HDF4 file: 368 data descriptors
library version = "NCSA HDF Version 4.1 Release 2, March 1998"
data description = (text block)
| The file 'mag_level2_data_4min.h' is shown below, it was used to create the data in the Vgroup named 'VG_MAG_data_4min'.
| 
| /* Id: mag_level2_data_4min.h,v 1.1 2000/08/02 00:48:18 asc Exp $ */
| 
| #include "hdfi.h"
| 
| struct MAG_data_4min {
| 
|   /* UT time at the start of the periods */
|   int32   year;                         /* integer year */
|   int32   day;                          /* integer day of year */
|   int32   hr;                           /* hour of day */
|   int32   min;                          /* min of hour */
|   float32 sec;                          /* seconds */
|   float64 fp_year;                      /* floating point year */
|   float64 fp_doy;                       /* floating point Day of YearDOY */
|   float64 ACEepoch;                     /* UT time in sec since 1/1/96 */
| 
|   /* ACE frame count */
|   uint32 SCclock;
| 
|   /* mag average data */
|   float32 Br;
|   float32 Bt;
|   float32 Bn;
| 
|   float32 Bmag;
|   float32 Delta;
|   float32 Lambda;
| 
|   float32 Bgse_x;
|   float32 Bgse_y;
|   float32 Bgse_z;
| 
|   float32 Bgsm_x;
|   float32 Bgsm_y;
|   float32 Bgsm_z;
| 
|   float32 dBrms;
| 
|   float32 sigma_B;
| 
|   float32 fraction_good;
|   int32   N_vectors;
| 
|   /* data quality for period; data types 1 and 2 have been excised */
|   int32  Quality;                      /* =0 Normal; */
|                                        /* =1 Maneuver & Relaxation*/
| 				       /* =2 Bad data */
| 
|   /* Sensor Position in gse coordinates */
|   float32 pos_gse_x;
|   float32 pos_gse_y;
|   float32 pos_gse_z;
| 
|   /* Sensor Position in gsm coordinates */
|   float32 pos_gsm_x;
|   float32 pos_gsm_y;
|   float32 pos_gsm_z;
| 
| };
file description = (text block)
| Created by the ACE Science Center (ASC) --
| ACE Science Center Level 2 Software Version:  1.4
| ACE Science Center Processing Date/Time: Wed Jul 31 13:08:40 PDT 2002
| For more info email us at: asc@srl.caltech.edu
| 
| 
| For each Bartels Rotation (27.000 day periods):
| 
| 	Type of File	Number of Records
| 	-------------   -----------------
| 	16 second	145,800
| 	4 minute	9720
| 	1 hour		648
| 	1 day		27
| 	1 Bartels	1
| 
| Data error is less than 0.1 nT (where nT is nano-Tesla).
| 
| The timing data indicates the start of the integration period in Universal
| Time (UT) and is:
| 
| 	year	-	int32 year
| 	day	-	int32 day of year
| 	hr	-	int32 hour of day
| 	min	-	int32 minute of hour
| 	sec	-	float32 seconds (accurate to millisec)
| 	fp_year -       float64 fractional year
| 	fp_doy	-	float64 fractional day of year
| 	ACEepoch-	float64 ACE epoch time in seconds since Jan 1, 1996
| 			at 0hr UT
|   and
| 	SCclock	-	uint32 spacecraft clock time
| 
| The averaged Mag data, which are all float32, are:
| 
| 	Br	- The r component of the magnetic field vector in the RTN
| 		  coordinate system in nT
| 	Bt	- The t component of the magnetic field vector in the RTN
| 		  coordinate system in nT
| 	Bn	- The n component of the magnetic field vector in the RTN
| 		  coordinate system in nT
| 	Bmag	- The <|B|> magnetic field magnitude in nT
| 	Delta	- The angle in degrees with 0 at Br/Bt plane + toward Bn
| 		  (-90 to +90 degrees), i.e. the RTN latitude
| 	Lambda  - The angle in degrees with 0 at Br and + toward Bt
| 		  (0 to 360 degrees), i.e. the RTN longitude
| 	Bgse_x	- The x component of the magnetic field vector in the GSE
| 		  coordinate system in nT
| 	Bgse_y	- The y component of the magnetic field vector in the GSE
| 		  coordinate system in nT
| 	Bgse_z	- The z component of the magnetic field vector in the GSE
| 		  coordinate system in nT
| 
| The averaging of 16 sec data to form the longer time period data (4min, 1hr,
| 1day, and Bartels rotation) is simply:
| 
| 	Average = Sum(Mag data)/(Number of samples)
| 
| for the good data during the period.
| 
| 
| Information about the Mag data, float32 except as noted:
| 
| 	dBrms	- RMS values of underlying high-resolution measurements in nT.
| 		  This is the rms variation of the vector over the time
| 		  interval, calculated as follows:
|                         1) calculate the average magnitude of each of the three
|                            components of the vector, over the time interval.
|                         2) for each component, average the square of the
|                            difference between the measurement and the average
|                         3) add the averages from the three components
|                         4) take the square-root of the result.
| 		  i.e.
| 
| 		       dBrms = sqrt(sum_i<(B_i-<B_i>)^2>)
| 
| 		  For the 16-second averages, dBrms is calculated using the
| 		  the highest resolution data (3 vectors/second, from one of
| 		  the two sensors). For the 4-minute and hourly averages, the
| 		  16-second averages are used as input to the calculations.
| 
| 	sigma_B	- The variance of |B| over the time interval, in nT.
| 
| 		  i.e. sigma_B = sqrt(<(|B|-<|B|>)^2>).
| 
| 		  If sigma_B/<|B|> is small, there was little variation
| 		  during the time period.
| 		  If sigma_B/<|B|> is large, there was much variation
| 		  during the time period.
| 
| 		  sigma_B is only calculated for the 4-minute and hourly
| 		  averages. It is calculated using the 16-second averages
| 		  as input.
| 
| 	fraction_good
| 	         - Fraction of the timing period for which there was data
|                    available.
| 
| 	N_vectors- (in int32) Number of 16 second vectors that were included
| 		    in the average for the time period.
| 
| The data quality for the period (int32); data of type 2 have been excised,
| i.e. replaced with fill data (-999.9):
| 
| 	Quality	= 0 Normal data
|                 = 1 Spacecraft Maneuver & subsequent high-nutation period (~4 hr)
| 		= 2 Bad data/missing data
| 
| For daily and Bartels rotation averages, only Bmag data is valid. For Br,
| Bt, Bn, Delta, Lambda, Bgse_x, Bgse_y, and Bgse_z, the fill value (-999.9) is
| output.  Individual vector components on timescales longer than 1 hour are
| considered to be potentially misleading and have questionable value at 1 AU.
| For this reason, they are not computed.  Values of <|B|> may be more useful,
| but the user is cautioned to examine the dBrms value for these intervals as
| large values of dBrms may indicate significant changes in the magnetic field
| during the averaging interval.
file description = (text block)
| MAG Instrument team contact:
| 		   Charles W. Smith
| 	Phone:     302-831-8114
| 	Org:       Bartol Research Institute at University of Delaware
| 	Email:     chuck@bartol.udel.edu
| 
| 
| 	MAG Principal Investigator:
| 		   Norman F. Ness
| 	Phone:     302-831-8111
| 	Org:       Bartol Research Institute at University of Delaware
| 	Email:     nfness@bartol.udel.edu
| 	Fax:	   (302) 831-1843
file description = (text block)
| ***Initial File Names and Maneuver Events***
| 
|  Level-1_source_file = ACE_MAG_1998-293_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-293.dat
| 
|   Begin_ACE_location_GSE =        0.1463E+07 -0.2391E+06 -0.4206E+05 km
|   End_ACE_location_GSE =          0.1459E+07 -0.2359E+06 -0.4695E+05 km
|   Begin_ACE_location_GSM =        0.1463E+07 -0.2315E+06  0.7302E+05 km
|   End_ACE_location_GSM =          0.1459E+07 -0.2322E+06  0.6248E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1416E+07 -0.3838E+06 -0.2123E+06 km
|   End_ACE_location_J2000GCI =    -0.1404E+07 -0.4057E+06 -0.2271E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.986  0.167 -0.030
|   End_ACE_attitude_direction_cosines_RTN =    -0.982  0.180 -0.053
|   Begin_ACE_attitude_direction_cosines_GSE =   0.986 -0.167 -0.016
|   End_ACE_attitude_direction_cosines_GSE =     0.983 -0.182 -0.037
|   Begin_ACE_attitude_direction_cosines_GSM =   0.986 -0.155  0.063
|   End_ACE_attitude_direction_cosines_GSM =     0.983 -0.180  0.047
| 
| 
|  Level-1_source_file = ACE_MAG_1998-294_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-294.dat
| 
|   Begin_ACE_location_GSE =        0.1459E+07 -0.2359E+06 -0.4695E+05 km
|   End_ACE_location_GSE =          0.1456E+07 -0.2324E+06 -0.5180E+05 km
|   Begin_ACE_location_GSM =        0.1459E+07 -0.2322E+06  0.6248E+05 km
|   End_ACE_location_GSM =          0.1456E+07 -0.2312E+06  0.5685E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1404E+07 -0.4057E+06 -0.2271E+06 km
|   End_ACE_location_J2000GCI =    -0.1391E+07 -0.4275E+06 -0.2418E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.982  0.180 -0.053
|   End_ACE_attitude_direction_cosines_RTN =    -0.979  0.197 -0.055
|   Begin_ACE_attitude_direction_cosines_GSE =   0.983 -0.182 -0.037
|   End_ACE_attitude_direction_cosines_GSE =     0.979 -0.200 -0.037
|   Begin_ACE_attitude_direction_cosines_GSM =   0.983 -0.180  0.047
|   End_ACE_attitude_direction_cosines_GSM =     0.979 -0.195  0.056
| 
| 
|  Level-1_source_file = ACE_MAG_1998-295_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-295.dat
| 
|   Begin_ACE_location_GSE =        0.1456E+07 -0.2324E+06 -0.5180E+05 km
|   End_ACE_location_GSE =          0.1453E+07 -0.2286E+06 -0.5660E+05 km
|   Begin_ACE_location_GSM =        0.1456E+07 -0.2312E+06  0.5685E+05 km
|   End_ACE_location_GSM =          0.1453E+07 -0.2301E+06  0.4957E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1391E+07 -0.4275E+06 -0.2418E+06 km
|   End_ACE_location_J2000GCI =    -0.1378E+07 -0.4492E+06 -0.2564E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.979  0.197 -0.055
|   End_ACE_attitude_direction_cosines_RTN =    -0.993  0.100 -0.062
|   Begin_ACE_attitude_direction_cosines_GSE =   0.979 -0.200 -0.037
|   End_ACE_attitude_direction_cosines_GSE =     0.993 -0.104 -0.053
|   Begin_ACE_attitude_direction_cosines_GSM =   0.979 -0.195  0.056
|   End_ACE_attitude_direction_cosines_GSM =     0.993 -0.116 -0.002
| 
|    Maneuver_count = 1
|     Maneuver_start = 295.574813
|     Maneuver_end = 295.581850
|     Frame counts: 36540004 -- 36540612
| 
|  Level-1_source_file = ACE_MAG_1998-296_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-296.dat
| 
|   Begin_ACE_location_GSE =        0.1453E+07 -0.2286E+06 -0.5660E+05 km
|   End_ACE_location_GSE =          0.1450E+07 -0.2247E+06 -0.6135E+05 km
|   Begin_ACE_location_GSM =        0.1453E+07 -0.2301E+06  0.4957E+05 km
|   End_ACE_location_GSM =          0.1450E+07 -0.2284E+06  0.4504E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1378E+07 -0.4492E+06 -0.2564E+06 km
|   End_ACE_location_J2000GCI =    -0.1364E+07 -0.4708E+06 -0.2710E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.993  0.100 -0.062
|   End_ACE_attitude_direction_cosines_RTN =    -0.990  0.124 -0.064
|   Begin_ACE_attitude_direction_cosines_GSE =   0.993 -0.104 -0.053
|   End_ACE_attitude_direction_cosines_GSE =     0.990 -0.128 -0.052
|   Begin_ACE_attitude_direction_cosines_GSM =   0.993 -0.116 -0.002
|   End_ACE_attitude_direction_cosines_GSM =     0.990 -0.138  0.011
| 
| 
|  Level-1_source_file = ACE_MAG_1998-297_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-297.dat
| 
|   Begin_ACE_location_GSE =        0.1450E+07 -0.2247E+06 -0.6135E+05 km
|   End_ACE_location_GSE =          0.1446E+07 -0.2205E+06 -0.6604E+05 km
|   Begin_ACE_location_GSM =        0.1450E+07 -0.2284E+06  0.4504E+05 km
|   End_ACE_location_GSM =          0.1446E+07 -0.2244E+06  0.5115E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1364E+07 -0.4708E+06 -0.2710E+06 km
|   End_ACE_location_J2000GCI =    -0.1349E+07 -0.4922E+06 -0.2854E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.990  0.124 -0.064
|   End_ACE_attitude_direction_cosines_RTN =    -0.988  0.139 -0.067
|   Begin_ACE_attitude_direction_cosines_GSE =   0.990 -0.128 -0.052
|   End_ACE_attitude_direction_cosines_GSE =     0.988 -0.143 -0.054
|   Begin_ACE_attitude_direction_cosines_GSM =   0.990 -0.138  0.011
|   End_ACE_attitude_direction_cosines_GSM =     0.988 -0.151  0.023
| 
| 
|  Level-1_source_file = ACE_MAG_1998-298_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-298.dat
| 
|   Begin_ACE_location_GSE =        0.1446E+07 -0.2205E+06 -0.6604E+05 km
|   End_ACE_location_GSE =          0.1442E+07 -0.2162E+06 -0.7066E+05 km
|   Begin_ACE_location_GSM =        0.1446E+07 -0.2244E+06  0.5115E+05 km
|   End_ACE_location_GSM =          0.1442E+07 -0.2241E+06  0.3637E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1349E+07 -0.4922E+06 -0.2854E+06 km
|   End_ACE_location_J2000GCI =    -0.1334E+07 -0.5134E+06 -0.2996E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.988  0.139 -0.067
|   End_ACE_attitude_direction_cosines_RTN =    -0.985  0.157 -0.064
|   Begin_ACE_attitude_direction_cosines_GSE =   0.988 -0.143 -0.054
|   End_ACE_attitude_direction_cosines_GSE =     0.986 -0.161 -0.049
|   Begin_ACE_attitude_direction_cosines_GSM =   0.988 -0.151  0.023
|   End_ACE_attitude_direction_cosines_GSM =     0.986 -0.166  0.030
| 
| 
|  Level-1_source_file = ACE_MAG_1998-299_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-299.dat
| 
|   Begin_ACE_location_GSE =        0.1442E+07 -0.2162E+06 -0.7066E+05 km
|   End_ACE_location_GSE =          0.1439E+07 -0.2117E+06 -0.7521E+05 km
|   Begin_ACE_location_GSM =        0.1442E+07 -0.2241E+06  0.3637E+05 km
|   End_ACE_location_GSM =          0.1439E+07 -0.2241E+06  0.1561E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1334E+07 -0.5134E+06 -0.2996E+06 km
|   End_ACE_location_J2000GCI =    -0.1318E+07 -0.5344E+06 -0.3136E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.985  0.157 -0.064
|   End_ACE_attitude_direction_cosines_RTN =    -0.983  0.168 -0.071
|   Begin_ACE_attitude_direction_cosines_GSE =   0.986 -0.161 -0.049
|   End_ACE_attitude_direction_cosines_GSE =     0.984 -0.172 -0.055
|   Begin_ACE_attitude_direction_cosines_GSM =   0.986 -0.166  0.030
|   End_ACE_attitude_direction_cosines_GSM =     0.984 -0.180  0.018
| 
| 
|  Level-1_source_file = ACE_MAG_1998-300_V3-1.HDF;1
|  Filename = ACE_MAG_LV2_RTN_16sec_1998-300.dat
| 
|   Begin_ACE_location_GSE =        0.1439E+07 -0.2117E+06 -0.7521E+05 km
|   End_ACE_location_GSE =          0.1435E+07 -0.2071E+06 -0.7967E+05 km
|   Begin_ACE_location_GSM =        0.1439E+07 -0.2241E+06  0.1560E+05 km
|   End_ACE_location_GSM =          0.1435E+07 -0.2218E+06  0.6850E+04 km
|   Begin_ACE_location_J2000GCI =  -0.1318E+07 -0.5344E+06 -0.3137E+06 km
|   End_ACE_location_J2000GCI =    -0.1301E+07 -0.5551E+06 -0.3275E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.983  0.168 -0.071
|   End_ACE_attitude_direction_cosines_RTN =    -0.993  0.086 -0.080
|   Begin_ACE_attitude_direction_cosines_GSE =   0.984 -0.172 -0.055
|   End_ACE_attitude_direction_cosines_GSE =     0.993 -0.092 -0.071
|   Begin_ACE_attitude_direction_cosines_GSM =   0.984 -0.180  0.018
|   End_ACE_attitude_direction_cosines_GSM =     0.993 -0.112 -0.030
| 
|    Maneuver_count = 1
|     Maneuver_start = 300.652396
|     Maneuver_end = 300.659063
|     Frame counts: 36978708 -- 36979284
| 
|  Level-1_source_file = ACE_MAG_1998-301_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-301.dat
| 
|   Begin_ACE_location_GSE =        0.1435E+07 -0.2071E+06 -0.7968E+05 km
|   End_ACE_location_GSE =          0.1432E+07 -0.2025E+06 -0.8405E+05 km
|   Begin_ACE_location_GSM =        0.1435E+07 -0.2218E+06  0.6852E+04 km
|   End_ACE_location_GSM =          0.1432E+07 -0.2187E+06  0.1488E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1301E+07 -0.5552E+06 -0.3275E+06 km
|   End_ACE_location_J2000GCI =    -0.1284E+07 -0.5757E+06 -0.3412E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.993  0.086 -0.080
|   End_ACE_attitude_direction_cosines_RTN =    -0.991  0.105 -0.082
|   Begin_ACE_attitude_direction_cosines_GSE =   0.993 -0.092 -0.071
|   End_ACE_attitude_direction_cosines_GSE =     0.991 -0.111 -0.071
|   Begin_ACE_attitude_direction_cosines_GSM =   0.993 -0.112 -0.030
|   End_ACE_attitude_direction_cosines_GSM =     0.991 -0.131 -0.014
| 
| 
|  Level-1_source_file = ACE_MAG_1998-302_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-302.dat
| 
|   Begin_ACE_location_GSE =        0.1432E+07 -0.2025E+06 -0.8405E+05 km
|   End_ACE_location_GSE =          0.1428E+07 -0.1978E+06 -0.8831E+05 km
|   Begin_ACE_location_GSM =        0.1432E+07 -0.2187E+06  0.1489E+05 km
|   End_ACE_location_GSM =          0.1428E+07 -0.2159E+06  0.1812E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1284E+07 -0.5757E+06 -0.3412E+06 km
|   End_ACE_location_J2000GCI =    -0.1267E+07 -0.5960E+06 -0.3547E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.991  0.105 -0.082
|   End_ACE_attitude_direction_cosines_RTN =    -0.989  0.119 -0.084
|   Begin_ACE_attitude_direction_cosines_GSE =   0.991 -0.111 -0.071
|   End_ACE_attitude_direction_cosines_GSE =     0.990 -0.125 -0.071
|   Begin_ACE_attitude_direction_cosines_GSM =   0.991 -0.131 -0.014
|   End_ACE_attitude_direction_cosines_GSM =     0.990 -0.144 -0.002
| 
| 
|  Level-1_source_file = ACE_MAG_1998-303_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-303.dat
| 
|   Begin_ACE_location_GSE =        0.1428E+07 -0.1978E+06 -0.8831E+05 km
|   End_ACE_location_GSE =          0.1425E+07 -0.1930E+06 -0.9246E+05 km
|   Begin_ACE_location_GSM =        0.1428E+07 -0.2159E+06  0.1812E+05 km
|   End_ACE_location_GSM =          0.1425E+07 -0.2130E+06 -0.3101E+04 km
|   Begin_ACE_location_J2000GCI =  -0.1267E+07 -0.5960E+06 -0.3547E+06 km
|   End_ACE_location_J2000GCI =    -0.1249E+07 -0.6162E+06 -0.3679E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.989  0.119 -0.084
|   End_ACE_attitude_direction_cosines_RTN =    -0.987  0.137 -0.087
|   Begin_ACE_attitude_direction_cosines_GSE =   0.990 -0.125 -0.071
|   End_ACE_attitude_direction_cosines_GSE =     0.987 -0.143 -0.072
|   Begin_ACE_attitude_direction_cosines_GSM =   0.990 -0.144 -0.002
|   End_ACE_attitude_direction_cosines_GSM =     0.987 -0.160 -0.006
| 
| 
|  Level-1_source_file = ACE_MAG_1998-304_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-304.dat
| 
|   Begin_ACE_location_GSE =        0.1425E+07 -0.1930E+06 -0.9246E+05 km
|   End_ACE_location_GSE =          0.1422E+07 -0.1882E+06 -0.9650E+05 km
|   Begin_ACE_location_GSM =        0.1425E+07 -0.2130E+06 -0.3108E+04 km
|   End_ACE_location_GSM =          0.1422E+07 -0.2089E+06 -0.3300E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1249E+07 -0.6162E+06 -0.3679E+06 km
|   End_ACE_location_J2000GCI =    -0.1231E+07 -0.6361E+06 -0.3810E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.987  0.137 -0.087
|   End_ACE_attitude_direction_cosines_RTN =    -0.984  0.153 -0.089
|   Begin_ACE_attitude_direction_cosines_GSE =   0.987 -0.143 -0.072
|   End_ACE_attitude_direction_cosines_GSE =     0.984 -0.160 -0.072
|   Begin_ACE_attitude_direction_cosines_GSM =   0.987 -0.160 -0.006
|   End_ACE_attitude_direction_cosines_GSM =     0.984 -0.175 -0.019
| 
| 
|  Level-1_source_file = ACE_MAG_1998-305_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-305.dat
| 
|   Begin_ACE_location_GSE =        0.1422E+07 -0.1882E+06 -0.9650E+05 km
|   End_ACE_location_GSE =          0.1419E+07 -0.1832E+06 -0.1004E+06 km
|   Begin_ACE_location_GSM =        0.1422E+07 -0.2089E+06 -0.3300E+05 km
|   End_ACE_location_GSM =          0.1419E+07 -0.2063E+06 -0.3004E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1231E+07 -0.6362E+06 -0.3810E+06 km
|   End_ACE_location_J2000GCI =    -0.1213E+07 -0.6560E+06 -0.3938E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.984  0.153 -0.089
|   End_ACE_attitude_direction_cosines_RTN =    -0.981  0.170 -0.091
|   Begin_ACE_attitude_direction_cosines_GSE =   0.984 -0.160 -0.072
|   End_ACE_attitude_direction_cosines_GSE =     0.982 -0.177 -0.072
|   Begin_ACE_attitude_direction_cosines_GSM =   0.984 -0.175 -0.019
|   End_ACE_attitude_direction_cosines_GSM =     0.982 -0.190 -0.006
| 
| 
|  Level-1_source_file = ACE_MAG_1998-306_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-306.dat
| 
|   Begin_ACE_location_GSE =        0.1419E+07 -0.1832E+06 -0.1004E+06 km
|   End_ACE_location_GSE =          0.1416E+07 -0.1781E+06 -0.1041E+06 km
|   Begin_ACE_location_GSM =        0.1419E+07 -0.2063E+06 -0.3004E+05 km
|   End_ACE_location_GSM =          0.1416E+07 -0.2034E+06 -0.3084E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1213E+07 -0.6560E+06 -0.3939E+06 km
|   End_ACE_location_J2000GCI =    -0.1194E+07 -0.6758E+06 -0.4065E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.981  0.170 -0.091
|   End_ACE_attitude_direction_cosines_RTN =    -0.994  0.061 -0.093
|   Begin_ACE_attitude_direction_cosines_GSE =   0.982 -0.177 -0.072
|   End_ACE_attitude_direction_cosines_GSE =     0.994 -0.070 -0.085
|   Begin_ACE_attitude_direction_cosines_GSM =   0.982 -0.190 -0.006
|   End_ACE_attitude_direction_cosines_GSM =     0.994 -0.096 -0.054
| 
|    Maneuver_count = 1
|     Maneuver_start = 306.574979
|     Maneuver_end = 306.592386
|     Frame counts: 37490420 -- 37491924
| 
|  Level-1_source_file = ACE_MAG_1998-307_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-307.dat
| 
|   Begin_ACE_location_GSE =        0.1416E+07 -0.1781E+06 -0.1041E+06 km
|   End_ACE_location_GSE =          0.1414E+07 -0.1729E+06 -0.1077E+06 km
|   Begin_ACE_location_GSM =        0.1416E+07 -0.2034E+06 -0.3084E+05 km
|   End_ACE_location_GSM =          0.1414E+07 -0.1982E+06 -0.4628E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1194E+07 -0.6758E+06 -0.4065E+06 km
|   End_ACE_location_J2000GCI =    -0.1175E+07 -0.6956E+06 -0.4190E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.994  0.061 -0.093
|   End_ACE_attitude_direction_cosines_RTN =    -0.992  0.078 -0.097
|   Begin_ACE_attitude_direction_cosines_GSE =   0.994 -0.070 -0.085
|   End_ACE_attitude_direction_cosines_GSE =     0.992 -0.087 -0.088
|   Begin_ACE_attitude_direction_cosines_GSM =   0.994 -0.096 -0.054
|   End_ACE_attitude_direction_cosines_GSM =     0.992 -0.110 -0.054
| 
| 
|  Level-1_source_file = ACE_MAG_1998-308_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-308.dat
| 
|   Begin_ACE_location_GSE =        0.1414E+07 -0.1729E+06 -0.1077E+06 km
|   End_ACE_location_GSE =          0.1412E+07 -0.1674E+06 -0.1111E+06 km
|   Begin_ACE_location_GSM =        0.1414E+07 -0.1982E+06 -0.4627E+05 km
|   End_ACE_location_GSM =          0.1412E+07 -0.1965E+06 -0.4145E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1175E+07 -0.6956E+06 -0.4190E+06 km
|   End_ACE_location_J2000GCI =    -0.1155E+07 -0.7154E+06 -0.4313E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.992  0.078 -0.097
|   End_ACE_attitude_direction_cosines_RTN =    -0.990  0.096 -0.101
|   Begin_ACE_attitude_direction_cosines_GSE =   0.992 -0.087 -0.088
|   End_ACE_attitude_direction_cosines_GSE =     0.990 -0.105 -0.090
|   Begin_ACE_attitude_direction_cosines_GSM =   0.992 -0.110 -0.054
|   End_ACE_attitude_direction_cosines_GSM =     0.990 -0.131 -0.045
| 
| 
|  Level-1_source_file = ACE_MAG_1998-309_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-309.dat
| 
|   Begin_ACE_location_GSE =        0.1412E+07 -0.1674E+06 -0.1111E+06 km
|   End_ACE_location_GSE =          0.1410E+07 -0.1617E+06 -0.1144E+06 km
|   Begin_ACE_location_GSM =        0.1412E+07 -0.1965E+06 -0.4145E+05 km
|   End_ACE_location_GSM =          0.1410E+07 -0.1904E+06 -0.5448E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1155E+07 -0.7154E+06 -0.4313E+06 km
|   End_ACE_location_J2000GCI =    -0.1136E+07 -0.7353E+06 -0.4435E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.990  0.096 -0.101
|   End_ACE_attitude_direction_cosines_RTN =    -0.988  0.112 -0.102
|   Begin_ACE_attitude_direction_cosines_GSE =   0.990 -0.105 -0.090
|   End_ACE_attitude_direction_cosines_GSE =     0.989 -0.121 -0.089
|   Begin_ACE_attitude_direction_cosines_GSM =   0.990 -0.131 -0.045
|   End_ACE_attitude_direction_cosines_GSM =     0.989 -0.144 -0.044
| 
| 
|  Level-1_source_file = ACE_MAG_1998-310_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-310.dat
| 
|   Begin_ACE_location_GSE =        0.1410E+07 -0.1617E+06 -0.1144E+06 km
|   End_ACE_location_GSE =          0.1408E+07 -0.1556E+06 -0.1175E+06 km
|   Begin_ACE_location_GSM =        0.1410E+07 -0.1904E+06 -0.5448E+05 km
|   End_ACE_location_GSM =          0.1408E+07 -0.1849E+06 -0.6173E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1136E+07 -0.7353E+06 -0.4435E+06 km
|   End_ACE_location_J2000GCI =    -0.1115E+07 -0.7552E+06 -0.4555E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.988  0.112 -0.102
|   End_ACE_attitude_direction_cosines_RTN =    -0.994  0.048 -0.102
|   Begin_ACE_attitude_direction_cosines_GSE =   0.989 -0.121 -0.089
|   End_ACE_attitude_direction_cosines_GSE =     0.994 -0.058 -0.096
|   Begin_ACE_attitude_direction_cosines_GSM =   0.989 -0.144 -0.044
|   End_ACE_attitude_direction_cosines_GSM =     0.994 -0.085 -0.072
| 
|    Maneuver_count = 1
|     Maneuver_start = 310.682197
|     Maneuver_end = 310.688123
|     Frame counts: 37845284 -- 37845796
| 
|  Level-1_source_file = ACE_MAG_1998-311_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-311.dat
| 
|   Begin_ACE_location_GSE =        0.1408E+07 -0.1556E+06 -0.1175E+06 km
|   End_ACE_location_GSE =          0.1407E+07 -0.1491E+06 -0.1203E+06 km
|   Begin_ACE_location_GSM =        0.1408E+07 -0.1849E+06 -0.6173E+05 km
|   End_ACE_location_GSM =          0.1407E+07 -0.1808E+06 -0.6270E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1115E+07 -0.7552E+06 -0.4555E+06 km
|   End_ACE_location_J2000GCI =    -0.1094E+07 -0.7753E+06 -0.4673E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.994  0.048 -0.102
|   End_ACE_attitude_direction_cosines_RTN =    -0.992  0.067 -0.105
|   Begin_ACE_attitude_direction_cosines_GSE =   0.994 -0.058 -0.096
|   End_ACE_attitude_direction_cosines_GSE =     0.992 -0.077 -0.097
|   Begin_ACE_attitude_direction_cosines_GSM =   0.994 -0.085 -0.072
|   End_ACE_attitude_direction_cosines_GSM =     0.992 -0.106 -0.065
| 
| 
|  Level-1_source_file = ACE_MAG_1998-312_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-312.dat
| 
|   Begin_ACE_location_GSE =        0.1407E+07 -0.1491E+06 -0.1203E+06 km
|   End_ACE_location_GSE =          0.1406E+07 -0.1423E+06 -0.1231E+06 km
|   Begin_ACE_location_GSM =        0.1407E+07 -0.1808E+06 -0.6271E+05 km
|   End_ACE_location_GSM =          0.1406E+07 -0.1728E+06 -0.7436E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1094E+07 -0.7753E+06 -0.4673E+06 km
|   End_ACE_location_J2000GCI =    -0.1073E+07 -0.7953E+06 -0.4790E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.992  0.067 -0.105
|   End_ACE_attitude_direction_cosines_RTN =    -0.990  0.085 -0.111
|   Begin_ACE_attitude_direction_cosines_GSE =   0.992 -0.077 -0.097
|   End_ACE_attitude_direction_cosines_GSE =     0.990 -0.096 -0.100
|   Begin_ACE_attitude_direction_cosines_GSM =   0.992 -0.106 -0.065
|   End_ACE_attitude_direction_cosines_GSM =     0.990 -0.121 -0.066
| 
| 
|  Level-1_source_file = ACE_MAG_1998-313_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-313.dat
| 
|   Begin_ACE_location_GSE =        0.1406E+07 -0.1423E+06 -0.1231E+06 km
|   End_ACE_location_GSE =          0.1406E+07 -0.1351E+06 -0.1256E+06 km
|   Begin_ACE_location_GSM =        0.1406E+07 -0.1728E+06 -0.7436E+05 km
|   End_ACE_location_GSM =          0.1406E+07 -0.1680E+06 -0.7531E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1073E+07 -0.7953E+06 -0.4790E+06 km
|   End_ACE_location_J2000GCI =    -0.1051E+07 -0.8154E+06 -0.4904E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.990  0.085 -0.111
|   End_ACE_attitude_direction_cosines_RTN =    -0.988  0.102 -0.112
|   Begin_ACE_attitude_direction_cosines_GSE =   0.990 -0.096 -0.100
|   End_ACE_attitude_direction_cosines_GSE =     0.989 -0.113 -0.099
|   Begin_ACE_attitude_direction_cosines_GSM =   0.990 -0.121 -0.066
|   End_ACE_attitude_direction_cosines_GSM =     0.989 -0.139 -0.058
| 
| 
|  Level-1_source_file = ACE_MAG_1998-314_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-314.dat
| 
|   Begin_ACE_location_GSE =        0.1406E+07 -0.1351E+06 -0.1256E+06 km
|   End_ACE_location_GSE =          0.1405E+07 -0.1275E+06 -0.1279E+06 km
|   Begin_ACE_location_GSM =        0.1406E+07 -0.1680E+06 -0.7531E+05 km
|   End_ACE_location_GSM =          0.1405E+07 -0.1582E+06 -0.8708E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1051E+07 -0.8154E+06 -0.4904E+06 km
|   End_ACE_location_J2000GCI =    -0.1028E+07 -0.8355E+06 -0.5017E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.988  0.102 -0.112
|   End_ACE_attitude_direction_cosines_RTN =    -0.986  0.118 -0.116
|   Begin_ACE_attitude_direction_cosines_GSE =   0.989 -0.113 -0.099
|   End_ACE_attitude_direction_cosines_GSE =     0.986 -0.130 -0.101
|   Begin_ACE_attitude_direction_cosines_GSM =   0.989 -0.139 -0.058
|   End_ACE_attitude_direction_cosines_GSM =     0.986 -0.153 -0.060
| 
| 
|  Level-1_source_file = ACE_MAG_1998-315_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-315.dat
| 
|   Begin_ACE_location_GSE =        0.1405E+07 -0.1275E+06 -0.1279E+06 km
|   End_ACE_location_GSE =          0.1404E+07 -0.1195E+06 -0.1301E+06 km
|   Begin_ACE_location_GSM =        0.1405E+07 -0.1582E+06 -0.8708E+05 km
|   End_ACE_location_GSM =          0.1404E+07 -0.1504E+06 -0.9266E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1028E+07 -0.8355E+06 -0.5017E+06 km
|   End_ACE_location_J2000GCI =    -0.1004E+07 -0.8554E+06 -0.5127E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.986  0.118 -0.116
|   End_ACE_attitude_direction_cosines_RTN =    -0.994  0.020 -0.109
|   Begin_ACE_attitude_direction_cosines_GSE =   0.986 -0.130 -0.101
|   End_ACE_attitude_direction_cosines_GSE =     0.994 -0.031 -0.105
|   Begin_ACE_attitude_direction_cosines_GSM =   0.986 -0.153 -0.060
|   End_ACE_attitude_direction_cosines_GSM =     0.994 -0.058 -0.092
| 
|    Maneuver_count = 1
|     Maneuver_start = 315.661635
|     Maneuver_end = 315.710154
|     Frame counts: 38275508 -- 38279700
| 
|  Level-1_source_file = ACE_MAG_1998-316_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-316.dat
| 
|   Begin_ACE_location_GSE =        0.1404E+07 -0.1195E+06 -0.1301E+06 km
|   End_ACE_location_GSE =          0.1404E+07 -0.1112E+06 -0.1321E+06 km
|   Begin_ACE_location_GSM =        0.1404E+07 -0.1504E+06 -0.9266E+05 km
|   End_ACE_location_GSM =          0.1404E+07 -0.1488E+06 -0.8764E+05 km
|   Begin_ACE_location_J2000GCI =  -0.1004E+07 -0.8554E+06 -0.5127E+06 km
|   End_ACE_location_J2000GCI =    -0.9801E+06 -0.8751E+06 -0.5234E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.994  0.020 -0.109
|   End_ACE_attitude_direction_cosines_RTN =    -0.994  0.036 -0.107
|   Begin_ACE_attitude_direction_cosines_GSE =   0.994 -0.031 -0.105
|   End_ACE_attitude_direction_cosines_GSE =     0.994 -0.048 -0.101
|   Begin_ACE_attitude_direction_cosines_GSM =   0.994 -0.058 -0.092
|   End_ACE_attitude_direction_cosines_GSM =     0.994 -0.078 -0.080
| 
| 
|  Level-1_source_file = ACE_MAG_1998-317_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-317.dat
| 
|   Begin_ACE_location_GSE =        0.1404E+07 -0.1112E+06 -0.1321E+06 km
|   End_ACE_location_GSE =          0.1403E+07 -0.1025E+06 -0.1339E+06 km
|   Begin_ACE_location_GSM =        0.1404E+07 -0.1488E+06 -0.8764E+05 km
|   End_ACE_location_GSM =          0.1403E+07 -0.1446E+06 -0.8670E+05 km
|   Begin_ACE_location_J2000GCI =  -0.9801E+06 -0.8751E+06 -0.5234E+06 km
|   End_ACE_location_J2000GCI =    -0.9551E+06 -0.8946E+06 -0.5338E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.994  0.036 -0.107
|   End_ACE_attitude_direction_cosines_RTN =    -0.992  0.053 -0.110
|   Begin_ACE_attitude_direction_cosines_GSE =   0.994 -0.048 -0.101
|   End_ACE_attitude_direction_cosines_GSE =     0.993 -0.065 -0.103
|   Begin_ACE_attitude_direction_cosines_GSM =   0.994 -0.078 -0.080
|   End_ACE_attitude_direction_cosines_GSM =     0.993 -0.098 -0.071
| 
| 
|  Level-1_source_file = ACE_MAG_1998-318_V2-8.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-318.dat
| 
|   Begin_ACE_location_GSE =        0.1403E+07 -0.1025E+06 -0.1339E+06 km
|   End_ACE_location_GSE =          0.1403E+07 -0.9349E+05 -0.1355E+06 km
|   Begin_ACE_location_GSM =        0.1403E+07 -0.1446E+06 -0.8670E+05 km
|   End_ACE_location_GSM =          0.1403E+07 -0.1418E+06 -0.8367E+05 km
|   Begin_ACE_location_J2000GCI =  -0.9551E+06 -0.8946E+06 -0.5338E+06 km
|   End_ACE_location_J2000GCI =    -0.9293E+06 -0.9139E+06 -0.5439E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.992  0.053 -0.110
|   End_ACE_attitude_direction_cosines_RTN =    -0.991  0.067 -0.112
|   Begin_ACE_attitude_direction_cosines_GSE =   0.993 -0.065 -0.103
|   End_ACE_attitude_direction_cosines_GSE =     0.992 -0.079 -0.103
|   Begin_ACE_attitude_direction_cosines_GSM =   0.993 -0.098 -0.071
|   End_ACE_attitude_direction_cosines_GSM =     0.992 -0.115 -0.060
| 
| 
|  Level-1_source_file = ACE_MAG_1998-319_V2-9.HDF;1
|  Filename = ACE_MAG_LV2_16sec_1998-319.dat
| 
|   Begin_ACE_location_GSE =        0.1403E+07 -0.9349E+05 -0.1355E+06 km
|   End_ACE_location_GSE =          0.1402E+07 -0.8575E+05 -0.1368E+06 km
|   Begin_ACE_location_GSM =        0.1403E+07 -0.1418E+06 -0.8367E+05 km
|   End_ACE_location_GSM =          0.1402E+07 -0.1328E+06 -0.9147E+05 km
|   Begin_ACE_location_J2000GCI =  -0.9293E+06 -0.9139E+06 -0.5439E+06 km
|   End_ACE_location_J2000GCI =    -0.9071E+06 -0.9297E+06 -0.5522E+06 km
|   Begin_ACE_attitude_direction_cosines_RTN =  -0.991  0.067 -0.112
|   End_ACE_attitude_direction_cosines_RTN =    -0.990  0.084 -0.113
|   Begin_ACE_attitude_direction_cosines_GSE =   0.992 -0.079 -0.103
|   End_ACE_attitude_direction_cosines_GSE =     0.990 -0.097 -0.102
|   Begin_ACE_attitude_direction_cosines_GSM =   0.992 -0.115 -0.060
|   End_ACE_attitude_direction_cosines_GSM =     0.990 -0.129 -0.056
file description = (text block)
| ACE/MAG Release Notes:
| 
| The following are cummulative release notes for the ACE Magnetic Field
| Instrument (MAG) Level-2 datasets.  As new datasets are released or
| old datasets are processed, this file will be updated.
| 
| -------------------------------------------------------------------
| 
| August 10, 1998:
| 
| Release of DOY 1 -- 120 of 1998, Version 1 of MAG Level-2 data
| in RTN coordinates.  Each data file contains documentation of
| maneuver times, field components in RTN, |B|, latitude and longitude,
| and RMS values of underlying high-resolution measurements.
| 
| Data are 16-second averages of the vector measurements.  The datafiles
| are processed based on daily files of Level-1 data.  Bad or missing
| data is filled with -999.9, except at beginning or end of day when
| data is not supplied.  Time tags are approximate and good to better
| than 16 seconds.  ACE frame counts are exact and mark the beginning of
| the data averaging interval.
| 
| Use of single initial zeroes file for all of 120 day interval.  Results
| good to 1/3 nT.
| 
| Final alignment of sensors not yet performed, but correction expected
| to be smaller than above.
| 
| Release of daily graphics files included at same time.
| 
| Release of revised Level-2 data anticipated shortly.
| -------------------------------------------------------------------
| 
| March 5, 1999
| 
| Release of DOY 121 -- 300 of 1998, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Formats for data files are the same as before, except that headers
| are extended to include maneuver times, spacecraft location at
| beginning and end of the interval, and spacecraft attitude at same
| times.
| 
| Release of daily graphics files included at same time.  Graphics
| revised to include above additional header material.
| 
| Two days (DOY 263 and DOY 278) remain suspect with possibly analysis
| issues for Range-0 (low |B|) data.  Further analysis of these days
| is ongoing.
| 
| A revision of 1998 (Version 2) will be filed at a later date.
| --------------------------------------------------------------------
| 
| August 10, 1999
| 
| Release of DOY 301 -- 365 of 1998, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Formats for data files are unchanged.
| 
| Release of daily graphics files included at same time.
| --------------------------------------------------------------------
| 
| August 12, 1999
| 
| Release of DOY 1 -- 30 of 1999, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Release of daily graphics files at same time.
| 
| Data and plot formats are unchanged.
| ---------------------------------------------------------------------
| 
| September 29, 1999
| 
| Release of DOY 31 -- 109 of 1999, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| October 18, 1999
| 
| Release of DOY 152 -- 265 of 1999, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Release of this data interval is out of sequence with previous
| release in order for ACE to support Cassini flyby of Earth.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| October 21, 1999
| 
| Release of DOY 110 -- 151 of 1999, Version 1 of MAG Level-2 data
| in RTN coordinates.
| 
| Release of this data interval brings MAG release to DOY 265 of 1999.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| December 10, 1999
| 
| Two problems (one real and one potential) have come to the attention
| of the ACE/MAG team and must be acknowledged for the sake of those
| using MAG data.
| 
|   1)  Although the ground processing software (Level-2, Browse, and
|       RTSW codes) was designed to use -999.9 as badpoint values so
|       that "0" values should never appear in the dataset, it is now
|       known that Level-2 data does possess some frames with these
|       values.  They appear in 1/2 major frame subsets and the source
|       is not yet known.
| 
|   2)  The sunpulse anomaly of June 1999 may result in minor errors in
|       the spin period, which can result in spin tones and errors in
|       despun coordinate systems (RTN, GSE, etc.).  If so, the errors
|       will be small.  The dates and times for when this anomaly may
|       influence the data are from 13:50 June 5 until 16:00 June 12.
| ---------------------------------------------------------------------
| 
| March 1, 2000
| 
| Release of DOY 266 of 1999 -- DOY 57 of 2000, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of this data interval brings MAG release to DOY 057 of 2000.
| 
| Release of daily graphics files at same time.
| 
| Source of |B|=0 values not yet determined, but such values should be
| searched for in any analysis and the points treated as bad values.
| ---------------------------------------------------------------------
| 
| June 23, 2000
| 
| Release of DOY 58 of 2000 -- DOY 169 of 2000, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| October 13, 2000
| 
| Release of DOY 170 of 2000 -- DOY 271 of 2000, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Apparently unphysical RMS signatures during maneuver of DOY 230 that do
| not show up as shifts in mean field.  Source not known at present.
| 
| There continue to be intervals (generally short lasting a few hours to
| a day) when the apparent zero level of the combined spacecraft +
| instrument signal abruptly changes by < 0.5 nT (usually).  Since the
| shift sometimes occurs primarily along the spin axis of the spacecraft,
| we are not confident that we always resolve these events and the user
| should remain aware that at present such events may remain unresolved.
| The source(s) of these events is under investigation.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| April 5, 2001
| 
| Release of DOY 272 of 2000 -- DOY 353 of 2000, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| The source(s) of spacecraft field remain unresolved.  Zeroes are quite
| good for all three instrument ranges of interest at L1.  No strikingly
| anomalous signals are seen in this time, but continued analysis in
| scientific efforts may always reveal previously unknown problems.
| B=(0,0,0) values in processed data appear to persist, but source has
| never been identified and they must be treated as bad data.
| 
| Release of daily graphics files at same time.
| ---------------------------------------------------------------------
| 
| April 6, 2001
| 
| Release of DOY 354 of 2000 -- DOY 040 of 2001, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| ---------------------------------------------------------------------
| 
| May 18, 2001
| 
| Release of DOY 41 of 2001 -- DOY 120 of 2001, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| ---------------------------------------------------------------------
| 
| January 4, 2002
| 
| Release of DOY 121 of 2001 -- DOY 166 of 2001, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| ---------------------------------------------------------------------
| 
| January 7, 2002
| 
| Release of DOY 167 of 2001 -- DOY 365 of 2001, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| 
| Odd behavior during maneuver on DOY 205 (July 24, 2001).  RMS levels
| change by ~0.5 nT in step fashion several times although instrument
| range does not change.  Probably unresolved spacecraft signal, but
| data is not guaranteed during maneuvers.
| 
| ACE Science Center informs us that:
| 
| 	Larger than usual number of missing minor frames in telemetry for
| 	DOYs 351 (~0.6%) and 352 (~4%).  This does not interfere with
| 	processing or overall data quality of MAG data.
| 
| 	Attitude data for DOYs 356-360, inclusive, inaccurate to ~1 degree
| 	due to errors in the star scanner.
| ---------------------------------------------------------------------
| 
| July 16, 2002
| 
| Release of DOY 248 of 1997 -- DOY 365 of 1997, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| 
| MAG was only instrument on and taking data at this time, so there has
| been little call for the 1997 data.
| 
| Days 342-347 and 349 are missing due to halo insertion maneuver.  There
| was no science telemetry at this time.
| 
| The first 11 days of flight are difficult to analyze due to many reasons.
| However, at least some fraction of these will be released shortly following
| further analysis.
| 
| Several days show anomalous behavior:
| 
| 	Days 250-253 show odd 30-minute oscillation similar to that seen
| 	during first 11 days of mission.
| 
| 	Odd stepping in fluctuation level on days 258, 262, 266, 267, and
| 	353.
| 
| 	Zeroes appear to step briefly on days 276-277, 289, 302-304,
| 	316-317, and 332-333.
| 
| 	Both of the above effects are at the < 0.5 nT level.
| 
| 	Sources of the above behavior have not been identified, but
| 	further effort to refine the data will probably reduce or eliminate
| 	the effect.
| ---------------------------------------------------------------------
| 
| July 17, 2002
| 
| Release of DOY 245 of 1997 -- DOY 247 of 1997, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| 
| ACE was launched on DOY 237 of 1997.  Data from launch through DOY 244
| shows more rapidly changing zeroes of undetermined origin than is seen in
| the remainder of the mission to date.  A future version of the MAG
| processing software will better handle this situation.  Since this data
| is not now up to the standards of the ACE/MAG instrument team, we are not
| releasing these 8 days of data to the general public at this time.
| 
| If data from these 8 days are desired, please contact the ACE/MAG team and
| arrangements can be made to deliver the data in the best form available
| and at the same time that the appropriate warnings regarding data quality
| during this time can be provided.
| ---------------------------------------------------------------------
| 
| July 29, 2002
| 
| Rerelease of DOY 001 of 1998 -- DOY 300 of 1998, Version 1 of MAG Level-2
| data in RTN coordinates.
| 
| Release of daily plots in RTN coordinates at same time.
| 
| This release was motivated by an ASC request to standardize MAG data
| deposits in a form opiginally established with 1998-301 data.  This
| format contains the complete spacecraft position information that has
| been standard ever since.
| 
| The data released now should be identical to that which was released
| earlier, but in fact there are small differences.  Early in 1998 the
| data time tag used by the MAG team was approximate.  It is now correct.
| Also, small changes in the computed IMF have resulted from changes in
| the analysis program.  Generally, the changes are small.  The largest
| changes are seen on days 121 through 160 when changes up to 0.15 nT
| are seen.  Generally, but not always, the change results from better
| zeroes and contains a smaller spin tone.
| 
| A formal release of Version 2 data is still intended that will contain
| additional changes to the processing, but for now no version number
| other than 1 is attached to this data.
| 
| --- CWS
data description = (text block)
| The file 'level2_record_doy.h' is shown below, it was used to create the data in the Vgroup named 'VG_level2_record_doy'.
| 
| /* Id: level2_record_doy.h,v 1.1 2000/08/02 00:47:11 asc Exp $ */
| 
| #include "hdfi.h"
| 
| /* record year/DOY association */
| struct level2_record_doy {
| 
|   int32   record_number;             /* record number */
|   int32   year;                      /* integer year */
|   int32   day;                       /* integer day of year */
|   int32   days_jan_1_1996;           /* days since January 1, 1996 UT 0 hr*/
| 
| };
vgroup "VG_MAG_data_4min" class "VG_MAG_LEVEL2_DATA_4MIN"
	vdata "MAG_data_4min" class "ACE MAG level2_data_4min": fields year, day, hr, min, sec, fp_year, fp_doy, ACEepoch, SCclock, Br, Bt, Bn, Bmag, Delta, Lambda, Bgse_x, Bgse_y, Bgse_z, Bgsm_x, Bgsm_y, Bgsm_z, dBrms, sigma_B, fraction_good, N_vectors, Quality, pos_gse_x, pos_gse_y, pos_gse_z, pos_gsm_x, pos_gsm_y, pos_gsm_z; 9720 records
vgroup "VG_level2_record_doy" class "VG_LEVEL2_RECORD_DOY"
	vdata "level2_record_doy" class "level2_record DOY table": fields record_number, year, day, days_jan_1_1996; 27 records