EDPS Astrometry (AST) Pipeline Reference Manual

Contents

Astrometry Pipeline Overview

The need for an Astrometry Pipeline

The Astrometry Pipeline is the Pipeline within the EDPS that produces FITS format products for each astrometry observation performed by HST. The FITS filers are used by the Institute FGS instrument team to monitor the operation of the three FGS and to perform science with the FGS related data.

Intended Audience and Scope

This Reference Manual is intended primarily to give OPUS Operations Personnel information needed to understand the operation of the EDPS Astrometry Pipeline. This includes information on the Astrometry Pipeline Input and Output products, the directories and files used, and the processes involved. Hopefully, as envisioned, this manual will be a dynamic document that is updated when Astrometry Pipeline changes are made.

Astrometry Pipeline Dependencies

Being one of five pipelines that compose the EDPS, The Astrometry pipeline is not a stand-alone pipeline in and of itself. In order for the Astrometry Pipeline to function, processes contained in other EDPS pipelines must first execute correctly. In fact, the Astrometry pipeline must be the last to run in the sequence of the five pipelines. In regards to how they provide for the astrometry pipeline, and for the astrometry pipeline processing to be successful, the five EDPS pipelines must execute in the following sequence:
  1. PASS Data Receipt(PDR) This pipeline receives Science Mission Schedule (SMS) information from the PASS system and uses the information to populate database relations that processes in the astrometry pipeline rely on. The relations provide information such as astrometry observation start and stop times.
  2. Engineering Data Receipt(EDR) This pipeline receives compressed engineering telemetry files from CCS and uncompresses them so they can be read by the FOF Conversion pipeline. The FOF pipeline in turn extracts telemetry parameters of interest from the telemetry files and provides the telemetry of interest to the astrometry pipeline. The astrometry pipeline uses the telemetry to generate its output FITS file products.
  3. FOF Conversion(FOF) This pipeline dredges the engineering telemetry files received from CCS for astrometry related telemetry parameters of interest. The telemetry parameters of interest are extracted and stored into intermediary files (tyyyydddhhmm.ast) which are read by the astrometry pipeline and their data used to generate the astrometry FITS file output products.
  4. Fine Guidance Sensor(FGS) This pipeline produces jitter products for HST observations. In producing these products however, various values that are also required in the astrometry pipeline are calculated. These values are provided to the astrometry pipeline in the form of keyword/value pairs contained in the ast_jitter_kw relation. The keyword/value pairs end up in the headers of the astrometry FITS file products.
  5. Astrometry(AST) Pipeline - This pipeline produces Astrometry FITS File products.
Also, the Astrometry Pipeline and the OPUS EDPS in general for that matter are highly dependent upon database interaction; see Astrometry Pipeline Database Usage. In order for the astrometry pipeline database interaction to occur correctly, the processes in the pipeline should be executed in a pipeline mode as opposed to an interactive mode. Typically, as specified by the OK_TO_UPDATE_DATABASE mnemonic in process resource files, processes that run in interactive mode are prohibited from performing database updates. Therefore, to ensure correct operation of the pipeline, !!! ALL ASTROMETRY PIPELINE PROCESSES SHOULD BE RUN ONLY IN THE PIPELINE MODE !!!.

Astrometry Pipeline Nominal Operational Description

After the PDR, EDR, and FOF pipelines have successfully executed for the time period covering a specific SMS, the Astrometry Pipeline is ready to generate FITS File output products for all astrometry observation contained within the SMS. Astrometry pipeline processing is triggerred by the appearance of astrometry telemetry files in the AST_TELEM_DIR directory. Then, a number of astrometry processes are triggerred in sequence to extract astrometry related data from the input telemetry files and from various database relations. This astrometry related data is accumulated in intermediary files in the AST_RAW_DIR directory. These intermediary files are then used by the FGSAST process to actually produce the astrometry FITS file products that get written to the AST_OUTPUT_DIR directory. Requests are then made to archive the astrometry products. Files that get produced to track the progress of archive requests and responses are written to the AST_AREQ_DIR, AST_ARSP_DIR, and AST_LOG_DIR directories. Once the astrometry products have successfully archived, astrometry "clean-up" processes are triggerred to delete the intermediary files used to produce the products, to delete the products themselves, and to delete the OSFs that were generated for each observation processed. In addition, determinations are made with regard to whether any of the input astrometry telemetry files are needed for processing other astrometry observations. The telemetry files deemed to be no longer needed will be deleted along with their corresponding OSFs.

Astrometry Pipeline Directories and Files

Astrometry Pipeline Processes

Astrometry Pipeline Processes Overview

The Astrometry Pipeline is composed of the following 12 processes:

  1. ASTPOL - polls the AST_TELEM_DIR directory for astrometry telemetry files produced by the EDPS FOF Pipeline and creates an 'eng' class osf for each telemetry file found
  2. RAHOLD - queries database to find out if any astrometry observations occured during the time frame of the telemetry files found by the ASTPOL process. Also determines if any of the observations require telemetry files that have not yet arrived before processing can proceed. 'ast' class OSF's are created for each observation that is ready to be processed.
  3. RAWAST - generates the telemetry derived astrometry keyword file (fpppssoom.akx) and the telemetry group data file (fpppssoom.arx) file used by the FGSAST Process to produce the astrometry output FITS file products
  4. ASTKWD - generates the database derived astrometry keyword file (fpppssoom.agx) used by the FGSAST Process to produce the astrometry output FITS file products
  5. SS_AST - generates the database derived astrometry support schedule file (fpppssoom.dgx) used by the FGSAST Process to produce the astrometry output FITS file products
  6. FGSAST - produces astrometry FITS file output products
  7. ASTREQ - generates request to archive astrometry FITS file products
  8. ASTRSP - processes responses to archive requests
  9. ASTCLN - deletes the files that were used in producing the astrometry output products; i.e., the fpppssoom.ark, fpppssoom.akx, fpppssoom.agx, fpppssoom.dgx, and fpppssoom.trx files and the products themselves; i.e., fpppssoom_a1f.fits, fpppssoom_a2f.fits, fpppssoom_a3f.fits, fpppssoom_dmf.fits, and fpppssoom_trl.fits after the products have been successfully archived.
  10. ASTFIN - determines if the astrometry telemetry file currently being processed is needed to process any other astrometry observations. If the telemetry file is no longer needed, its 'eng' class OSF is set to complete to indicate that the telemetry file can be deleted.
  11. DL_AST - deletes astrometry telemetry files; i.e., (tyyyydddhhmm.ast_done) files that are no longer needed for astrometry processing
  12. ASTDEL - deletes 'eng' and 'ast' class osf's from the astrometry pipeline after the astrometry processing has completed

Astrometry Pipeline Processes Details

ASTPOL Process details

RAHOLD Process details

RAWAST Process details

ASTKWD Process details

SS_AST Process details

FGSAST Process details

ASTREQ Process details

ASTRSP Process details

ASTCLN Process details

ASTFIN Process details

DL_AST Process details

ASTDEL Process details

Astrometry Pipeline Database usage

Database Relations Accessed

Database Querries Performed

Database Relations accessed

product_eng_map Relation

     This relation is used to identify the engineering telemetry files that may be required for FGS, GSA or 
     AST product generation. It is used to simplify creation and collection of telemetry for processing. 
     When a product has no eng_ready = N flags, then the OSF for the product can be created using the product 
     rootname.
     
     The astrometry Pipeline RAHOLD and ASTFIN processes use this relation.     


       	Field name           type/size	 description  
        ----------           ---------   -----------
        product_rootname     C14         IPPPSSOOT for jitter or astrometry products;
                                         GYYYYDDDHHMMSS for GS acquisition data
 
        product_type         C3          FGS for jitter, AST for astrometry, or GSA for GS 
                                         acqusition data
 
        eng_rootname         C12         TYYYYDDDHHMM, rootname of the ENG telemetry file

 
        eng_ready            C1          (Y/N), 'N' indicates the telemetry file eng_rootname is not
                                         yet recognized as ready for this product_type. 'Y' indicates
                                         that the processing for this product type has recognized
                                         the presence of eng_rootname. Having separate control for
                                         each product type simplifies initiation of processing. "

product_status Relation

     This relation is used to identify the completion status of all FGS, AST, and GSA products in order to 
     control telemetry file cleanup.  The records are created with N for complete_flag. This relation is 
     designed to be joined to product_eng_map to determined when all the products, identified in 
     product_eng_map by product_type and product_rootname, have been marked completed.  

     For reprocessing, all the products to be reprocessed should have the complete_flag interactively reset 
     to N. For replans, any records for dataset no longer present in qolink. must be deleted. Only one record 
     for each product and type is allowed. "

     The astrometry Pipeline RAHOLD and ASTFIN processes use this relation.     


       	Field name           type/size	 description  
        ----------           ---------   -----------
	product_rootname     C14         IPPPSSOOT for jitter or astrometry products;
                                         GYYYYDDDHHMMSS for GS acquisition data

        product_type         C3          FGS for jitter, AST for astrometry, or GSA for GS 
                                         acqusition data

        complete_flag        C1          (Y/N) set to Y by cleanup software indicating this dataset has been 
	                                 processed and no longer prevents cleanup of telemetry files

qolink_sms Relation

     This relation is used to provide DADS and OPUS with the SMS_ID for any observation in 
     the support schedule. It can be used to list all observations and association
     products for a particular SMS_ID. It contains a status field to identify observation 
     or product archive success or unavailability.

     The astrometry Pipeline RAWAST and ASTRSP processes use this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
		                         be assigned a unique 3 character base 36 program identifier.
		                         Is is used for identification of proposals by spacecraft 
                                         and OPUS software. It is also used in the OPUS and DADS 
                                         rootname for all archived science data files.
					 
        obset_id             C2          An observation set is a collection of one or more alignments
	                                 that are grouped together based on FGS pointing requirements.  
					 That is, if multiple alignments can all be executed using the 
					 same guide star pair, they are grouped into the same observation set.

        ob_number            C3          Observations are numbered sequentially throughout an observation set. 
	                                 An ob_number is _NOT_ the same as an obset_ID. The third character is
					 only used for association products
 
        sms_id               C9          The C&C list is a major data structure within SPSS that 
		                         contains information on 'candidates' and the 'calendar'.
					 The candidate data, often referred to as the candidate pool, are 
					 scheduling units and their associated  observation set, alignment, and
					 target data.  The calendar is a timeline of activities that are laid 
		                         down by the SPSS scheduling utilities.  When a C&C List is saved in 
    					 SPSS it receives an identifier (sms_id)

	status               C1          The condition or availability for archiving is indicated
                                         by a status code with the following definition:
		
                                           U - Unexecuted - the initial condition for exposures or
                                               products that will be archived independently of
                                               associations
 
                                           M - Member - the initial condition for exposures that
                                               are only archived within an association product

                                           N - Not available - set by operations to indicate 
                                               exposures or products that cannot be generated

                                           E - Executed and archived successfully				 

        inst                 C1          One character identifier for the instrument used for the science 
	                                 observation. The relation between this value and the names in 
					 qobservation.si_id are: 

                                           1 = 1     2 = 2     3 = 3     J = ACS     N = NIC     O = STIS
                                           U = WFII  V = HSP   W = WFPC  X = FOC     Y = FOS     Z = HRS

        tag                  C1          Flags observation as a target acquisition.
                                           Y - The qobservation.target_acqmode field is 01 or 02.
                                               This observation is a target acquisition


        ocx_expected         C1          Flags this observation as real time (mode 1) target acq.
                                           Y - The qobservation.target_acqmode field is 01.
                                               This observation is a mode 1 (real time) target acquisition 
					       image

        pdq_created          C1          indicates if the OPUS pipeline has created a PDQ file for this 
	                                 observation.  The value of this column is an alphanumeric code that
                                         indicates the status, real or inferred, of the PDQ file for the 
					 observation

        oms_archived         C1          indicates if the OMS pipeline has successfully achived an 
	                                 observation log for this observation. 
                                           X - The data assessment software has validated existence of the
					   OMS observation log for this observation in DADS

        rti_checked          C1          indicates if OPUS staff has checked for existence of real time
                                         information for this observation.
                                           X - OPUS staff has run RTI_CHECK software for this observation

        ocx_appended         C1          indicates if an OCX file has been appended to the PDQ file.
                                         The value of this field is an alphanumeric code that indicates 
					 that the data assessment software has located an OCX file (and 
					 the type of file) for this observation and has appended it to 
					 the PDQ file

        assessed             C1          indictaes if this observation has been assessed for procedural 
	                                 quality. The value of this column is an alphanumeric code that
                                         summarizes the essentials of the assessment process."

        dq_archived          C1          indicates the archive status of the procedural data quality 
	                                 file(s).  The value of this column is an alphanumeric code that
                                         indicates the archive status of the PDQ (and optionally
                                         the OCX) file of this observation

        start_time           C17         This field (format: yyyy.ddd:hh:mm:ss) contains either the 
	                                 planned or actual start time of the observation. The time_type 
					 field indicates the source of the time.

        end_time             C17         This field (format: yyyy.ddd:hh:mm:ss) contains either the 
	                                 planned or actual end time of the observation. The time_type 
					 field indicates the source of the time.

        time_type            C1          (P/A) When this field is P for planned, start_time and end_time 
	                                 are generated from SPSS planning data and the accuracy is 
					 questionable. When this field is A for actual, start_time and 
					 end_time have been updated by the OPUS pipeline using science 
					 data.

msc_ast_obset Relation

     This relation is used to contain the obset level data for astrometry. The event time is taken from the time found in
     the MSC file but there is no msc_events record for this event. The fields are used to set 
     astrometry keywords.
     
     The astrometry Pipeline RAWAST and ASTKWD processes use 
     this relation.
          
     
       	Field name           type/size	 description  
        ----------           ---------   -----------
        event_time           C20         the time within a hundreth of a second for each obset
	                                 (YYYY.DDD.HH.MM.SS.CC)

        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
		                         be assigned a unique 3 character base 36 program identifier.
		                         Is is used for identification of proposals by spacecraft 
                                         and OPUS software. It is also used in the OPUS and DADS 
                                         rootname for all archived science data files.

        obset_id             C2          An observation set is a collection of one or more alignments
	                                 that are grouped together based on FGS pointing requirements.  
					 That is, if multiple alignments can all be executed using the 
					 same guide star pair, they are grouped into the same observation set.

        fgs                  C1          FGS number, 1 2 or 3, or 0 for all

        param_name           C8          Keyword name or keyword related parameter name
	
        param_value          C20         Formatted value of parameter

eng_trigger Relation

     This relation is used to name the trigger codes so that reports can use a name rather than a 
     number and to provide standardized names for constants used in header files for software 
     processing GS acquisition telemetry.  These triggers are also used in astrometry processing.

     The astrometry Pipeline RAWAST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        eng_trigger          I4          A numeric code indicating the processing to be performed when
	                                 a change in telemetry value has been detected. A zero value is
					 not a trigger but that entry is used to indicated that the 
					 telemetry value should be saved
			 
	eng_trigger_name     C30         A name for a trigger that implies the purpose of the 
	                                 processing of the telemetry item

eng_telem_name Relation

     This relation is used to identify the engineering telemetry items in engineering files by a name 
     that is descriptive.  The name has a four character prefix that indicates the shuttle mnemonic 
     that corresponds to the telemetry definition. The mnemonic may be assigned to more than one 
     CCS telemetry item because of the use in different telemetry formats. In general when two 
     telemetry items have the same meaning and raw values, the lower numerical value is used.

     The astrometry Pipeline RAWAST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        eng_number           I4          A small positive value used only in FGS or AST eng files 

        telem_name           C30         A name having the short_mnemonic as a prefix but including a 
	                                 description useful for validation

eng_telem_use Relation

     This relation is used to identify the telemetry used to generate various products, and to indicate
     trigger codes to be used when a changed value has been detected. A trigger code of zero indicates
     that the latest value must be saved but no immediate processing is required.  If there is no entry
     in this table for a particular class then that telemetry item should be ignored. The names of the
     telemetry items are found in the eng_telem_name table.  The names of the trigger codes are found 
     in the eng_trigger table.

     The astrometry Pipeline RAWAST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        product_type         C3          FGS for jitter, AST for astrometry,  GSA for GS acqusition 
	                                 data, or OTM for STIS temperatures

        eng_number           I4          A small positive value used only in FGS or AST engineering 
	                                 telemetry files

        eng_trigger           I4         A numeric code indicating the processing to be performed when
	                                 a change in telemetry value has been detected. A zero value is
					 not a trigger but that entry is used to indicated that the 
					 telemetry value should be saved

ast_jitter_kw Relation

     This relation is used to provide data calculted by the EDPS FGS Pipeline JITTER process to the AST 
     pipeline. The data is in the form of named keyword values. For flexibility, this table allows an 
     arbitrary number of keywords to be accessed by the programmatic IDs of the astrometry dataset.

     The astrometry Pipeline ASTKWD process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
		                         be assigned a unique 3 character base 36 program identifier.
		                         Is is used for identification of proposals by spacecraft 
                                         and OPUS software. It is also used in the OPUS and DADS 
                                         rootname for all archived science data files.
					 
        obset_id             C2          An observation set is a collection of one or more alignments
	                                 that are grouped together based on FGS pointing requirements.  
					 That is, if multiple alignments can all be executed using the 
					 same guide star pair, they are grouped into the same observation set.

        ob_number            C3          Observations are numbered sequentially throughout an observation set. 
	                                 An ob_number is _NOT_ the same as an obset_ID. The third character is
					 only used for association products

        keyword_name         C8          The name of the keyword which has the keyword_value

        keyword_value        C68         The value of the keyword_name. The longest string allowed by
	                                 FITS is 68 characters. Most keywords have values that are 
					 less than 20 characters

dataset_link Relation

     This relation is used to link the dataset rootname to programmatic ids with keys to facilitate
     joins to other relations.

     The astrometry Pipeline ASTKWD process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        dataset_rootname     C9          IPPPSSOOT for jitter or astrometry datasets

        dataset_type         C3          Either FGS or AST, for FGS obslogs or astrometry, respectively

        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
		                         be assigned a unique 3 character base 36 program identifier.
		                         Is is used for identification of proposals by spacecraft 
                                         and OPUS software. It is also used in the OPUS and DADS 
                                         rootname for all archived science data files.
					 
        obset_id             C2          An observation set is a collection of one or more alignments
	                                 that are grouped together based on FGS pointing requirements.  
					 That is, if multiple alignments can all be executed using the 
					 same guide star pair, they are grouped into the same observation set.

        ob_number            C3          Observations are numbered sequentially throughout an observation set. 
	                                 An ob_number is _NOT_ the same as an obset_ID. The third character is
					 only used for association products

qobservation Relation

     This relation contains Support Schedule observation records from Science Mission Schedules.  The
     relation is an SPSS maintained relation with a lot of fields.  Since only the target_id is needed
     for astrometry processing; only that file will be described.

     The astrometry Pipeline ASTKWD and SS_AST processes uses 
     this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        target_id            C15         id of target for astrometry observation

msc_ast_observe Relation

     This relation is used to contain the observation data for astrometry. The event time is taken 
     from the time found in the MSC file but there is no msc_events record for this event. The fields
     are used to set astrometry keywords.

     The astrometry Pipeline ASTKWD process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        event_time           C20         YYYY.DDD.HH.MM.SS.CC the time within a hundreth of a second 
	                                 for each obset

        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
		                         be assigned a unique 3 character base 36 program identifier.
		                         Is is used for identification of proposals by spacecraft 
                                         and OPUS software. It is also used in the OPUS and DADS 
                                         rootname for all archived science data files.
					 
        obset_id             C2          An observation set is a collection of one or more alignments
	                                 that are grouped together based on FGS pointing requirements.  
					 That is, if multiple alignments can all be executed using the 
					 same guide star pair, they are grouped into the same observation set.

        ob_number            C3          Observations are numbered sequentially throughout an observation set. 
	                                 An ob_number is _NOT_ the same as an obset_ID. The third character is
					 only used for association products

        fgs                  C1          FGS number, 1 2 or 3, or 0 for all

        param_name           C8          Keyword name or keyword related parameter name

        param_value          C20         Formatted value of parameter

aperture_def Relation

     This relation defines the size, shape, and location of the science instrument apertures.  
     Three fundamental cartesian coordinate systems are used.  The first of these systems is 
     the V1-V2-V3 system.  It is the three dimensional 'vehicle' coordinate system.  The V2-V3 
     plane defines the 'aperture' plane.  The other two fundamental coordinate systems are defined 
     in the aperture plane relative to the V1,V2,V3 frame. 
                       
     The Science Instrument Coordinate System (SICS) is actually a set of coordinate
     systems; one or more for each science instrument.  Coordinates are expressed
     in arcseconds.  Generally there is one SICS defined for each aperture.

     The Science Aperture Coordinate System (SIAS) is similar to the SICS except the 
     coordinates are expressed in units appropriate for the instrument (i.e. pixels).  
     SIAS is not used in SPSS.  

     This relation does NOT defines the conversion factors needed to transform
     coordinates expressed in one coordinate system to another.   See the SPSS 
     Algorithms document (SE-06-02 Appendix B) for a complete discussion of these 
     transformations and see relation sics_sias_coef for the conversion coefficients.

     The astrometry Pipeline SS_AST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        due to the large number of fields, they will not be specified here.  The OPUS "sddl" 
	directory provides descriptions of this relation and all of its fields and can be
	referenced if so desired.

kw_source Relation

     This relation specifies the source of selected keywords.  The source may be specified in three 
     ways, from the PDB (Project Database), from the PMDB (Proposal management Database), or as a 
     difference calculation.

     In the first case (PDB) the source of the keyword will be the name of a mnemonic as 
     specified in the EUDL.DAT file of the PDB.  The OPUS software will look up the location
     of that mnemonic in the yurintab relation.  If it is desired to convert the value of the 
     mnemonic to a string (discrete conversion) or to engineering units (linear or polynomial 
     conversion), then the second field (subsource) specifies the 8 character mnemonic of a 
     conversion.  See the description of conv_discrete, conv_linear, and conv_polynomial.

     In the second case (PMDB) the source field is the name of a database relation in the PMDB.  
     The subsource specifies the name of the field in that relation.  Only relations which can 
     be joined with the relation qolink on the basis of program_id, obset_id and ob_number can 
     be used.  There is a special case of deep relations like qesiparm.  In this case there is 
     only a field for si_par_name and si_par_value, both of which are string fields.  To obtain a 
     value from such a deep relation, specify the name of the parameter in a form (usually uppercase) 
     that will match the value in the database.

     Finally, for keywords which are simply differences between two already dredged keywords, only the
     names of the subtrahend and minuend mnemonics are required for the source and subsource fields.

     The astrometry Pipeline SS_AST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        instrument           C3          short instrument name

        keyword              C8          Name of the keyword

        sourcetype           C8          which kind of source applies (PDB, PMDB, DELTA)

        source               C30         source name: mnemonic, relation, subtrahend

        subsource            C30         specify: conversion mnemonic, fieldname or parameter name,
				         minuend mnemonic

cgg1_keyword Relation

 
     This relation provides keywords to be written to FITS file products during various pipeline 
     'Generic Conversion' processing.

     The astrometry Pipeline SS_AST and FGSAST
     processes use this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        instrument           C3          instrument to which the keyword is associated:
                                         hsp, wfc, foc, fos, hrs, wfII, fgs, acs, nic, sti

        file_type            C3          generic file type.  values are:
                                           shp (standard header packet),
                                           udl (unique data log);
                                           dsk (digital sky), dst (digital star),
                                           ask (analog sky),  ast (analog star),
                                           asd (area scan/digital), asa (area scan/analog);
                                           ext (extracted data), sci (science data);
                                           shl (science header line), stl (science trailer line);
                                           img (image)

        order_index          I4          an index defining the keyword order in the relation;
                                         it is used to order the appearance of keywords in the header
					 file to which it will be written 

        fixed_index          I4          this item should be thought of as a map of a fixed index
                                         for a keyword into a value in the sequence 1,2,...,n.  the
                                         fixed index is used to indicate a particular keyword

        keyword_str          C8          keyword character string

        keyword_typ          C3          data type of the keyword value

        keyword_val          C20         keyword value

        comment_str          C72         comment character string

        cnv_flag             C1          flag stating whether to automatically convert keyword

        optional             C1          indicates whether this keyword is an optional one. If an 
	                                 optional keyword has a blank value (restricted to strings), 
					 then that keyword will be omitted from the header

cgg4_order Relation

 
     This relation provides information on the groupings and ordering of keywords to be written to the FITS file
     produced by the FGSAST process.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        instrument           C3          instrument to which the keyword is associated:
                                         hsp, wfc, foc, fos, hrs, wfII, fgs, acs, nic, sti
        header_type          C36         The name of the FITS header. eg: NIC_SPT_PRIMARY
        ftype_order          I2          The order in which to put the following section
        cgg1_instr           C3          The cgg1_keyword relation instrument name.  This
			                 can be the same as 'instrument' above, or another
			                 name such as SSY or GEN."
        cgg1_ftype           C3          The cgg1_keyword relation 'file_type' specification
			                 for this section of keywords

si_aperture Relation

     This relation provides data values to be used in computing the aperture position and orientation
     for EDPS jitter files or OPUS target acquistion software, where the use-date refers to the start
     time of the first SMS which used these values.

     The astrometry Pipeline SS_AST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        si_aper_id           C10         si aperture identifier: si_name + si_aperture the relation is
	                                 indexed by the si identifier 

        use_date             C17         usage date (yyyy.ddd:hh:mm:ss) at SMS start, before which the
	                                 data for this aperture must not be used

        parity               I2          +1/-1... parity value used in the transformation from the sics
	                                 to the v2v3 syste

        v2_of_ref            R8          v2 coordinate of aperture reference point in arc seconds

        v3_of_ref            R8          v3 coordinate of aperture reference point in arc seconds

        pixel_incr           R8          pixel increment in arc seconds

        line_incr            R8          line increment in arc seconds

        ang_inc_pix          R8          angle, in degrees, from v3 to the line of increasing pixels,
	                                 positive counterclockwise viewed along positive v1 axis

        ang_inc_line         R8          angle, in degrees, from v3 to the line of increasing lines, 
	                                 positive counterclockwise viewed along positive v1 axis

sics_sias_coeff Relation

     This relation defines the coefficients that are used to transform data from between the Science
     Instrument Coordinate System (SICS) and the Science Aperture Coordinate System (SIAS).  The 
     command that primarily performs this transformation is PMDB/UPDATE, as transformations between 
     the V1-V2-V3, SICS, and SIAS are commonly required.
     
     The astrometry Pipeline SS_AST process uses this relation.


        Field name           type/size	 description  
        ----------           ---------   -----------
	coord_id             C10         This field specifies the aperture coordinate system ID.  It
	                                 is the ID of the aperture coordinate system used to specify
					 the location of the target within the aperture. It is the 
					 aperture id concatenated with the aperture coordinate system
					 id.  Defined in ST-ICD-26 part III appendix A.  Field 1 of 
					 the first aj record if assigned by IMTOOL.

        valid_date           C17         effective date (YYYY.DDD:HH:MM:SS) before which the data for
	                                 this aperture must not be used

        record_index         I2          This field is the index of the record for the aperture
                                         coord. ID. The max. value is 21 because of the max. poly. 
					 degree n (qaapol) is 5. These coeff. are subscripted jk 
					 (j = 0 to n, k = 0 to j) for a 5th degree poly. jk are
					 ordered as: 00, 10, 11, 20, 21, 22, 30, 31, 32, 33, 40, 41,
					 42, 43, 44, 50, 51, 52, 53, 54, and 55. This id is 1 for
                                         jk = 00, ... 21 for jk = 55. It is the record number of the
					 ak type record when assigned by IMTOOL

        x_sias_sics          R8          This field is the coefficient ajk for transforming the x 
	                                 coordinate from SIAS to SICS.  The value of jk is determined
					 by record_index. Field 1 of the ith ak record if assigned by
					 IMTOOL

        y_sias_sics          R8          This field is the coefficient bjk for transforming the y 
	                                 coordinate from SIAS to SICS.  The value of jk is determined
					 by record_index. Field 2 of the ith ak record if assigned by
					 IMTOOL

        x_sics_sias          R8          This field is the coefficient cjk for transforming the x 
	                                 coordinate from SICS to SIAS.  The value of jk is determined
					 by record_index.  Field 3 of the ith ak record if assigned by
					 IMTOOL

        y_sics_sias          R8          This field is the coefficient djk for transforming the y 
	                                 coordinate from SICS to SIAS.  It is the value of jk is 
					 determined by record_index. Field 4 of the ith ak record 
					 if assigned by IMTOOL

qtmchebychev Relation

     This relation contains piecewise chebychev polynomial approximations representing the ephemerides
     of moving targets.  The relation is an SPSS maintained relation with a lot of fields.  This
     relation is used by astrometry processing to get the position and velocity of the sun and moon
     at the astrometry observation time.

     The astrometry Pipeline FGSAST process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        the numerous fileds of this relation will not be specified here.  Links off of the SPSS web
	page can be followed to obtain detailed information for this relation.

executed Relation

     This relation provides a replacement for the "executed_flg" field in the "qobservation"
     relation since "qobservation" is replicated from SPSS and can not be updated by EDPS.
     Some additional fields are also supplied but only the "executed_flg" is updated by EDPS 
     software.  The additional fields can be used to distinguish dumps from science observations.

     The astrometry Pipeline FGSAST process updates the "executed_flg" field
     in this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        program_id           C3          When a proposal is accepted into the PMDB by SPSS it must
                                         be assigned a unique 3 character base 36 program identifier.
                                         This is done by the PMDB/ACCEPT_PROP command.  This program
                                         identifier is tagged as 'program_id' in most PMDB relations.
                                         Is is used for identification of proposals by spacecraft
                                         and OPUS software. It is also used in the OPUS and DADS
                                         rootname for all archived science data files.  Because of 
					 flight design software, program_id must be three characters."
        obset_id             C2          An observation set is a collection of one or more
                                         alignments that are grouped together based on FGS pointing
                                         requirements.  That is, if multiple alignments can all be
                                         executed using the same guide star pair, they are grouped
                                         into the same observation set.
                                         An observation set is identified by a 2 character base 36
                                         string.  This field,  typically called 'obset_id', will
                                         often contribute to the index on relation together with a
                                         proposal_id, version_num, and possibly other fields.
        ob_number            C2          For exposures, observations are numbered sequentially
                                         throughout an observation set and are assigned by 
                                         SMS/Gen. The connection between ob_number and the
                                         PMDB alignment and exposure ids is in the table qolink."
        proposal_id          C5          A proposal consists of many individual observations 
		                         submitted as a package by a proposer.  When a proposal is 
		                         processed by the proposal entry system (RPS2), 
		                         it is assigned a proposal identifier.  That identifier is 
		                         an integer that is converted into a 5 character base 36
		                         string.
        si_id                C4          This is the identifier type for a Science Instrument (SI).
		                         The SI list includes the following:
			                    FOC  - Faint Object Camera
			                    FOS  - Faint Object Spectrograph
			                    WFPC - Wide Field Planetary Camera 1
			                    WFII - Wide Field Planetary Camera 2
			                    WF3  - Wide Field Camera 3
			                    HRS  - High Resloution Spectrograph
			                    CSTR - COSTAR
			                    1    - Fine Guidance Sensor 1
			                    2    - Fine Guidance Sensor 2
			                    3    - Fine Guidance Sensor 3
			                    NIC  - NICMOS
			                    STIS - Space Telescope Infrared Spectrograph
                                            ACS  - Advanced Camera for Surveys
                                            COS  - Cosmic Origins Spectrometer"
        control_id           C5          This is information on how OPUS is supposed to
                                         process the data. The data is stored in five bytes:

                                            H/Y/N  : Calibration data flag
                                            F/P    : Output product type  (film/plot) - unused
                                            2 bytes: Output format spec               - unused
                                            Y/N    : Output product holding tank flag"
        coord_id             C10         This is the SI aperture and coordinate system
                                         identifier; it specifies the aperture and
                                         coordinate system of the instrument to be used for the 
					 observation of the target.  It is the aperture identifier
					 concatenated with the aperture coordinate system identifier.
                                         They specify the default location of the target within 
                                         the aperture.
        executed_flg         C1          When the record is created this value is blank. When
                                         the observation has been executed on board HST, OPUS
                                         receives a science POD file or EDPS generates an 
                                         astrometry file from engineering data, and this field is
                                         updated to the Type (ninth) character of the dataset
                                         rootname.

qbastr_archv Relation

     This relation provides information on archived Astrometry datasets.

     The astrometry Pipeline FGSAST process inserts records into this
     relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        program_id           C*3         A base 36 program id assigned to the proposal by pm 
	                                 when a proposal has been accepted.
        obset_id             C*2         The observation set id. these are numbered sequentially 
                                         throughout the proposal but may appear in only one 
					 scheduling unit.
        ob_number            C*2         The observation id. these are numbered sequentially 
                                         throughout the proposal but may appear in only one 
					 scheduling unit.
        astromy_file         C*9         The name given to describe a group of files.

        archdate             C*20        The latest file date associated with the dataset.

        window_start         C*11        Corrected spacecraft time for first minor frame in the 
	                                 file.  (UTC rounded to the nearest second, in the format
                                         YYDDDHHMMSS).
        window_stop          C*11        Corrected spacecraft time for last minor frame in the file.
	                                 (UTC rounded to the nearest second, in the format
                                         YYDDDHHMMSS).
        format_id            C*2         Telemetry format ID.

        perc_complet         I*2         Percentage of expected minor frames for the time interval
	                                 that were actually received.
        percent_bad          I*2         Percent of minor frames received with bad quality to minor
	                                 frames received.
        pdb_version          C*8         PDB tape ID number.

        environment          C*8         AEDP environment tape name.

        ast_success          C*2         Success of failure of extracting the astrometry observation,
                                         where: SS---success (5 total files)
                                                FF---Failure
        file_cnt             I*2         Information set file count when it becomes available for 
	                                 archiving.
        schdunit             C*23        Scheduling Unit name that was used to process the observation.  
	                                 It is of the form YYDDDHHMMSS_YYDDDHHMMSS for the start and
                                         stop times of the scheduling unit.  When scheduling units
					 become obselete with the replacement of the OMS system by
					 the EDPS system, this field will have the value "N/A".

dads_archive Relation

     This relation tracks requests made by applications to archive files and responses made by the on-line
     dads archive system.  Entries are retained in this table after processing is completed for historical
     purposes.

     The astrometry Pipeline ASTREQ and ASTRSP processes use 
     this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        dataset_name         C23         The name given to describe a group of files         

        archclass            C3          The classification used to archive the data 
 
        archdate             C20         The latest file date associated with the dataset    

        reqdate              C23         The date when the archive insertion request was generated    

        reqtype              C4          either a TAPE or DISK archive insertion requests   

        response             C10         Response status returned by DADS            

        disk_date            C23         The optical disk date assigned by DADS  

        file_cnt             I2          The file count as determined by DADS

        path                 C10         The path from which the request is made                    

        tape_date            C20         The date when a tape is made         

        saveset              C17         The saveset name

        archv_tape           C6          Tape label

qoarchives Relation

     This relation holds records that have been inserted when the OPUS data partitioning processes 
     determine the name of the ipppssoots from the science POD files.  Any pipeline process that
     subsequently has trouble processing science data will update the trouble_flag and trbl_process
     fields.  In addition, OPUS/EDPS archive processes update a number of fields in this relation.

     The astrometry Pipeline ASTREQ process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        program_id           C3          Unique 3 character base 36 program identifier for the proposal for
	                                 which this observation is a part.  Used with the obset_id, 
					 ob_number, and data_class fields to form the observation rootname,
					 which uniquely identifies an observation

       obset_id              C2          A collection of one or more alignments that are grouped together
                                         based on FGS pointing requirements.  That is, if multiple alignments
					 can all be executed using the same guide star pair, they are grouped
					 into the same observation set.  Part of the OPUS rootname.

       ob_number             C2          Observations are numbered sequentially throughout an observation set 
                                         and are assigned by sms (base 36 number max. 1295 observations per
					 obset).  Part of the OPUS rootname.

       data_class            C1          Type of data (R real-time, T tape-recorded, etc

       obs_root              C9          The ipppssoot, where
                        
                                              i = instrument code (N - NICMOS, O - STIS, U - WFPC2
                                                  V - HSP, W - WFPC1, X - FOC, Y - FOS, Z - HRS)
                                            ppp = program_id
                                            ss  = obset_id
                                            oo  = ob_number
                                            t   = data_clas

       proc_strt_tm          C16         Time pipeline processing for this dataset.  Format is 
                                         yyyydddHHMMSSsss

       proc_stop_tm          C16         Time pipeline processing completed for this dataset. Format is 
                                         yyyydddHHMMSSsss   

       data_eval             I4          obsolete field??

       flg_mismatch          C1          archive flag for file count mismatches

       geis_only             C1          obsolete field??

       calib_indic           I2          obsolete field??

       trouble_flag          C1          Set to 'T' if observation sent to 'trouble'

       trbl_process          C6          Name of process that sent observation to 'trouble'   

       edsci_file            C9          obsolete field??

       edt_archdate          C20         DADS ARCHDATE for EDT archive class.  Format is yyyydddHHMMSSss

       edt_fcnt              I2          File count for EDT archive class

       calib_file            C9          obsolete field??

       cal_archdate          C20         DADS ARCHDATE for CAL archive class.  Format is yyyydddHHMMSSsss         

       cal_fcnt              I2          File count for CAL archive class

       cdbs_data             C15         obsolete field??
           
       repro_flg             C10         obselete field??

archive_files Relation

     This relation is used to track a dataset's file extensions. The file extension are written to 
     this relation when the ARCHIVE_CLASS.TRACK_EXT is set to "Y" in a processes resource file.

     The astrometry Pipeline ASTREQ process uses this relation.


       	Field name           type/size	 description  
        ----------           ---------   -----------
        dataset_name         C23         The name given to describe a group of files

        archclass            C3          The classification used to archive the data          

        archdate             C20         The latest file date associated with a dataset           

        file_ext             C3          The files' extension

Database Querries Performed

RAHOLD Process Querries

RAWAST Process Querries

ASTKWD Process Querries

SS_AST Process Querries

FGSAST Process Querries

ASTREQ Process Querries

ASTRSP Process Querries

ASTFIN Process Querries