PDS_VERSION_ID        = PDS3                                                  
RECORD_TYPE           = FIXED_LENGTH                                          
RECORD_BYTES          = 80                                                    
DATA_SET_ID           =  "MEX-M-MRS-1/2/3-EXT2-3400-V1.0"
PRODUCT_ID            = "TRK-2-21"                                            
PRODUCT_CREATION_TIME =  2013-05-17T10:33:38.000
                                                  
OBJECT                = TEXT                                                  
  PUBLICATION_DATE      = 1997-08-04                                          
  NOTE                    = "Software Interface Specification for the JPL     
                             DSN TSAC Universal Time and Polar Motion (UTPM)  
                             file and the TEMPO Earth Orientation Parameters  
                             (EOP) file.  Adapted from the HTML file at URL   
                             http://epic.jpl.nasa.gov/nav/eop/trk-2-21.html   
                             Formatted for display or printing at 58 lines    
                             per page with up to 78 constant width            
                             characters per line."                            
END_OBJECT            = TEXT                                                  
END                                                                           
                                                                              
                                                                              
TRK-2-21 EOP Data Interface                                                   
DSN SYSTEMS REQUIREMENTS                                                      
DETAILED INTERFACE DESIGN                                                     
                                                                              
DOCUMENT 820-13; Rev. A                                                       
TRK-2-21                                                                      
                                                                              
DSN TRACKING SYSTEM INTERFACES                                                
EARTH-ORIENTATION PARAMETER DATA INTERFACE                                    
                                                                              
CONTENTS                                                                      
                                                                              
  PURPOSE                                                                     
  REVISION AND CONTROL                                                        
  GENERAL INFORMATION                                                         
  UTPM STOIC DATA FORMAT                                                      
   STOIC data file with seconds past 2000 time tags                           
   STOIC data file with seconds past 1950 time tags                           
  EOP DATA FORMAT                                                             
  Sample EOP file                                                             
  GLOSSARY                                                                    
                                                                              
                                                                              
PURPOSE                                                                       
                                                                              
This module defines the data format and content of the Earth-Orientation      
Parameter (EOP) files and the Universal Time and Polar Motion (UTPM) files    
received from the Tracking System Analytic Calibration (TSAC) group.(NOTE:    
These files are now produced by the Time and Earth Motion Precision           
Observation (TEMPO) group.)                                                   
                                                                              
                                                                              
REVISION AND CONTROL                                                          
                                                                              
Revisions or changes to the information herein presented may be initiated in  
accordance with the procedures in Section I of this document.                 
                                                                              
GENERAL INFORMATION                                                           
                                                                              
The DSN and flight projects use EOP data, which includes UTPM data, in the    
process of performing orbit determination and generating prediction data.     
These data are to be provided at intervals determined by the user's accuracy  
requirements and as negotiated with the various DSN and project users.        
                                                                              
Two different file formats are described in this interface document. The first
kind of file contains Universal Time and Polar Motion (UTPM) data only, and   
has the same format as was described in the previous version of TRK-2-21.  It 
will be referred to hereafter as the UTPM STOIC file; in the past, such files 
have also been called TPOLY files or TP arrays. The second kind of file       
contains UTPM data and, in addition, nutation correction parameters necessary 
to determine inertial station locations at the few-cm level. It will be       
referred to as the EOP file. For a detailed explanation of the models         
underlying this file, and how the file is used, see Folkner et al., "Earth    
Orientation Parameter (EOP) file description and usage," JPL IOM 335.1-11-93, 
May 21, 1993.                                                                 
                                                                              
The data are deliverable via electrical interface.                            
                                                                              
UTPM STOIC DATA FORMAT                                                        
                                                                              
UTPM STOIC data are available as ASCII files in Fortran Namelist format.  The 
data file consists of 88 card-image records. In Fortran Namelist format, each 
variable in a single record is of the form                                    
                                                                              
     variable(i) = value(i), value(i+1), value(i+2)...value(i+j-1),           
                                                                              
where i is an index running from 1 to 335 and j is the number of data values  
of the variable given on a single record. The subscripts i+1 through i+j are  
not given explicitly.                                                         
                                                                              
Two different UTPM STOIC files are available, identical except for the time   
tags, generally referred to as "seconds past 2000" or "seconds past 1950" (see
TIME below).  All time rates of change are with respect to International      
Atomic Time (TAI).                                                            
                                                                              
    Specific inputs are as follows:                                           
                                                                              
     First record:    TIMPOL    A label giving the date of the last input     
                                datum (LD) and the last date for which        
                                predictions are given, typically 30 days      
                                after the file is generated (PT). For Univac  
                                deliveries, the LD/PT portion names the       
                                Univac element. (See Figures TRK-2-21-1 and   
                                TRK-2-21-2 for LD and PT locations.) For      
                                UTPM STOIC files created since 1 May 1993, a  
                                variable called UT1TYP has been placed at     
                                the end of TIMPOL. Only two values are        
                                allowed, either UT1TYP=UT1R   or              
                                UT1TYP=UT1. Older UTPM STOIC files are all    
                                UT1R unless the string UT1 tidal terms        
                                appears at the end of TIMPOL. See the UT1R    
                                discussion in the Glossary.                   
                                                                              
                                Format: 16A4 (VAX 32-bit words) or 11A6       
                                (Univac 36-bit words)                         
                                                                              
     Records 2-14:  IT(i),      Thirteen calendar dates, one date per         
                    i = 1-39    record, that apply to all remaining data in   
                                the record. Epoch for those data is at 0 hr   
                                on the given date. (The purpose of these      
                                values is to improve human readability; they  
                                are not used by programs that read this       
                                file.)                                        
                                                                              
                                Format: YYMMDD                                
                                                                              
                    TP(i),     Time tags and TAI-UTC values and rates for     
                    i = 1-39   13 dates. (It is here that leap seconds        
                               appear. See Appendix.)                         
                                                                              
                               Format:  TP(i) = TIME, TAI-UTC, UTCDOT         
                                                                              
                    where      TIME = Time tag for the remaining data, in     
                                      UTC seconds past 12:00 noon Jan. 1,     
                                      2000, or UTC seconds past 0 hours       
                                      Jan. 1, 1950 (+SSSSSSSSSSS.).           
                                      Programs that read this file use TIME   
                                      as epoch for all the remaining data     
                                      in the record. TIME must be a           
                                      multiple of 100 seconds.                
                                                                              
                               TAI-UTC = TAI-UTC at TIME (+SS.SSSSSS).        
                                                                              
                               UTCDOT = Rate of change of TAI-UTC at TIME,    
                                        in seconds/second (nnnnn.nnnnE-10).   
                                        Zero by definition since 1 Jan        
                                        1972; at that epoch the UTC second    
                                        was defined to have the same length   
                                        as the TAI second.                    
                                                                              
     Records 15-51: IT(i),     Calendar date for data in record, as           
                    i = 40-150 discussed above.                               
                                                                              
                    TP(i),     Time tags and TAI-UT1 or TAI-UT1R values       
                    i = 40-150 and rates for 37 dates.                        
                                                                              
                               Format:  TP(i) = TIME, UT1, UT1DOT             
                                                                              
                    where      TIME = Seconds past 2000 or 1950 (see          
                                      above.)                                 
                                                                              
                               TAI-UT1 = TAI-UT1 at TIME (+SS.SSSSSS).        
                                                                              
                               UT1DOT = Rate of change of (TAI-UT1) at        
                                        TIME, in seconds/second               
                                        (nnnnn.nnnnE-10).                     
                                                                              
     Records 52-88: TP(i),      Time tags and polar motion data for 37        
               i = 151-335      dates, usually the same dates as for UT1.     
                                                                              
                                Format:  TP(i) = TIME, X, XDOT, Y, YDOT       
                                                                              
                    where       TIME = Seconds past 2000 or 1950 (see         
                                       above.)                                
                                                                              
                                X = X coordinate of polar motion at TIME in   
                                    arc seconds (+.XXXXX).                    
                                                                              
                                XDOT = Rate of change of X at TIME in arc     
                                       seconds/TAI second (+.RRRRR-EE).       
                                                                              
                                Y = Y coordinate of polar motion at TIME in   
                                    arc seconds (+.YYYYY).                    
                                                                              
                                YDOT = Rate of change of Y at TIME in arc     
                                       seconds/TAI second (+.RRRRR-EE).       
                                                                              
Examples of these data may be found in Figures TRK-2-21-1 and TRK-2-21-2.     
                                                                              
                                                                              
                                                                              
Figure TRK-2-21-1. Format of UTPM STOIC data file with "seconds past 2000"    
time tags                                                                     
                                                                              
                                                                              
 TIMPOL='STOIC/KEOF.LD950322/PT950602 . PREDICTS->950602. UT1TYP=UT1R.',      
 IT(  1)=930910,TP(  1)= -199108800., 28.000000,    0.0000E-10,               
 IT(  4)=940701,TP(  4)= -173707200., 29.000000,    0.0000E-10,               
 IT(  7)=100101,TP(  7)=  315576000., 45.000000,    0.0000E-10,               
 IT( 10)=991231,TP( 10)=          0.,  0.000000,    0.0000E-10,               
 IT( 13)=991231,TP( 13)=          0.,  0.000000,    0.0000E-10,               
 IT( 16)=991231,TP( 16)=          0.,  0.000000,    0.0000E-10,               
 IT( 19)=991231,TP( 19)=          0.,  0.000000,    0.0000E-10,               
 IT( 22)=991231,TP( 22)=          0.,  0.000000,    0.0000E-10,               
 IT( 25)=991231,TP( 25)=          0.,  0.000000,    0.0000E-10,               
 IT( 28)=991231,TP( 28)=          0.,  0.000000,    0.0000E-10,               
 IT( 31)=991231,TP( 31)=          0.,  0.000000,    0.0000E-10,               
 IT( 34)=991231,TP( 34)=          0.,  0.000000,    0.0000E-10,               
 IT( 37)=991231,TP( 37)=          0.,  0.000000,    0.0000E-10,               
 IT( 40)=930910,TP( 40)= -199108800., 27.527470,  240.7390E-10,               
 IT( 43)=930928,TP( 43)= -197553600., 27.567560,  271.4260E-10,               
 IT( 46)=931016,TP( 46)= -195998400., 27.612490,  311.1530E-10,               
 IT( 49)=931103,TP( 49)= -194443200., 27.660101,  293.2580E-10,               
 IT( 52)=931121,TP( 52)= -192888000., 27.704720,  273.6060E-10,               
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
 IT(124)=950127,TP(124)= -155563200., 28.668550,  315.9780E-10,               
 IT(127)=950214,TP(127)= -154008000., 28.715870,  289.0080E-10,               
 IT(130)=950304,TP(130)= -152452800., 28.762859,  339.3200E-10,               
 IT(133)=950322,TP(133)= -150897600., 28.816549,  338.1390E-10,               
 IT(136)=950409,TP(136)= -149342400., 28.868320,  328.4500E-10,               
 IT(139)=950427,TP(139)= -147787200., 28.918819,  319.7110E-10,               
 IT(142)=950515,TP(142)= -146232000., 28.967529,  307.7830E-10,               
 IT(145)=950602,TP(145)= -144676800., 29.014490,  296.2670E-10,               
 IT(148)=100101,TP(148)=  315576000., 45.000000,  317.0000E-10,               
 IT(151)=930910,TP(151)= -199108800.,-.10100,0.12380E-08,0.33040,0.19430E-07, 
 IT(156)=930928,TP(156)= -197553600.,-.09540,0.27750E-08,0.36360,0.23730E-07, 
 IT(161)=931016,TP(161)= -195998400.,-.08280,0.84520E-08,0.39800,0.18670E-07, 
 IT(166)=931103,TP(166)= -194443200.,-.07040,0.19770E-07,0.42230,0.98470E-08, 
 IT(171)=931121,TP(171)= -192888000.,-.04420,0.84590E-08,0.44400,0.11020E-07, 
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
 IT(291)=950127,TP(291)= -155563200.,-.11650,0.95110E-08,0.47660,0.25570E-07, 
 IT(296)=950214,TP(296)= -154008000.,-.09380,0.16550E-07,0.50860,0.17200E-07, 
 IT(301)=950304,TP(301)= -152452800.,-.04970,0.39790E-07,0.53530,0.15100E-07, 
 IT(306)=950322,TP(306)= -150897600.,-.00290,0.32860E-07,0.54990,0.83750E-08, 
 IT(311)=950409,TP(311)= -149342400.,0.04950,0.34210E-07,0.55630,-.36730E-09, 
 IT(316)=950427,TP(316)= -147787200.,0.10220,0.33200E-07,0.54880,-.92200E-08, 
 IT(321)=950515,TP(321)= -146232000.,0.15150,0.29830E-07,0.52790,-.17490E-07, 
 IT(326)=950602,TP(326)= -144676800.,0.19390,0.24330E-07,0.49500,-.24590E-07, 
 IT(331)=100101,TP(331)=  315576000.,0.00000,0.00000E+00,0.25000,0.00000E+00, 
                                                                              
                                                                              
Figure TRK-2-21-2. Format of UTPM STOIC data file with "seconds past 1950"    
time tags.                                                                    
                                                                              
 TIMPOL='STOIC/KEOF.LD950322/PT950602 . PREDICTS->950602. UT1TYP=UT1R.',      
 IT(  1)=930910,TP(  1)= 1378771200., 28.000000,    0.0000E-10,               
 IT(  4)=940701,TP(  4)= 1404172800., 29.000000,    0.0000E-10,               
 IT(  7)=100101,TP(  7)= 1893456000., 45.000000,    0.0000E-10,               
 IT( 10)=991231,TP( 10)=          0.,  0.000000,    0.0000E-10,               
 IT( 13)=991231,TP( 13)=          0.,  0.000000,    0.0000E-10,               
 IT( 16)=991231,TP( 16)=          0.,  0.000000,    0.0000E-10,               
 IT( 19)=991231,TP( 19)=          0.,  0.000000,    0.0000E-10,               
 IT( 22)=991231,TP( 22)=          0.,  0.000000,    0.0000E-10,               
 IT( 25)=991231,TP( 25)=          0.,  0.000000,    0.0000E-10,               
 IT( 28)=991231,TP( 28)=          0.,  0.000000,    0.0000E-10,               
 IT( 31)=991231,TP( 31)=          0.,  0.000000,    0.0000E-10,               
 IT( 34)=991231,TP( 34)=          0.,  0.000000,    0.0000E-10,               
 IT( 37)=991231,TP( 37)=          0.,  0.000000,    0.0000E-10,               
 IT( 40)=930910,TP( 40)= 1378771200., 27.527470,  240.7390E-10,               
 IT( 43)=930928,TP( 43)= 1380326400., 27.567560,  271.4260E-10,               
 IT( 46)=931016,TP( 46)= 1381881600., 27.612490,  311.1530E-10,               
 IT( 49)=931103,TP( 49)= 1383436800., 27.660101,  293.2580E-10,               
 IT( 52)=931121,TP( 52)= 1384992000., 27.704720,  273.6060E-10,               
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
 IT(124)=950127,TP(124)= 1422316800., 28.668550,  315.9780E-10,               
 IT(127)=950214,TP(127)= 1423872000., 28.715870,  289.0080E-10,               
 IT(130)=950304,TP(130)= 1425427200., 28.762859,  339.3200E-10,               
 IT(133)=950322,TP(133)= 1426982400., 28.816549,  338.1390E-10,               
 IT(136)=950409,TP(136)= 1428537600., 28.868320,  328.4500E-10,               
 IT(139)=950427,TP(139)= 1430092800., 28.918819,  319.7110E-10,               
 IT(142)=950515,TP(142)= 1431648000., 28.967529,  307.7830E-10,               
 IT(145)=950602,TP(145)= 1433203200., 29.014490,  296.2670E-10,               
 IT(148)=100101,TP(148)= 1893456000., 45.000000,  317.0000E-10,               
 IT(151)=930910,TP(151)= 1378771200.,-.10100,0.12380E-08,0.33040,0.19430E-07, 
 IT(156)=930928,TP(156)= 1380326400.,-.09540,0.27750E-08,0.36360,0.23730E-07, 
 IT(161)=931016,TP(161)= 1381881600.,-.08280,0.84520E-08,0.39800,0.18670E-07, 
 IT(166)=931103,TP(166)= 1383436800.,-.07040,0.19770E-07,0.42230,0.98470E-08, 
 IT(171)=931121,TP(171)= 1384992000.,-.04420,0.84590E-08,0.44400,0.11020E-07, 
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
    .      .        .         .            .            .                     
 IT(291)=950127,TP(291)= 1422316800.,-.11650,0.95110E-08,0.47660,0.25570E-07, 
 IT(296)=950214,TP(296)= 1423872000.,-.09380,0.16550E-07,0.50860,0.17200E-07, 
 IT(301)=950304,TP(301)= 1425427200.,-.04970,0.39790E-07,0.53530,0.15100E-07, 
 IT(306)=950322,TP(306)= 1426982400.,-.00290,0.32860E-07,0.54990,0.83750E-08, 
 IT(311)=950409,TP(311)= 1428537600.,0.04950,0.34210E-07,0.55630,-.36730E-09, 
 IT(316)=950427,TP(316)= 1430092800.,0.10220,0.33200E-07,0.54880,-.92200E-08, 
 IT(321)=950515,TP(321)= 1431648000.,0.15150,0.29830E-07,0.52790,-.17490E-07, 
 IT(326)=950602,TP(326)= 1433203200.,0.19390,0.24330E-07,0.49500,-.24590E-07, 
 IT(331)=100101,TP(331)= 1893456000.,0.00000,0.00000E+00,0.25000,0.00000E+00, 
                                                                              
EOP DATA FORMAT                                                               
                                                                              
EOP data are available as ASCII files in Navigation Portable Namelist format. 
(Navigation Portable Namelist is a Namelist processor written and maintained  
by the Navigation Software Development Group.)  In addition to the inclusion  
of nutation parameters, the EOP file differs from the UTPM STOIC file in other
important ways:                                                               
                                                                              
The EOP file may be of any length, whereas the UTPM STOIC file is limited to  
13 records for TAI-UTC, 37 records for TAI-UT1, and 37 records for polar-     
motion X and Y.                                                               
                                                                              
All EOP data for a single time tag are in a single record, whereas the UTPM   
STOIC file has three different record types depending on the data type, as    
noted above.                                                                  
                                                                              
EOP time tags are expressed as Modified Julian Dates; UTPM STOIC time tags are
seconds past a particular epoch, such as 12:00 noon, 1 Jan. 2000, or 0 hours, 
1 Jan. 1950.                                                                  
                                                                              
All characters in a line following a dollar sign ($) are comments included for
convenience but ignored by all programs. Specific inputs are as follows:      
                                                                              
                                                                              
Records 1-6:         Labels and flags                                         
                                                                              
     Note: Adding blanks to fill out any of these labels or flags to their    
           full width of 6, 25, or 80 characters is unnecessary.              
                                                                              
     EOPLBL      character*80       This text label is used in identifying the
                                    EOP file; it provides the same information
                                    as the TIMPOL record in the UTPM STOIC    
                                    file.                                     
                                                                              
     EOPFNG      character*80       This text label gives the name of the     
                                    program used to produce the EOP file, the 
                                    date and time the file was generated, and 
                                    the date and time the program was linked. 
                                                                              
     EOPUT1      character*6        This flag indicates whether the data in   
                                    the file contain TAI-UT1 or TAI-UT1R. The 
                                    two possible values of this variable are  
                                    'UT1' and 'UT1R'.                         
                                                                              
     EOPTYP      character*6        This flag is used by the ODP to determine 
                                    whether to use the EOP array or the UTPM  
                                    STOIC (TP) array for the computation of   
                                    Earth orientation. The allowed values of  
                                    this variable are 'EOP' and 'STOIC'.      
                                                                              
     EOPTIM      character*25       Date and time (UTC) of creation of the EOP
                                    file (dd-mmm-yyyy hh:mm:ss.ffff).         
                                                                              
     EOPTRF      character*6        A label denoting the Terrestrial Reference
                                    Frame for station locations and site      
                                    velocities to which the EOP parameters    
                                    refer; currently the value assigned is    
                                    'ITRF93'.                                 
                                                                              
     EOPCRF      character*6        A label denoting the Celestial Reference  
                                    Frame to which the EOP parameters refer;  
                                    currently the value assigned is 'ICRF93'. 
                                                                              
Records 7, 8, ...:   EOP data                                                 
                                                                              
     EOP(j,i)    double-precision   Earth-orientation parameters in 7-element 
                 array (7,n)        records. There is no restriction on n.    
                                                                              
           EOP(1,i)                 Modified Julian Date (MJD) for the        
                                    remaining elements in the record (times   
                                    are UTC).                                 
                                                                              
           EOP(2,i)                 X coordinate of polar motion at time      
                                    EOP(1,i) in milliseconds of arc (mas). One
                                    mas is approximately 3 cm on the Earth's  
                                    surface.                                  
                                                                              
           EOP(3,i)                 Y coordinate of polar motion (mas).       
                                                                              
           EOP(4,i)                 TAI-UT1   or   TAI-UT1R (seconds).        
                                                                              
           EOP(5,i)                 TAI-UTC (seconds).                        
                                                                              
           EOP(6,i)                 Nutation correction dPsi (mas).           
                                                                              
           EOP(7,i)                 Nutation correction dEps (mas).           
                                                                              
                                                                              
                                                                              
EOP records are in strictly increasing time order and may have any record     
spacing (not necessarily uniform). The file must contain a record at the      
Modified Julian Date where each leap second occurs within the span of the     
file. The number of records required depends upon the data span and the       
desired accuracy. Random variations of UT1 are of the order of 0.07 ms in one 
day, corresponding to about 3 cm on the surface of the Earth. Systematic sub- 
daily tidal variations of both UT1 and polar motion exist, also with          
approximately 3-cm amplitudes. The spacing used in currently delivered EOP    
files is one day, to allow modeling inertial station locations with           
approximately 3-cm accuracy. The file format allows records to be more closely
spaced if greater accuracy is desired.                                        
                                                                              
                                                                              
A sample EOP file is given in Figure TRK-2-21-3.                              
                                                                              
Figure TRK-2-21-3.  Sample EOP file. October 1994 records (which are not      
typographical errors) indicate flexibility of format                          
                                                                              
 $  JPL Earth Orientation Parameter File                                      
 $  Last Data Point 20-MAR-1995                                               
 $  Predicts to     24-APR-1995                                               
 $                                                                            
 EOPLBL='EOP. LAST DATUM 20-MAR-1995. PREDICTS->24-APR-1995, UT1TYP=UT1.   '  
 EOPFNG='Enter MAKE_EOP 22-MAR-1995 00:37:34      linked 24-OCT-1994 16:22:56'
 EOPUT1='UT1'                                                                 
 EOPTYP='EOP'                                                                 
 EOPTIM='22-MAR-1995 00:37:34     '                                           
 EOPTRF='ITRF93'                                                              
 EOPCRF='ICRF93'                                                              
 $                                                                            
 $ MJD      PM x     PM y     TAI-UT1  TAI-UTC   dPsi     dEps                
 $          (mas)    (mas)     (sec)    (sec)    (mas)    (mas)               
 EOP=                                                                         
 49532.0,  140.00,  213.90,  28.214890,  28.0,  -23.54,   -7.18, $ 29-JUN-1994
 49533.0,  138.50,  212.40,  28.216150,  28.0,  -23.95,   -7.19, $ 30-JUN-1994
 49534.0,  137.00,  211.00,  28.217310,  29.0,  -24.12,   -7.14, $  1-JUL-1994
 49626.0,  -64.50,  198.10,  28.373960,  29.0,  -30.49,   -6.77, $  1-OCT-1994
 49641.0,  -98.20,  222.90,  28.411930,  29.,  -29.41,    -6.08, $ 16-OCT-1994
 49642.0,  -99.80,  225.30,  28.414420,  29.0,  -29.53,   -5.93, $ 17-OCT-1994
 49656.0, -130.90,  255.40,  28.445640,  29.0,  -28.15,   -5.76, $ 31-OCT-1994
 49663.0, -141.20,  270.80,  28.464470,  29.0,  -27.85,   -5.31, $  7-NOV-1994
 49670.0, -146.50,  289.10,  28.481500,  29.0,  -27.09,   -5.02, $ 14-NOV-1994
 49677.0, -151.90,  307.90,  28.496910,  29.0,  -26.84,   -4.99, $ 21-NOV-1994
 49684.0, -151.90,  327.70,  28.513890,  29.0,  -25.96,   -4.25, $ 28-NOV-1994
 49691.0, -151.70,  345.40,  28.531520,  29.0,  -25.83,   -4.27, $  5-DEC-1994
 49701.0, -153.80,  370.90,  28.555710,  29.0,  -26.00,   -4.04, $ 15-DEC-1994
 49716.0, -156.40,  411.20,  28.596170,  29.0,  -26.20,   -3.72, $ 30-DEC-1994
 49718.0, -152.90,  417.10,  28.601450,  29.0,  -26.02,   -4.09, $  1-JAN-1995
 49720.0, -148.70,  422.90,  28.606980,  29.0,  -25.76,   -3.66, $  3-JAN-1995
 49722.0, -144.60,  428.20,  28.612890,  29.0,  -25.09,   -3.72, $  5-JAN-1995
 49724.0, -141.30,  432.50,  28.618810,  29.0,  -25.51,   -3.72, $  7-JAN-1995
 49749.0, -115.60,  485.40,  28.682430,  29.0,  -26.59,   -3.85, $  1-FEB-1995
 49750.0, -115.70,  487.10,  28.685320,  29.0,  -26.41,   -3.91, $  2-FEB-1995
    .        .        .          .         .       .         .         .      
    .        .        .          .         .       .         .         .      
    .        .        .          .         .       .         .         .      
 49825.0,   75.00,  547.80,  28.892010,  29.0,  -26.64,   -8.35, $ 18-APR-1995
 49826.0,   77.80,  547.10,  28.894710,  29.0,  -26.74,   -8.57, $ 19-APR-1995
 49827.0,   80.50,  546.40,  28.897360,  29.0,  -26.71,   -8.60, $ 20-APR-1995
 49828.0,   83.30,  545.60,  28.900010,  29.0,  -26.65,   -8.57, $ 21-APR-1995
 49829.0,   86.00,  544.80,  28.902720,  29.0,  -26.58,   -8.51, $ 22-APR-1995
 49830.0,   88.70,  544.00,  28.905510,  29.0,  -26.50,   -8.44, $ 23-APR-1995
 49831.0,   91.40,  543.10,  28.908350,  29.0,  -26.33,   -8.37, $ 24-APR-1995
                                                                              
APPENDIX                                                                      
                                                                              
GLOSSARY                                                                      
                                                                              
Note: For more detailed and rigorous explanations for astronomical terms given
below, including specific references, the following two works are             
recommended:                                                                  
                                                                              
   Explanatory Supplement to the Astronomical Almanac, P. Kenneth             
   Seidelman, ed.; University Science Books, Mill Valley, California          
   (1992).                                                                    
                                                                              
   IERS Standards (1992), Dennis D. McCarthy, ed.; IERS Technical Note 13,    
   Observatoire de Paris, Paris (July 1992).                                  
                                                                              
                                                                              
CEP        Celestial Ephemeris Pole: A direction in space, which varies from  
           day to day, about which the Earth appears to rotate on any         
           particular day. The CEP differs from the instantaneous rotation    
           axis of the Earth by periodic terms with amplitudes less than 30   
           cm. It differs from the pole of the celestial reference frame      
           (ICRF pole; see below) by quantities given by the IAU standard     
           nutation and precessional models (IAU 1980 Theory of Nutation; IAU 
           1976 Precession) and the offsets (dEps and dPsi; see below) from   
           those models.                                                      
                                                                              
CIO        Conventional International Origin: The point on the Earth's crust  
           representing the mean location of the true pole during the years   
           1900 - 1905; also called the Mean Pole 1903.0. Formerly used as    
           the terrestrial reference pole.                                    
                                                                              
dEps       Delta Epsilon: The obliquity component of the offset of the CEP    
           from the direction given by the IAU standard nutation and          
           precessional models, referred to the ICRF (see below).             
                                                                              
dPsi       Delta Psi: The offset in the ecliptic-longitude direction of the   
           CEP from the direction given by the standard nutation and          
           precessional models.                                               
                                                                              
IAU        International Astronomical Union.                                  
                                                                              
ICRF       IERS Celestial Reference Frame: A celestial coordinate system,     
           updated yearly by the IERS, based on a set of VLBI-determined      
           coordinates of compact extragalactic radio sources.                
                                                                              
IERS       International Earth Rotation Service: An organization that started 
           operation on 1 January 1988, replacing the earth-rotation section  
           of the Bureau International de l'Heure (BIH) and the International 
           Polar Motion Service (IPMS).                                       
                                                                              
IRM        IERS Reference Meridian: Reference meridian of the ITRF (see       
           below).                                                            
                                                                              
IRP        IERS Reference Pole: Reference pole of the ITRF (see below).       
                                                                              
ITRF       IERS Terrestrial Reference Frame: A terrestrial coordinate system, 
           updated yearly by the IERS, implicitly defined by a standard set   
           of station-location coordinates. The directions of its axes are    
           continuous with those of the previously used BIH Terrestrial       
           System.                                                            
                                                                              
KEOF       Kalman Earth Orientation Filter: An operational program that       
           produces smoothed and predicted estimates of earth-orientation     
           quantities for the DSN and flight project navigation teams.        
                                                                              
MJD        Modified Julian Date: A shortened version of Julian Date used for  
           convenience. MJD = Julian Date - 2400000.5.                        
                                                                              
Nutation   The action of the sun and moon on the Earth's equatorial bulge     
           causes small variations in the direction of the CEP. The short-    
           period (periods less than or equal to 18.6 years) portion of these 
           variations is called nutation; the long-period portion is called   
           precession, and is treated as secular (nonperiodic).               
                                                                              
ODP        Orbit Determination Program. The operational program used by JPL   
           navigation teams to determine spacecraft orbits, planetary         
           gravitational harmonics, and many other parameters.                
                                                                              
Precession See Nutation (above).                                              
                                                                              
STOIC      Standby Timing Operations In Contingencies. The program used to    
           generate the UTPM STOIC files.                                     
                                                                              
TAI        International Atomic Time (French word order): A time scale        
           determined by the International Bureau of Weights and Measures     
           (BIPM; French word order) from analysis of data from, and          
           intercomparison of, many atomic clocks in laboratories around the  
           world. Its unit interval is exactly one SI second at sea level.    
                                                                              
UTC        Coordinated Universal Time: Civil time, formerly called GMT. A     
           time scale running at the same rate (by definition) as TAI, except 
           for the introduction of leap seconds by the IERS as required to    
           keep UTC within 0.9 s of UT1.                                      
                                                                              
UT1        Universal Time 1: A measure of the instantaneous rotation angle of 
           the Earth, determined from astronomical and satellite observations 
           corrected for polar motion and measured in time units; also        
           formerly called GMT. It is related to the direction of the IRM in  
           the ICRF, measured around the CEP axis.                            
                                                                              
UT1R       UT1 with the effects of short-term tides removed. Short-term tidal 
           effects on UT1 have periods ranging from approximately 5 to 35     
           days. Long-term tidal effects have periods ranging from            
           approximately 91 days to 18.6 years, and are included in UT1R. The 
           quantities noted as "UT1" in the UTPM STOIC file description       
           or in the EOP file description will always be either all UT1 or    
           all UT1R in a particular file.                                     
                                                                              
X,Y        Coordinates of the Celestial Ephemeris Pole relative to the IERS   
           Reference Pole. X is measured along the IRM; Y is measured along   
           the meridian 90 degrees W of the IRM.