemeris Products)
  • Pre-processed non-gravitional acceleration: ACCX_PR_1B (Acceleration Product).

RINEX Products

The GPSX_RO_1B and GPSX_RN_1B Products store GPSR data in the RINEX 3.00 format generally used for LEO satellites. The description of the format can be found in [RD-4] - rinex300.pdf. The contents of the two Products are:

  • GPSX_RO_1B: RINEX Observation data files
  • GPSX_RN_1B: RINEX Navigation message files

Ephemeris Products

The ephemeris information for Swarm is stored in three products:

  • GPSXNAV_1B: Position and velocity from the on-board navigational solution of the GPSR. Data Set Records are MDR_NAVSP3 which are SP3c format.
  • MODX_SC_1B: Position and velocity from the preliminary Medium Accuracy Orbit Determination (MOD). Data Set Records are MDR_MODSP3 which are SP3c format.
  • STRXATT_1B Attitude information at S/C level based on STR data. Data Set Records are MDR_SAT_AT, see Table 12.

See Position and Velocity Data Set Records, MDR_NAVSP3 and MDR_MODSP3 and Attitude Data Set Record, MDR_SAT_AT for detailed descriptions of the Products.

T Time, UTC
q Rotation from ITRF to S/C frame (from STR)
Flagsq Flags related to the S/C attitude information (q)
Maneuver_Id Identification of actual S/C maneuver

Table 12: S/C Attitude Measurement Data Set Record of STRXATT_1B Product

Acceleration Product

The ACCX_PR_1B Product contains pre-processed acceleration data. The data are not calibrated to the final level of accuracy as this is part of the Precise Orbit Determination (Level 2 processing).

The measurement data set record of the ACCX_PR_1B Product is given in Table 13 below. See also Acceleration Data Set Record, MDR_ACC_PR

t Time, UTC, ACC linear acceleration measurement time instants, time of angular acceleration measurement is approximately t - 0.12 s
a Pre-processed linear acceleration data, S/C frame
aang Pre-processed angular acceleration data, S/C frame
p Position of proof mass within ACC cavity
pang Angular position of proof mass within ACC cavity
Temp Temperatures of the ACC
VpLTC1043 Voltage of positive power source of LTC1043 (housekeeping info)
VnLTC1043 Voltage of negative power source of LTC1043 (housekeeping info)
Upol Polarization voltage
acentr* Centrifugal acceleration, S/C frame
aGG* Gravity gradient acceleration, S/C frame
aSun* Acceleration due to Solar radiation pressure, S/C frame
eSun Direction to the Sun, unit vector, S/C frame
AXxx Cross sections of the S/C, orbit frame, Xxx = head, down, left, right
KEarth Downward optical reflectivity normal
mS/C Mass of S/C
rCoG Position of CoG, S/C frame
PGas Pressure of gas tanks
TGas Temperature of gas tanks
Thru_Acc_On Accumulated thruster on time
FlagsACC Flags related to the ACC
FlagsPlatform Flags related to the S/C platform
The elements marked with an asterix (*) are correctional terms which may or may not
have been applied to (subtracted from) the data as indicated in FlagsACC.

Table 13: Measurement Data Set Record of ACCX_PR_1B Product

Details on Level 1b Product Data Set Records

This section contains the detailed definitions of the Swarm Level 1b Product Data Sets.

Generally, data are stored in binary format as signed or unsigned integers with suitable (decimal) scalings to accommodate the required range and resolution of the stored quantities. This provides a simple and efficient though flexible method of storing the data.

Latitude and longitude – provided as parts of geographical position information – ranges are symmetric around zero, i.e. latitude[-90..+90] and longitude[-180..+180].

The following sections contain Data Set Definition tables with the following entries:

Column

Description

FIELD Field name
DESCRIPTION Short description of the field
UNITS

Physical units of the field value:

 

eu = engineering units

m = meters

deg = degrees

as = arc seconds (1°/3600 ≈ 0.000278°)

nT = nano-Tesla (10-9 T)

C = degrees Celcius

s = seconds

UTC = Coordinated Universal Time

<blank> = no unit

 

DIM Dimensions of the stored values
TYPE

Type of stored integer value:

Type

Description

Range

CDF_UINT1

1 byte unsigned integer

0..255

CDF_INT2

2 byte signed integer

-32768..32767

CDF_UINT2

2 byte unsigned integer

0..65535

CDF_INT4

4 byte signed integer

-2147483648.. 2147483647

CDF_UINT4

4 byte unsigned integer

0..4294967295

Mag-H Data Set Record, MDR_MAG_HR

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of VFM), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

Latitude

Position in ITRF – Geomagnetic latitude

deg

1

CDF_DOUBLE

Longitude

Position in ITRF – Geomagnetic longitude

deg

1

CDF_DOUBLE

Radius

Position in ITRF – Radius

m

1

CDF_DOUBLE

B_VFM

Magnetic field vector, VFM frame

nT

3

CDF_DOUBLE

B_NEC

Magnetic field vector, NEC frame, zero if Flags_q = 255

nT

3

CDF_DOUBLE

dB_Sun

Magnetic stray field correction vector of Sun induced stray field, VFM frame (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

dB_AOCS

Magnetic stray field correction vector of AOCS magneto-torquer coils, VFM frame

nT

3

CDF_DOUBLE

dB_other

Magnetic stray field correction vector of all other sources, VFM frame

nT

3

CDF_DOUBLE

B_error

Error estimates on magnetic field, VFM frame

nT

3

CDF_DOUBLE

q_NEC_CRF

Quaternion, transformation: NEC ← CRF

 

4

CDF_DOUBLE

Att_error

Error estimates on attitude information

mdeg

1

CDF_DOUBLE

Flags_B

Flags characterizing the magnetic field measurement, see Table 14

 

1

CDF_UINT1

Flags_q

Flags characterizing the attitude information, see Table 14

 

1

CDF_UINT1

Flags_Platform

Flags characterizing the S/C platform information, see Table 14

 

1

CDF_UINT2


The values of the Flags_xxx fields of MDR_MAG_HR are given in the following table.

Flag

Value

Description

Flags_B

0

Magnetic field measurements (VFM) nominal

1

ASM instrument turned off

2

Outlier detected, gap, or not enough VFM temperature data for filtering

3

Both conditions (values) 1 and 2 above

4

Suspiciuos VFM sample

5-7

Combination (sum) of values 1-4

8

Discrepancy between ASM and VFM measurements

10,12,14

Combination (sum) of values 2, 4, and 8

Flags_q

0

Attitude information (STR) nominal

1

Lack of 1 or 2 attitudes of CHU1 in 4 nearest STR samples

2

Lack of 1 or 2 attitudes of CHU2 in 4 nearest STR samples

3

Lack of 1 or 2 attitudes of CHU3 in 4 nearest STR samples

4

Lack of 3 or 4 attitudes of CHU1 in 4 nearest STR samples

5

Lack of 3 or 4 attitudes of CHU2 in 4 nearest STR samples

6

Lack of 3 or 4 attitudes of CHU3 in 4 nearest STR samples

7

Not currently used

8

On-ground aberrational correction of any attitude sample among 4 nearest STR samples.

9-14

As 1-7 above with on-ground aberrational correction of any attitude sample among 4 nearest STR samples.

15

Not currently used

16

CHU1 obscured by bright object in 4 nearest STR samples (all 4 CHU1 samples invalid), CHU2 and CHU3 ok

17

CHU2 obscured by bright object in 4 nearest STR samples (all 4 CHU2 samples invalid) , CHU1 and CHU3 ok

18

CHU3 obscured by bright object in 4 nearest STR samples (all 4 CHU3 samples invalid) , CHU1 and CHU2 ok

19

Lack of 2-4 attitudes of CHU1 and CHU2 in 4 nearest STR samples, but not both simultaneously

20

Lack of 2-4 attitudes of CHU1 and CHU3 in 4 nearest STR samples, but not both simultaneously

21

Lack of 2-4 attitudes of CHU2 and CHU3 in 4 nearest STR samples, but not both simultaneously

22

Lack of 3-4 attitudes of CHU1, CHU2, and CHU3 in 4 nearest STR samples, but not two simultaneously

23

Not currently used

24-30

As 16-22 above with on-ground aberrational correction.

31

Not currently used

32

1 or 2 attitudes based on CHU1 alone (CHU2 and CHU3 missing) in 4 nearest STR samples

33

1 or 2 attitudes based on CHU2 alone in 4 nearest STR samples

34

1 or 2 attitudes based on CHU3 alone in 4 nearest STR samples

35

2 attitudes based on single, intermittent CHU alone in 4 nearest STR samples

36-39

Not currently used

40-43

As 32-35 above with on-ground aberrational correction.

44-47

Not currently used

48

1 attitude sample missing among 4 nearest STR samples (data gap)

49

2 attitude samples missing among 4 nearest STR samples

50

3 or more attitude samples missing among 4 nearest STR samples

51

3 or 4 attitudes based on CHU1 alone in 4 nearest STR samples

52

3 or 4 attitudes based on CHU2 alone in 4 nearest STR samples

53

3 or 4 attitudes based on CHU3 alone in 4 nearest STR samples

54

3 or 4 attitudes based on single, intermittent CHU alone in 4 nearest STR samples

55

Not currently used

56-62

As 48-54 above with on-ground aberrational correction.

63-254

Not currently used

255

Not enough STR data for generating attitude information.

Flags_Platform

0

Platform telemetry nominal (no missing or suspicious data)

1

Thruster latch valves open, thrusters not activated

2

Thrusters activated

4

Gap in Bus telemetry, 1 or 2 samples missing

5-7

Used for combinations (sum) of values 1, 2, and 4

8

Outlier detected in Bus currents

9-15

Used for combinations (sum) of values 1-8

16

Not enough data for filtering Bus currents (due to large gap or jump in data)

17-31

Used for combinations (sum) of values 1-16

32

Change in instrument state according to Bus telemetry

33-63

Used for combinations (sum) of values 1-32

64

No Bus telemetry available (for extended period)

65-67

Used for combinations (sum) of values 1, 2 and 64

128

Gap in AOCS telemetry

129-195

Used for combinations (sum) of values 1-67 and 128

256

Position information based on on-board (GPSR) navigational solution

257-323 384-451

Used for combinations (sum) of values 1-67, 128, and 256

Table 14: Flag Values of MDR_MAG_HR

Mag-L Data Set Record, MDR_MAG_LR

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of VFM), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

Latitude

Position in ITRF – Geocentric latitude

deg

1

CDF_DOUBLE

Longitude

Position in ITRF – Geocentric longitude

deg

1

CDF_DOUBLE

Radius

Position in ITRF – Radius

m

1

CDF_DOUBLE

F

Magnetic field intensity, zero if Flags_F = 255

nT

1

CDF_DOUBLE

dF_AOCS

Magnetic stray field correction intensity of AOCS magneto-torquer coils

nT

1

CDF_DOUBLE

dF_other

Magnetic stray field correction intensity of all other sources

nT

1

CDF_DOUBLE

F_error

Error estimate on magnetic field intensity

nT

1

CDF_DOUBLE

B_VFM

Magnetic field vector, VFM frame, zero if Flags_B = 255

nT

3

CDF_DOUBLE

B_NEC

Magnetic field vector, NEC frame, zero if Flags_B = 255 or Flags_q = 255

nT

3

CDF_DOUBLE

dB_Sun

Magnetic stray field vector of Sun induced stray field, VFM frame (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

dB_AOCS

Magnetic stray field correction vector of AOCS magneto-torquer coils, VFM frame

nT

3

CDF_DOUBLE

dB_other

Magnetic stray field correction vector of all other sources, VFM frame

nT

3

CDF_DOUBLE

B_error

Error estimates on magnetic field, VFM frame

nT

3

CDF_DOUBLE

q_NEC_CRF

Quaternion, transformation: NEC ← CRF

 

4

CDF_DOUBLE

Att_error

Error estimates on attitude information

mdeg

1

CDF_DOUBLE

Flags_F

Flags characterizing the magnetic field intensity measurement (F), see Table 15

 

1

CDF_UINT1

Flags_B

Flags characterizing the magnetic field vector measurement (B_VFM, B_NEC), see Table 15

 

1

CDF_UINT1

Flags_q

Flags characterizing the attitude information, see Table 14

 

1

CDF_UINT1

Flags_Platform

Flags characterizing the S/C platform information, see Table 14

 

1

CDF_UINT2

ASM_Freq_Dev

ASM frequency calibration data deviation

 

1

CDF_DOUBLE

The values of the Flags_q and Flags_Platform fields of MDR_MAG_LR are as for the MDR_MAG_HR given in Table 14; the values of Flags_F and Flags_B are given in the following table.

Flag

Value

Description

Flags_F

0

Magnetic field intensity measurements (ASM) nominal (scalar mode)

1

ASM running in vector mode

2

Outlier detected, gap, or not enough ASM frequency calibration data for filtering

3

Combination (sum) of values 1 and 2

4

At least one of 4 nearest ASM samples is suspicious

5-7

Combination (sum) of values 1-4

8

Within 8 seconds after ASM restart, loss of magnetic field lock, or telemetry gap

9-15

Combination (sum) of values 1-8

16

Discrepancy between ASM and VFM measurements – at least one of the 4 nearest ASM samples differ from VFM measurements

17-31

Combination (sum) of values 1-16

32

Gap in 4 nearest ASM samples

33-63

Combination (sum) of values 1-32

64

VFM instrument turned off, i.e. no stray field corrections

65-79 96-111

Combination (sum) of value 64 with values 1-15 and 32-47

255

Not enough ASM samples to generate F.

Flags_B

0

Magnetic field vector measurements (VFM) nominal

1

ASM instrument turned off

2

Outlier detected, gap, or not enough VFM temperature data for filtering

3

Both conditions (values) 1 and 2 above

4

More than 5 suspiciuos VFM samples in 2 seconds surrounding record time

5-7

Combination (sum) of values 1-4

8

Discrepancy between ASM and VFM measurements

10,12,14

Combination (sum) of values 2, 4, 8

16

Gap in VFM samples in surrounding 2 seconds (by rejection or missing data)

17-24 26,28,30

Combination (sum) of values 1, 2, 4, 8, and 16 (but not 1 and 8 simultaneously)

255

Not enough VFM samples to generate B_VFM and B_NEC

Table 15: Flags_F and Flags_B Values of MDR_MAG_LR

Mag-C Data Set Record, MDR_MAG_CA

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of VFM), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

Latitude

Position in ITRF – Geocentric latitude

deg

1

CDF_DOUBLE

Longitude

Position in ITRF – Geocentric longitude

deg

1

CDF_DOUBLE

Radius

Position in ITRF – Radius

m

1

CDF_DOUBLE

F

Magnetic field intensity, converted and corrected not adjusted for filter group delay

nT

1

CDF_DOUBLE

dF_AOCS

Magnetic stray field correction intensity of AOCS magneto-torquer coils

nT

1

CDF_DOUBLE

dF_other

Magnetic stray field correction intensity of all other sources

nT

1

CDF_DOUBLE

F_error

Error estimate on magnetic field intensity

nT

1

CDF_DOUBLE

F_VFM

Magnetic field intensity from the VFM instrument, converted and corrected

nT

1

CDF_DOUBLE

B

Magnetic field vector, VFM frame, time tshifted+dt

nT

3

CDF_DOUBLE

dB_Sun

Magnetic stray field correction vector of Sun induced stray field, VFM frame, time tshifted+dt_VFM (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

dB_AOCS

Magnetic stray field correction vector of AOCS magneto-torquer coils, VFM frame, time tshifted+dt_VFM

nT

3

CDF_DOUBLE

dB_other

Magnetic stray field correction vector of all other sources, VFM frame, time tshifted+dt_VFM

nT

3

CDF_DOUBLE

B_pre

Pre-calibrated VFM magnetic field vector, VFM frame, time tshifted+dt_VFM (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

EU_VFM

Raw VFM measuremet, time tshifted+dt_VFM

eu

3

CDF_DOUBLE

T_CDC

Temperature of VFM CDC, time tshifted+dt_VFM

°C

1

CDF_DOUBLE

T_CSC

Temperature of VFM CSC, time tshifted+dt_VFM

°C

1

CDF_DOUBLE

T_EU

Temperature of VFM EU, time tshifted+dt_VFM

°C

1

CDF_DOUBLE

dt_VFM

Time offset of VFM measurement

s

1

CDF_DOUBLE

alpha

Solar inclination angle, rotation about -y axis, S/C frame, time tshifted+dt_VFM (implemented from Product Baseline 04)

deg

1

CDF_DOUBLE

beta

Solar inclination angle, angleto -y axis, S/C frame, time tshifted+dt_VFM (implemented from Product Baseline 04)

deg

1

CDF_DOUBLE

TCF.VFM Parameter Data Set Record, ASM_VFM_IC

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

Timestamp_end

Time of last observation

UTC

1

CDF_EPOCH

Primary_EU

Id of active VFM DPU, 1 = primary, 3 = secondary

 

1

CDF_INT4

Bias

Vector of estimated offsets

nT

3

CDF_DOUBLE

Scale

Vector of estimated sensitivities

 

3

CDF_DOUBLE

Non_orth

Vector of estimated non-orthogonalities

mdeg

3

CDF_DOUBLE

Samples

Number of samples used in estimation

 

1

CDF_UNIT4

Rms

Weighted rms value of residuals after estimation

nT

1

CDF_DOUBLE

Cov_row1

Covariances of estimated parameters – lower left part of covariance matrix - row 1

 

1

CDF_DOUBLE

Cov_row2

Covariances of estimated parameters – lower left part of covariance matrix - row 2

 

2

CDF_DOUBLE

Cov_row3

Covariances of estimated parameters – lower left part of covariance matrix - row 3

 

3

CDF_DOUBLE

Cov_row4

Covariances of estimated parameters – lower left part of covariance matrix - row 4

 

4

CDF_DOUBLE

Cov_row5

Covariances of estimated parameters – lower left part of covariance matrix - row 5

 

5

CDF_DOUBLE

Cov_row6

Covariances of estimated parameters – lower left part of covariance matrix - row 6

 

6

CDF_DOUBLE

Cov_row7

Covariances of estimated parameters – lower left part of covariance matrix - row 7

 

7

CDF_DOUBLE

Cov_row8

Covariances of estimated parameters – lower left part of covariance matrix - row 8

 

8

CDF_DOUBLE

Cov_row9

Covariances of estimated parameters – lower left part of covariance matrix - row 9

 

9

CDF_DOUBLE

W_scale

Log (base 10) values of actual scaling of weigths of a-priori information

 

9

CDF_DOUBLE

ASMXAUX_1B Data Set Record, MDR_ASMAUX

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of VFM), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

dB_AOCS

Magnetic stray field vector of AOCS magneto-torquer coils, ASM frame

nT

3

CDF_DOUBLE

dB_Thrust

Magnetic stray field vector of AOCS thruster activations, ASM frame

nT

3

CDF_DOUBLE

dB_Battery

Magnetic stray field vector of battery currents, ASM frame

nT

3

CDF_DOUBLE

dB_SP

Magnetic stray field vector of solar panels currents, ASM frame

nT

3

CDF_DOUBLE

dB_Bus

Magnetic stray field vector of S/C bus currents, ASM frame

nT

3

CDF_DOUBLE

dB_VFM

Magnetic stray field vector of VFM sensor, ASM frame

nT

3

CDF_DOUBLE

dB_Static

Static magnetic stray field vector of S/C platform, ASM frame

nT

3

CDF_DOUBLE

dB_Ind

Magnetically induced stray field vector of S/C platform, ASM frame

nT

3

CDF_DOUBLE

dB_State

Instrument and sub-system state dependent magnetic stray field vector, ASM frame

nT

3

CDF_DOUBLE

VFMXAUX_1B Data Set Record, MDR_VFMAUX

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of VFM), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

dB_Sun

Magnetic field correction vector of Sun induced stray magnetic field, VFM frame (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

dB_AOCS

Magnetic stray field vector of AOCS magneto-torquer coils, VFM frame

nT

3

CDF_DOUBLE

dB_Thrust

Magnetic stray field vector of AOCS thruster activations, VFM frame

nT

3

CDF_DOUBLE

dB_Battery

Magnetic stray field vector of battery currents, VFM frame

nT

3

CDF_DOUBLE

dB_SP

Magnetic stray field vector of solar panels currents, VFM frame

nT

3

CDF_DOUBLE

dB_Bus

Magnetic stray field vector of S/C bus currents, VFM frame

nT

3

CDF_DOUBLE

dB_STR

Magnetic stray field vector of STR CHUs, VFM frame

nT

3

CDF_DOUBLE

dB_Static

Static magnetic stray field vector of S/C platform, VFM frame

nT

3

CDF_DOUBLE

dB_Ind

Magnetically induced stray field vector of S/C platform, VFM frame

nT

3

CDF_DOUBLE

dB_State

Instrument and sub-system state dependent magnetic stray field vector, VFM frame

nT

3

CDF_DOUBLE

MAGXMAN_1B Data Set Record, VFM_MAN_RP

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

delta_t

Time difference between first observation in the two ASM_VFM_IC records

s

1

CDF_DOUBLE

delta_bias

Differences in estimated offsets

nT

3

CDF_DOUBLE

delta_scale

Differences in estimated scale values

 

3

CDF_DOUBLE

delta_non orth

Differences in estimated non-orthogonality angles

mdeg

3

CDF_DOUBLE

Threshold1_bias

Threshold 1 value, bias

nT

1

CDF_DOUBLE

Threshold1_scale

Threshold 1 value, scale

 

1

CDF_DOUBLE

Threshold1_non-orth

Threshold 1 value, non-orthogonality

mdeg

1

CDF_DOUBLE

Threshold2_bias

Threshold 2 value, bias

nT

1

CDF_DOUBLE

Threshold2_scale

Threshold 2 value, scale

 

1

CDF_DOUBLE

Threshold2_non-orth

Threshold 2 value, non-orthogonality

mdeg

1

CDF_DOUBLE

Messages

Number of messages, the Message_ID field below is repeated Messages times

 

1

CDF_INT4

Message_ID

Message id, see Table 16 below

 

1

CDF_INT4

The values of Message_ID are given in the following table.

Value

Description

1

All changes within threshold1. CCDB remains unchanged.

10

All changes within threshold2, at least one change above threshold1. CCDB parameters to be updated with linear change in time.

100

At least on change above threshold2. Furhter investigations needed. CCDB remains unchanged until further notice.

TBD

Additional messages, warnings, and errors

Table 16: VFM_MAN_RP Message_ID Values

Plasma Data Set Record, MDR_EFI_PL

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of TII), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

Latitude

Position in ITRF – Geocentric latitude

deg

1

CDF_DOUBLE

Longitude

Position in ITRF – Geocentric longitude

deg

1

CDF_DOUBLE

Radius

Position in ITRF – Radius

m

1

CDF_DOUBLE

v_SC

Spacecraft velocity, NEC frame

m/s

3

CDF_DOUBLE

v_ion

Ion velocity, NEC frame

m/s

3

CDF_DOUBLE

v_ion_error

Error estimate of v_ion, NEC frame

m/s

3

CDF_DOUBLE

E

Electric field vector, NEC frame

mV/m

3

CDF_DOUBLE

E_error

Error estimate of E, NEC frame

mV/m

3

CDF_DOUBLE

dt_LP

Time offset of plasma density, t_n = t + dt_LP

s

1

CDF_DOUBLE

n

Plasma density (electron)

cm-3

1

CDF_DOUBLE

n_error

Error estimate of plasma density (n), a value of 2^32-1 = 4294967295 means undetermined

cm-3

1

CDF_DOUBLE

T_ion

Plasma ion temperature

K

1

CDF_DOUBLE

T_ion_error

Error estimate of plasma ion temperature (T_ion)

K

1

CDF_DOUBLE

T_elec

Plasma electron temperature

K

1

CDF_DOUBLE

T_elec_error

Error estimate of plasma electron temperature (T_elec)), a value of 2^32-1 = 4294967295 means undetermined

K

1

CDF_DOUBLE

U_SC

Spacecraft potential

V

1

CDF_DOUBLE

U_SC_error

Error estimate of spacecraft potential (U_SC), a value of 2^32-1 = 32767 means undetermined

V

1

CDF_DOUBLE

v_ion_H

Ion velocity, horizontal (H) sensor

m/s

2

CDF_DOUBLE

v_ion_H_error

Error estimate of v_ion_H

m/s

2

CDF_DOUBLE

v_ion_V

Ion velocity, vertical (V) sensor

m/s

2

CDF_DOUBLE

v_ion_V_error

Error estimate of v_ion_V

m/s

2

CDF_DOUBLE

rms_fit_H

RMS fit error from TII x-profile 2-Gaussian fits, H sensor

 

1

CDF_DOUBLE

rms_fit_V

RMS fit error from TII x-profile 2-Gaussian fits, V sensor

 

1

CDF_DOUBLE

var_x_H

Variance in 16 Hz x moment during a halfsecond interval, H sensor

 

1

CDF_DOUBLE

var_y_H

Variance in 16 Hz y moment during a halfsecond interval, H sensor

 

1

CDF_DOUBLE

var_x_V

Variance in 16 Hz x moment during a halfsecond interval, V sensor

 

1

CDF_DOUBLE

var_y_V

Variance in 16 Hz y moment during a halfsecond interval, V sensor

 

1

CDF_DOUBLE

dv_mtq_H

Velocity deflection due to magnetotorquer, H sensor

m/s

1

CDF_DOUBLE

dv_mtq_V

Velocity deflection due to magnetotorquer, V sensor

m/s

1

CDF_DOUBLE

SAA

South Atlantic Anomaly proximity indicator, range 0-5

 

1

CDF_UINT1

Flags_LP

Flags indicating the source/method of LP measurements (n, T_elec, U_SC), see Table 6‑4

 

1

CDF_UINT1

Flags_LP_n

Flags characterizing the plasma density measurement, see Table 17

 

1

CDF_UINT1

Flags_LP_T_elec

Flags characterizing the electron temperature measurement, see Table 17

 

1

CDF_UINT1

Flags_LP_U_SC

Flags characterizing the spacecraft potential measurement, see Table 17

 

1

CDF_UINT1

Flags_TII

Flags characterizing the TII measurement, see Table 17

 

1

CDF_UINT1

Flags_Platform

Flags characterizing the S/C platform information (AOCS thrusters, VFM and STR status), see Table 17

 

1

CDF_UINT2

Maneuver_Id

Current maneuver identification code

 

1

CDF_UINT2

The flags of the LP and TII measurements are defined in the following table:

Flag

Value

Description

Flags_LP

1

Probe 1, Harmonic Mode (p1hm – for this and the following acronyms see [AD-9])

2

Probe 2, Harmonic Mode (p2hm)

3

Probe 1 & 2 joint analysis, Harmonic Mode (p12hm)

5

Weighted probe 1 & 1+2 joined, Harmonic Mode (p1wp12hm)

6

Weighted probe 2 & 1+2 joined, Harmonic Mode (p2wp12hm)

9

Probe 1, Sweep Mode (p1sm)

Flags_LP_xxx

10

Nominal data, error estimate applies

20

Use with caution, errors may be undetermined or underestimated

30

Use with great caution, significant systematic errors may be present; variations may give some information but absolute values cannot be trusted

40

Not suitable for scientific use

The values above are combined (added) with the following values

0

Nominal data

5

Overflows in linear region before FPGA processing

6

Overflows in retarded region before FPGA processing

7

Low faceplate current and no bias/offset compensation has been done

Flags_TII

1

RMS fit error from TII x-profile exceeds 3σ threshold, H sensor

2

RMS fit error from TII x-profile exceeds 3σ threshold, V sensor

3

RMS fit error from TII x-profile exceeds 3σ threshold, both sensors

The values above are combined (added) with the following values

10

Nominal data, error estimate applies

20

Use with caution, errors may be underestimated

30

Use with great caution, significant systematic errors may be present; variations may give some information but absolute values cannot be trusted

40

Not suitable for scientific use

Flags_Platform

The following values are added for all conditions which hold

0

Nominal attitude (STR) and magnetic field (VFM) data

1

One or more of 4 nearest STR samples based on one CHU alone

2

Gap in 4 nearest STR samples

4

Gap in VFM samples used for calculation of E

8

AOCS thrusters activated

16

Attitude (STR) information not available

32

Magnetic field vector (VFM) not available

Table 17: Flags of the LP and TII Measurements

LP Offset Determination Data Set Records, LP__OFF_CA

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status, source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

Probe1_I_Bias_Offset

Probe 1 current bias offset

V

1

CDF_DOUBLE

Probe1_I_Slope_Offset

Probe 1 current slope offset

V

1

CDF_DOUBLE

Probe1_I_Fit_Error

Probe 1 current sweep fit error

V

1

CDF_DOUBLE

Probe1_U_Bias_Offset

Probe 1 voltage bias offset

V

1

CDF_DOUBLE

Probe1_U_Slope_Offset

Probe 1 voltage slope offset

V

1

CDF_DOUBLE

Probe1_U_Fit_Error

Probe 1 voltage sweep fit error

V

1

CDF_DOUBLE

Probe2_I_Bias_Offset

Probe 2 current bias offset

V

1

CDF_DOUBLE

Probe2_I_Slope_Offset''''

Probe 2 current slope offset

V

1

CDF_DOUBLE

Probe2_I_Fit_Error''''

Probe 2 current sweep fit error

V

1

CDF_DOUBLE

Probe2_U_Bias_Offset

Probe 2 voltage bias offset

V

1

CDF_DOUBLE

Probe2_U_Slope_Offset

Probe 2 voltage slope offset

V

1

CDF_DOUBLE

Probe2_U_Fit_Error

Probe 2 voltage sweep fit error

V

1

CDF_DOUBLE

FP_I_Bias_Offset

Face Plate current bias offset

V

1

CDF_DOUBLE

FP_I_Slope_Offset''''

Face Plate current slope offset

V

1

CDF_DOUBLE

FP_I_Fit_Error''''

Face Plate current sweep fit error

V

1

CDF_DOUBLE

FP_U_Bias_Offset

Face Plate voltage bias offset

V

1

CDF_DOUBLE

FP_U_Slope_Offset

Face Plate voltage slope offset

V

1

CDF_DOUBLE

FP_U_Fit_Error

Face Plate voltage sweep fit error

V

1

CDF_DOUBLE

FP_I_offset

Face Plate current offset measurements

eu

32

CDF_INT2

FP_U_offset

Face Plate bias offset measurements

eu

32

CDF_INT2

P1_I_offset

Probe 1 current offset measurements

eu

32

CDF_INT2

P1_U_offset

Probe 1 bias offset measurements

eu

32

CDF_INT2

P1_ref_ADC2

Probe 1 reference ADC2

eu

32

CDF_INT2

P1_ground

Probe 1 ground

eu

32

CDF_INT2

P2_I_offset

Probe 2 current offset measurements

eu

32

CDF_INT2

P2_U_offset

Probe 2 bias offset measurements

eu

32

CDF_INT2

P2_ref_ADC2

Probe 2 reference ADC2

eu

32

CDF_INT2

P2_ground

Probe 2 ground

eu

32

CDF_INT2

P1_Slope

Probe 1 slope offset, determined on-board

V

1

CDF_DOUBLE

P1_Bias

Probe 1 bias offset, determined on-board

V

1

CDF_DOUBLE

P1_Error

Probe 1 sweep fit error, determined on-board

V

1

CDF_DOUBLE

P2_Slope

Probe 2 slope offset, determined on-board

V

1

CDF_DOUBLE

P2_Bias

Probe 2 bias offset, determined on-board

V

1

CDF_DOUBLE

P2_Error

Probe 2 sweep fit error, determined on-board

V

1

CDF_DOUBLE

TII Circular Fit Data Set Records, TII_FIT_CA

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

x0

Estimate of the x position of the image center. Sensor order: H, V (applies to all below)

 

2

CDF_DOUBLE

y0

Estimate of the y position of the image center.

 

2

CDF_DOUBLE

phi0

Estimate of mean azimuthal position of data points.

deg

2

CDF_DOUBLE

r0

Radius of best-fit circle

 

2

CDF_DOUBLE

rms''''

Goodness of fit (rms error)

 

2

CDF_DOUBLE

Samples''''

Number of data points used in fit

 

2

CDF_UINT4

Success

Flag indicating whether fit succeeded or not, 1 = success

 

2

CDF_UINT2

r1

Average of r1

 

2

CDF_DOUBLE

r1_r1

Average of r1*r1

 

2

CDF_DOUBLE

r1_y2

Average of r1*y2

 

2

CDF_DOUBLE

U_SC

Average of U_SC {spacecraft potential}

V

2

CDF_DOUBLE

dVgf

Average of (Vg – Vf) {deflection minus faceplate voltage}

V

2

CDF_DOUBLE

Qram

Average of (v_SC – vcr)2 {ram-directed plasma flow velocity, squared}

m2/s2

2

CDF_UINT4

r1_samples

Number of samples used in averages

 

2

CDF_UINT4

Position and Velocity Data Set Records, MDR_NAVSP3 and MDR_MODSP3

These Data Set records forms ASCII files following the Extended Standard Product 3 Orbit Format (SP3-c), cf [RD-5]. These files may be compressed thereby reducing their size significantly. The "Number of Records" in the table in Product File refers to the number of observations in one SP3 file.

Attitude Data Set Record, MDR_SAT_AT

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of STR), source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

q

Quaternion, transformation: ITRF ← S/C

 

4

CDF_DOUBLE

Flags_q

Flags characterizing the attitude information, see Table 14

 

1

CDF_UINT1

Maneuver_Id

Current maneuver identification code

 

1

CDF_UINT1

RINEX Observation Data Set Record, MDR_GPS_RO

These Data Set records forms the RINEX observations files according to [RD-4]. The format is thouroughly described in this document, rinex300.pdf, in particular Section 2 and Appendix A.

RINEX Navigation Data Set Record, MDR_GPS_RN

These Data Set records deviate from the RINEX GPS navigation files defined in [RD-4]. The format is thouroughly described in this document, rinex300.pdf, in particular Section 2 and Appendix A.

Acceleration Data Set Record, MDR_ACC_PR

FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Time of observation

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status, source and quality, see Appendix D of [AD-13]

 

1

CDF_UINT2

a

Non-gravitational, linear acceleration, partly converted, S/C frame

m/s2

3

CDF_DOUBLE

a_ang

Angular acceleration, partly converted, S/C frame

rad/s2

3

CDF_DOUBLE

p

Position of proof mass within cavity

m

3

CDF_DOUBLE

p_ang

Angular position of proof mass within cavity

rad

3

CDF_DOUBLE

Temp

Temperatures of ACC

°C

6

CDF_DOUBLE

VpLTC1043

Positive voltage of LTC1043

V

1

CDF_DOUBLE

VnLTC1043

Negative voltage of LTC1043

V

1

CDF_DOUBLE

U_pol

Polarization voltage

V

1

CDF_DOUBLE

a_centr

Centrifugal acceleration, S/C frame

m/s2

3

CDF_DOUBLE

a_GG

Gravity gradient acceleration, S/C frame

m/s2

3

CDF_DOUBLE

a_Sun

Acceleration due to Solar radiation pressure, S/C frame

m/s2

3

CDF_DOUBLE

e_Sun

Direction to the Sun, unit vector, S/C frame

 

3

CDF_DOUBLE

m_SC

Actual mass of S/C

kg

1

CDF_DOUBLE

r_CoG

Center of Gravity, S/C frame

m

3

CDF_DOUBLE

A_head

Cross section area normal, front

m2

3

CDF_DOUBLE

A_down

Cross section area normal, down

m2

3

CDF_DOUBLE

A_left

Cross section area normal, left (-Y)

m2

3

CDF_DOUBLE

A_right

Cross section area normal, right (+Y)

m2

3

CDF_DOUBLE

K_Earth

Downward optical reflectivity normal

m2

3

CDF_DOUBLE

P_Gas

Pressure of gas tanks

Pa

2

CDF_DOUBLE

T_Gas

Temperature of gas tanks

°C

2

CDF_DOUBLE

Thru_Acc_On

Not used (set to zero)

s

1

CDF_DOUBLE

Flags_ACC

Flags characterizing the ACC, see Table 18

 

1

CDF_UINT2

Flags_Platform

Flags characterizing the S/C platform information, see Table 18

 

1

CDF_UINT2

Maneuver_Id

Current maneuver identification code

 

1

CDF_UINT1

[1] "Observation" refers to the linear acceleration measurement; the angular acceleration measurement is approximately 0.12 s before.

 

Flag

Value

Description

Flags_ACC

0

Accelerometer measurements nominal (no corrections applied)

1

a_Sun correction applied

4

a_GG correction applied

8

a_centr correction applied

16

UPol detected as outlier

32

Not used

64

Temperature detected as outlier

128

Proof mass angular position (pang) detected as outlier

256

Proof mass linear position (p) detected as outlier

512

Angular acceleration (aang) detected as outlier

1024

Linear acceleration (a) detected as outlier

5…2047

All combinations of the values above

Flags_Platform

0

Platform telemetry nominal

4

Heater switching

5,6

Combination (sum) of values 1 and 2 with 4

8

Level 1a.Bus.State telemetry missing

9,10

Combination (sum) of values 1 and 2 with 8

16

Thruster firing

17…26

Combination (sum) of values 1/2, 4/8 and 16

32

Level 1a.AOCS.Thru_HK telemetry missing

33…42

Combination (sum) of values 1/2, 4/8 and 32

Table 18: Acceleration Product Flags