PDS_VERSION_ID        = PDS3                                                  
RECORD_TYPE           = STREAM                                                
OBJECT                = TEXT                                                  
  INTERCHANGE_FORMAT  = ASCII                                                 
  PUBLICATION_DATE    = 2001-09-01                                            
  NOTE                = "N/A"                                                 
END_OBJECT            = TEXT                                                  
                                                                              
END                                                                           
                                                                              
1. Introduction                                                               
                                                                              
This document provides an overview of the Near Earth Asteroid                 
Rendezvous Gamma-Ray Level 2 Observation Log archive.  These                  
documents describe the systems that were used to command and                  
control the spacecraft during times when XGRS was controlling                 
attitude, as well as commands that were used to configure the                 
instrumentation during the orbital encounter.                                 
                                                                              
                                                                              
2. Directory Contents                                                         
                                                                              
Three types of files are included in this directory:                          
                                                                              
a. XGRS_COMMAND_DESC.*    Describes the Observation Log macro names           
                          and configuration parameters.                       
                                                                              
b. XGRS_INST_USER_GUIDE4* Commanding and CAS generation for                   
                           instrument and commanding of spacecraft.           
                           Lists formats and other higher level               
                           issues for team members to build                   
                           instrument control macros.                         
                                                                              
c. XGRS_OBSLOG*           Actual Observation Log of dates and times           
                           of command macros that were executed by            
                           the spacecraft and instrument systems.             
                                                                              
Also included are label files for each file type.  

Operations log for the XGRS instrument during the orbital encounter with the Eros433 Asteroid. The table is text and proceeds in time from top (beginning of mission) to bottom (end of mission).  Each entry (row) is the instrument controlmacro that was issued at the identified time. PARM 1 to 6 fields show the macro configuration parameters that were issued.
                  
        COL_NUM     NAME             DESCRIPTION
        1           XGRS_COMMAND_ID  XGRS CAS or MACRO Identifier
        2           XGRS_COMMAND     Macro name
        3           XGRS_MODE        Macro State change
        4           YEAR             Year, 4 chars
        5           DOY              Day of year, length 1 to 3 chars
        6           HOUR_MIN_SEC     Hour Min and Sec, 7 or 8 chars
        7           PARM1            Depends on the command issued
        8           PARM2            Depends on the command issued
        9           PARM3            Depends on the command issued
        10          PARM4            Depends on the command issued
        11          PARM5            Depends on the command issued
        12          PARM6            Depends on the command issued                           
                                                                              
3. Cognizant Persons                                                          
                                                                              
NEAR/GRS data were provided by Jacob Trombka, NEAR XGRS Team Leader:          
                                                                              
Jacob Trombka                                                                 
Building 2, Rm# 165                                                           
Code 691, Astrochemistry Branch                                               
NASA/Goddard Space Flight Center                                              
Greenbelt, MD 20771.                                                          
                                                                              
jack.trombka@gsfc.nasa.gov                                                    
301-286-5941                                                                  
                                                                              
This volume was designed and produced by:                                     
                                                                              
Tim McClanahan                                                                
Building 2, # 166                                                             
Code 691, Astrochemistry Branch                                               
NASA/ Goddard Space Flight Center                                             
Greenbelt, MD 20771