Level 1b Product Definitions
Contents
1 Magnetic Products
2 Plasma Products
3 Position Products
4 Orbit Counters
5 Details on Level 1b Product Data Set Records

5.1 MagH Data Set Record, MDR_MAG_HR

5.2 MagL Data Set Record, MDR_MAG_LR

5.3 MagC Data Set Record, MDR_MAG_CA

4.4 TCF.VFM Parameter Data Set Record, ASM_VFM_IC

5.5 ASMXAUX_1B Data Set Record, MDR_ASMAUX

5.6 VFMXAUX_1B Data Set Record, MDR_VFMAUX

5.7 MAGXMAN_1B Data Set Record, VFM_MAN_RP

5.8 EFI LP Data Set Record, MDR_EFI_LP

5.9 EFI interpolated LP Data Set Records, MDR_EFILPI

5.10 LP Offset Determination Data Set Records, LP__OFF_CA

5.11 TII Circular Fit Data Set Records, TII_FIT_CA

5.11 Position and Velocity Data Set Records, MDR_NAVSP3 and MDR_MODSP3

5.13 Attitude Data Set Record, MDR_SAT_AT

5.14 RINEX Observation Data Set Record, MDR_GPS_RO

5.15 RINEX Navigation Data Set Record, MDR_GPS_RN

5.16 Acceleration Data Set Record, MDR_ACC_PR
The Level 1b products of the Swarm mission contains timeseries of qualityscreen, calibrated, and corrected measurements given in physical, SI units in geolocalized 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:
Example illustrating the filename of the Swarm A Level 1b lowrate 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 
340 
MAGX_LR_1B 
Magnetic data, low rate 
1 Hz 
daily 
CDF 
.cdf 
11 
MAGX_CA_lB 
Magnetic Calibration data 
1 Hz 
daily 
CDF 
.cdf 
11 
MAGXMAN_1B 
Magnetic Calibration Manoeuvre report 
On demand 
 
CDF 
.cdf 
10^{3} 
EFIX_LP_1B 
Plasma data 
2 Hz 
daily 
CDF 
.cdf 
5.6 
EFIXLPI_1B 
Interpolated Plasma data 
1 Hz 
daily 
CDF 
.cdf 
3.0 
LP_X_CA_1B 
Langmuir Probe offset calibration data 
6 h 
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 
Onboard GPSR navigational solution 
1 Hz 
daily 
ASCII 
.sp3 
13 
GPSX_RO_1B 
GPS RINEX Observation data 
0.1 / 1 Hz 
daily 
ASCII 
.rnx 
8.8 or 88 
GPSX_RN_1B 
GPS RINEX Navigation data 
2 h 
daily 
ASCII 
.rnx 
0.25 
ACCX_PR_1B 
Preprocessed ACC data 
1 Hz 
daily 
CDF 
.cdf 
6 
SC_XDYN_1B 
Auxiliary data for precise orbit determination and acceleration modelling 
1 Hz 
daily 
CDF 
.cdf 
3.7 
ASMXAUX_1B 
ASM auxiliary data 
50 Hz 
daily 
CDF 
.cdf 
20 
VFMXAUX_1B 
VFM auxiliary data 
50 Hz 
daily 
CDF 
.cdf 
40 
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 MagH 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 MagL 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 (NorthEastCentre) frame. See [AD7] for further details on these frames.
The magnetic Level 1b product named MAGX_CA_lB (MagC 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 onboard 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 coestimated calibration adjustment parameters, and the magnetic vector disturbance, denoted with dB_{Sun} and considered as a stray field vector, is then applied. The corrected data presents such additional parameter, dB_{Sun}. MAGx_CA_1B also contains the precalibrated (i.e. without any stray field correction applied) VFM magnetic data ("B_{pre}") 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 MagH Data Set Record, MDR_MAG_HR.
t 
Time, UTC 
r 
Position of VFM sensor, ITRF, spherical coordinates (r, θ, φ) 
B_{VFM} 
Magnetic field vector, VFM frame 
B_{NEC} 
Magnetic field vector, NEC frame.
Note: this is set to zero if no attitude information is available (Flags_{q} = 255)

dB_{Sun} 
Sun induced stray magnetic field correction vector subtracted from measurements, VFM frame (implemented from Product Baseline 04). 
dB_{AOCS} 
AOCS magnetotorquer stray magnetic field correction vector subtracted from measurements, VFM frame. 
dB_{other} 
Stray magnetic field correction vector of all other sources subtracted from measurements, VFM frame. 
B_{error} 
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 SWTNDTUGS016

q_{NEC←CRF} 
Rotation from NEC to Common Reference Frame (CRF) 
Att_{error} 
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 B_{NEC} is obtained by interpolation over longer arcs of S/C motion), etc.

Flags_{B} 
Flags related to the magnetic field vector measurement 
Flags_{q} 
Flags related to the attitude data 
Flags_{Platform} 
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 MagL Data Set Record, MDR_MAG_LR.
t 
Time, UTC 
r 
Position of VFM sensor, ITRF, spherical coordinates 
F 
Magnetic field intensity ("scalar magnetic field") 
dF_{AOCS} 
AOCS magnetotorquer stray magnetic field intensity subtracted from scalar measurements 
dF_{other} 
Stray magnetic field intensity of all other sources subtracted from scalar measurements 
F_{error} 
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 SWTNDTUGS016

B_{VFM} 
Magnetic field vector, VFM frame.
Note: this is set to zero if insufficient vector magnetometer measurements are available (Flags_{B }= 255)

B_{NEC} 
Magnetic field vector, NEC frame.
Note: this is set to zero if insufficient vector magnetometer or attitude measurements are available (Flags_{B}= 255 or Flags_{q }= 255)

dB_{Sun} 
Sun induced stray magnetic field correction vector subtracted from measurements, VFM frame (implemented from Product Baseline 04). 
dB_{AOCS} 
AOCS magnetotorquer stray magnetic field correction vector subtracted from vector measurements, VFM frame. 
dB_{other} 
Stray magnetic field correction vector of all other sources subtracted from vector measurements, VFM frame. 
B_{error} 
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 SWTNDTUGS016

Q_{NEC←CRF} 
Rotation from NEC to Common Reference Frame (CRF) 
Att_{error} 
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 B_{NEC} is obtained by interpolation over longer arcs of S/C motion), etc.

Flags_{F} 
Flags related to the magnetic field intensity measurement 
Flags_{B} 
Flags related to the magnetic field vector measurement 
Flags_{q} 
Flags related to the attitude data 
Flags_{Platform} 
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 MagC 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 
dF_{AOCS} 
Stray magnetic field intensity correction of AOCS magnetotorquers 
dF_{other} 
Stray magnetic field intensity correction of all other sources. 
F_{error} 
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 SWTNDTUGS016 observing that F_{error} = F^{(3)}_{err}

F_{VFM} 
Converted, corrected, ASMfiltered and interpolated magnetic field intensity from VFM – also corrected for ASM filter group delay 
dt_{VFM} 
Time offset, dt_{VFM} = t_{out,VFM}^{near} – t^{shifted}, where t_{out,VFM}^{near} is the timestamp of the VFM sample nearest t shifted according to the ASM filter group delay (t^{shifted} ≈ t ‑ 1.2 s) 
B 
Converted and corrected magnetic field vector from VFM at time t^{shifted}+dt_{VFM} 
dB_{Sun} 
Magnetic stray field vector of Sun induced stray field at VFM sensor at time t^{shifted}+dt_{VFM} (implemented from Product Baseline 04) 
dB_{AOCS} 
Magnetic stray field vector of AOCS magnetotorquer at VFM sensor at time t^{shifted}+dt_{VFM} 
dB_{other} 
Magnetic stray field vector of all other sources at VFM sensor at time t^{shifted}+dt_{VFM} 
B_{pre} 
Precalibrated VFM magnetic field vector, VFM frame at time t^{shifted}+dt_{VFM} (implemented from Product Baseline 04) 
EU_{VFM} 
Raw VFM measurement at time t^{shifted}+dt_{VFM} 
T_{CDC} 
Temperature of VFM CDC at time t^{shifted}+dt_{VFM} 
T_{CSC} 
Temperature of VFM CSC at time t^{shifted}+dt_{VFM} 
T_{EU} 
Temperature of VFM electronic unit at time t^{shifted}+dt_{VFM} 
alpha 
Solar inclination angle, rotation about y axis, S/C frame at time t^{shifted}+dt_{VFM} (implemented from Product Baseline 04) 
beta 
Solar inclination angle, angleto y axis, S/C frame at time t^{shifted}+dt_{VFM} (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 .
t_{range} 
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 nonorthogonality angles 
Samples 
Number of samples used to estimate the parameters 
Rms 
Weighted rms (rootmeansquare) value of obtained misfit between VFM and ASM measurements 
Cov 
Covariances of the estimated parameters 
W_{scale} 
Log10 values of actual weigths of apriori 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 nonorthogonality angles 
Threshold1_bias 
Threshold 1 value for biases 
Threshold1_scale' 
Threshold 1 value for scale values 
Threshold1_nonorth 
Threshold 1 value for nonorthogonality angles 
Threshold2_bias 
Threshold 2 value for biases 
Threshold2_scale 
Threshold 2 value for scale values 
Threshold2_nonorth 
Threshold 2 value for nonorthogonality 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 timeinstants 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 
dB_{AOCS} 
Magnetic stray field vector of AOCS magnetotorquer coils (including magnetically induced effects of this) 
dB_{Thrust} 
Magnetic stray field vector of AOCS thruster activation 
dB_{Battery} 
Magnetic stray field vector of batteries charge/discharge currents 
dB_{SP} 
Magnetic stray field vector of solar panel currents 
dB_{Bus} 
Magnetic stray field vector of S/C bus currents 
dB_{VFM} 
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 timeinstants 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 
dB_{Sun} 
Magnetic stray field vector of Sun induced stray field (implemented from Product Baseline 04) 
dB_{AOCS} 
Magnetic stray field vector of AOCS magnetotorquer coils (including magnetically induced effects of this) 
dB_{Thrust} 
Magnetic stray field vector of AOCS thruster activation 
dB_{Battery} 
Magnetic stray field vector of batteries charge/discharge currents 
dB_{SP} 
Magnetic stray field vector of solar panel currents 
dB_{Bus} 
Magnetic stray field vector of S/C bus currents 
dB_{STR} 
Static magnetic stray field vector of STR Camera Head Units (CHUs) 
dB_{Static} 
Static magnetic stray field vector of rest of S/C 
dB_{Ind} 
Magnetically induced stray field vector, from S/C 
dB_{State} 
Instrument and subsystem state dependent stray field vector, including latch valves 
Table 8: Measurement Data Set Record of VFMXAUX_1B Product
Plasma Products
EFIX_LP_1B Product
The EFIX_LP_1B Product contains plasma data from the Langimur Probe (LP) of the Electrical Field Instrument (EFI). The plasma product encompasses the plasma density and temperature. Data is provided at 2 Hz rate. The time instant 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_LP
t 
Time, UTC 
r 
Position, ITRF, spherical geometric coordinates 
U_{orbit} 
Magnitude of S/C velocity in the ITRF 
N_{e} 
Plasma density 
N_{e,}_{error} 
Error estimate of N_{e} 
T_{e} 
Plasma electron temperature 
T_{e,error} 
Error estimate of T_{elec} 
V_{s} 
S/C potential 
V_{s,error} 
Error estimate of V_{s} 
Flags_{LP} 
Common flags of the LP data 
Flags_{Ne} 
Flags of the plasma density, N_{e} 
Flags_{Te} 
Flags of the electron temperature, T_{e} 
Flags_{Vs} 
Flags of the S/C potential, V_{s} 
Table 9: Measurement Data Set Records of EFIX_PL_1B Product
EFIXLPI_1B Product
The EFIXLPI_1B Product contains the EFIX_LP_1B plasma data interpolated at full UTC seconds, the same as the low resolution magnetic data MAG_LR.
The measurement data set record of the plasma product is listed in Table 10 below. See also Plasma Data Set Record, MDR_EFILPI
t 
Time, UTC 
r 
Position, ITRF, spherical geometric coordinates 
U_{orbit} 
Magnitude of S/C velocity in the ITRF 
N_{e} 
Plasma density 
N_{e,}_{error} 
Error estimate of N_{e} 
T_{e} 
Plasma electron temperature 
T_{e,error} 
Error estimate of T_{elec} 
V_{s} 
S/C potential 
V_{s,error} 
Error estimate of V_{s} 
Flags_{LP} 
Common flags of the LP data 
Flags_{Ne} 
Flags of the plasma density, N_{e} 
Flags_{Te} 
Flags of the electron temperature, T_{e} 
Flags_{Vs} 
Flags of the S/C potential, V_{s} 
Table 10: 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 onboard 
P1_Bias 
Probe 1 bias offset, determined onboard 
P1_Error 
Probe 1 fit error, determined onboard 
P2_Slope 
Probe 2 slope offset, determined onboard 
P2_Bias 
Probe 2 bias offset, determined onboard 
P2_Error 
Probe 2 fit error, determined onboard 
Table 10: TCF.LP 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 onboard navigational solution as well as medium precision orbit information and S/C orientation: GPSXNAV_1B, MODX_SC_1B, and STRXATT_1B (Ephemeris Products)

Preprocessed nongravitional 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 [RD4]  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 onboard 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) 
Flags_{q} 
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 preprocessed 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 
Preprocessed linear acceleration data, S/C frame 
a_{ang} 
Preprocessed angular acceleration data, S/C frame 
p 
Position of proof mass within ACC cavity 
p_{ang} 
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) 
U_{pol} 
Polarization voltage 
a_{centr}* 
Centrifugal acceleration, S/C frame 
a_{GG}* 
Gravity gradient acceleration, S/C frame 
a_{Sun}* 
Acceleration due to Solar radiation pressure, S/C frame 
e_{Sun} 
Direction to the Sun, unit vector, S/C frame 
A_{Xxx} 
Cross sections of the S/C, orbit frame, Xxx = head, down, left, right 
K_{Earth} 
Downward optical reflectivity normal 
m_{S/C} 
Mass of S/C 
r_{CoG} 
Position of CoG, S/C frame 
P_{Gas} 
Pressure of gas tanks 
T_{Gas} 
Temperature of gas tanks 
Thru_Acc_On 
Accumulated thruster on time 
Flags_{ACC} 
Flags related to the ACC 
Flags_{Platform} 
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 Flags_{ACC}. 
Table 13: Measurement Data Set Record of ACCX_PR_1B Product
Spacecraft Dynamics Product
The SC_XDYN_1B Product contains auxiliary data needed for precise orbit determination and nongravitational force modelling.
The data set record of the SC_XDYN_1B Product is given in the table below.
t 
Time, UTC 
a_{Sun} 
Acceleration due to Solar radiation pressure, S/C frame 
e_{Sun} 
Direction to the Sun, unit vector, S/C frame 
A_{Xxx} 
Cross sections of the S/C, orbit frame, Xxx = head, down, left, right 
K_{Earth} 
Downward optical reflectivity normal 
m_{S/C} 
Mass of S/C 
r_{CoG} 
Position of CoG, S/C frame 
P_{Gas} 
Pressure of gas tanks 
T_{Gas} 
Temperature of gas tanks 
Flags_{Platform} 
Flags related to the S/C platform (indicates if all inputs were available or one or more was missing) 
dt_{thr} 
Thruster ontime in seconds (Start of ontime at "Timestamp"), field with 12 colmns (column 1 = ACT 1,… , column 9 = OCT 1,…) 
thr_{set} 
Flag indicating which thruster branch was active (= 0 for no thrusters powered, = 1 for main units powered, = 2 for redundant units powered, =3 for both main and redundant units powered) 
f_{thr} 
Nominal thrust force of activated thrusters (combined force), field with 3 columns 
Orbit Counters
This section contains the describtion of the L1b data product file containing the Swarm orbit numbers. The new Swarm Orbit Counter data file is referred with a new dedicated product type (ORBxCNT), and it provides precise Swarm orbit number information to the scientific user community.
AUXxORBCNT Product
Product identifier 
AUXxORBCNT 
Definition 
The Swarm orbit counter auxiliary data file provides precise Swarm orbit number information. The start of an orbit is defined as the Equator crossing of the ascending node (i.e. the northbound Equator crossing). For more information see product document. 
Units 
 
Quality indicator 
Source of orbit number information Values: best quality is 0 and reduced quality is 1. 
Data format 
ASCII
Field name 
Type 
Unit 
Contents 
orbit 
integer 
 
Orbit number 
MJD2000 
real 
MJD2000 
Orbit start date/time in MJD2000 
date 
string 
 
Orbit start date 
UT 
string 
UTC 
Orbit start time 
phi_AN 
real 
deg 
Longitude of orbit start 
Source 
integer 
 
Source of orbit number information Values:
Best quality = 0
Reduced quality = 1 

Update rate 
Daily 
Availability 
Swarm Data Access 
Notes 

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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 = nanoTesla (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


MagH 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 [AD13]


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 magnetotorquer 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

57

Combination (sum) of values 14

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

Onground aberrational correction of any attitude sample among 4 nearest STR samples.

914

As 17 above with onground 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 24 attitudes of CHU1 and CHU2 in 4 nearest STR samples, but not both simultaneously

20

Lack of 24 attitudes of CHU1 and CHU3 in 4 nearest STR samples, but not both simultaneously

21

Lack of 24 attitudes of CHU2 and CHU3 in 4 nearest STR samples, but not both simultaneously

22

Lack of 34 attitudes of CHU1, CHU2, and CHU3 in 4 nearest STR samples, but not two simultaneously

23

Not currently used

2430

As 1622 above with onground 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

3639

Not currently used

4043

As 3235 above with onground aberrational correction.

4447

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

5662

As 4854 above with onground aberrational correction.

63254

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

57

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

8

Outlier detected in Bus currents

915

Used for combinations (sum) of values 18

16

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

1731

Used for combinations (sum) of values 116

32

Change in instrument state according to Bus telemetry

3363

Used for combinations (sum) of values 132

64

No Bus telemetry available (for extended period)

6567

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

128

Gap in AOCS telemetry

129195

Used for combinations (sum) of values 167 and 128

256

Position information based on onboard (GPSR) navigational solution

257323 384451

Used for combinations (sum) of values 167, 128, and 256

Table 14: Flag Values of MDR_MAG_HR
MagL 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 [AD13]


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 magnetotorquer 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 magnetotorquer 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

57

Combination (sum) of values 14

8

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

915

Combination (sum) of values 18

16

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

1731

Combination (sum) of values 116

32

Gap in 4 nearest ASM samples

3363

Combination (sum) of values 132

64

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

6579 96111

Combination (sum) of value 64 with values 115 and 3247

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

57

Combination (sum) of values 14

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)

1724 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
MagC 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 [AD13]


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 magnetotorquer 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 t^{shifted}+dt

nT

3

CDF_DOUBLE

dB_Sun

Magnetic stray field correction vector of Sun induced stray field, VFM frame, time t^{shifted}+dt_VFM (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

dB_AOCS

Magnetic stray field correction vector of AOCS magnetotorquer coils, VFM frame, time t^{shifted}+dt_VFM

nT

3

CDF_DOUBLE

dB_other

Magnetic stray field correction vector of all other sources, VFM frame, time t^{shifted}+dt_VFM

nT

3

CDF_DOUBLE

B_pre

Precalibrated VFM magnetic field vector, VFM frame, time t^{shifted}+dt_VFM (implemented from Product Baseline 04)

nT

3

CDF_DOUBLE

EU_VFM

Raw VFM measuremet, time t^{shifted}+dt_VFM

eu

3

CDF_DOUBLE

T_CDC

Temperature of VFM CDC, time t^{shifted}+dt_VFM

°C

1

CDF_DOUBLE

T_CSC

Temperature of VFM CSC, time t^{shifted}+dt_VFM

°C

1

CDF_DOUBLE

T_EU

Temperature of VFM EU, time t^{shifted}+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 t^{shifted}+dt_VFM (implemented from Product Baseline 04)

deg

1

CDF_DOUBLE

beta

Solar inclination angle, angleto y axis, S/C frame, time t^{shifted}+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 nonorthogonalities

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 apriori 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 [AD13]


1

CDF_UINT2

dB_AOCS

Magnetic stray field vector of AOCS magnetotorquer 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 subsystem 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 [AD13]


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 magnetotorquer 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 subsystem 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 nonorthogonality 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_nonorth

Threshold 1 value, nonorthogonality

mdeg

1

CDF_DOUBLE

Threshold2_bias

Threshold 2 value, bias

nT

1

CDF_DOUBLE

Threshold2_scale

Threshold 2 value, scale


1

CDF_DOUBLE

Threshold2_nonorth

Threshold 2 value, nonorthogonality

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_LP
FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Timestamp of the LP measurement

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of LP), source and quality, see Appendix D of SWRSDSCSY0007


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

U_orbit

Magnitude of spacecraft velocity in the ITRF 
m/s 
1 
CDF_DOUBLE 
Ne

Plasma density (electron)

cm^{3}

1

CDF_DOUBLE

Ne_error

Error of the plasma density estimate

cm^{3}

1

CDF_DOUBLE

Te

Plasma electron temperature

K

1

CDF_DOUBLE

Te_error

Error of the electron temperature estimate

K

1

CDF_DOUBLE

Vs

Spacecraft potential

V

1

CDF_DOUBLE

Vs_error

Error of the spacecraft potential estimate

V

1

CDF_DOUBLE

Flags_LP

Flags indicating the source of measurements, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Ne

Flags characterizing the plasma density measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Te

Flags characterizing the electron temperature measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Vs

Flags characterizing the spacecraft potential measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Plasma Data Set Record, MDR_EFILPI
FIELD

DESCRIPTION

UNITS

DIM

TYPE

Timestamp

Exact UTC second of the interpolated LP measurement

UTC

1

CDF_EPOCH

SyncStatus

Time synchronization status (of LP), source and quality, see Appendix D of SWRSDSCSY0007


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

U_orbit

Magnitude of spacecraft velocity in the ITRF 
m/s 
1 
CDF_DOUBLE 
Ne

Plasma density (electron)

cm^{3}

1

CDF_DOUBLE

Ne_error

Error of the plasma density estimate

cm^{3}

1

CDF_DOUBLE

Te

Plasma electron temperature

K

1

CDF_DOUBLE

Te_error

Error of the electron temperature estimate

K

1

CDF_DOUBLE

Vs

Spacecraft potential

V

1

CDF_DOUBLE

Vs_error

Error of the spacecraft potential estimate

V

1

CDF_DOUBLE

Flags_LP

Flags indicating the source of measurements, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Ne

Flags characterizing the plasma density measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Te

Flags characterizing the electron temperature measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

Flags_Vs

Flags characterizing the spacecraft potential measurement, see Table 64 of SWRSDSCSY0007


1

CDF_UINT1

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 [AD13]


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 onboard

V

1

CDF_DOUBLE

P1_Bias

Probe 1 bias offset, determined onboard

V

1

CDF_DOUBLE

P1_Error

Probe 1 sweep fit error, determined onboard

V

1

CDF_DOUBLE

P2_Slope

Probe 2 slope offset, determined onboard

V

1

CDF_DOUBLE

P2_Bias

Probe 2 bias offset, determined onboard

V

1

CDF_DOUBLE

P2_Error

Probe 2 sweep fit error, determined onboard

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 bestfit 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 – v_{cr})^{2} {ramdirected plasma flow velocity, squared}

m^{2}/s^{2}

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 (SP3c), cf [RD5]. 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 [AD13]


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 [RD4]. 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 [RD4]. 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 [AD13]


1

CDF_UINT2

a

Nongravitational, linear acceleration, partly converted, S/C frame

m/s^{2}

3

CDF_DOUBLE

a_ang

Angular acceleration, partly converted, S/C frame

rad/s^{2}

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/s^{2}

3

CDF_DOUBLE

a_GG

Gravity gradient acceleration, S/C frame

m/s^{2}

3

CDF_DOUBLE

a_Sun

Acceleration due to Solar radiation pressure, S/C frame

m/s^{2}

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

m^{2}

3

CDF_DOUBLE

A_down

Cross section area normal, down

m^{2}

3

CDF_DOUBLE

A_left

Cross section area normal, left (Y)

m^{2}

3

CDF_DOUBLE

A_right

Cross section area normal, right (+Y)

m^{2}

3

CDF_DOUBLE

K_Earth

Downward optical reflectivity normal

m^{2}

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

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

U_{Pol} detected as outlier

32

Not used

64

Temperature detected as outlier

128

Proof mass angular position (p_{ang}) detected as outlier

256

Proof mass linear position (p) detected as outlier

512

Angular acceleration (a_{ang}) 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

Links
