PDS_VERSION_ID = PDS3
RECORD_TYPE = STREAM
DATA_SET_ID = "RO-C-RSI-1/2/3-ESC2-0669-V1.0"
PRODUCT_ID = "OPTG_SIS"
PRODUCT_CREATION_TIME = 2017-07-24T17:32:44.000
OBJECT = TEXT
PUBLICATION_DATE = 1996-02-28
NOTE = "Software Interface Specification for the Orbit
Propagation and Timing Geometry (OPTG) File"
END_OBJECT = TEXT
END
Table of Contents
* 1. General Description
o 1.1 Purpose of Interface
o 1.2 Scope
o 1.3 Applicable Documents
o 1.4 Functional Description
+ 1.4.1 Data Source, Destination, and Transfer Method
+ 1.4.2 Pertinent Relationships with Other Interfaces
+ 1.4.3 Labeling and Identification
+ 1.4.4 Assumptions and Constraints
* 2. Environment
o 2.1 Hardware Characteristics and Limitations
o 2.2 Interface Medium and Characteristics
o 2.3 Input/Output Protocols
+ 2.3.1 Device Addressing
+ 2.3.2 Operating System Protocols
+ 2.3.3 Deformatting
+ 2.3.4 Calling Sequence
o 2.4 Failure Protection, Detection, and Recovery Features
+ 2.4.1 Backup Requirements
+ 2.4.2 Security/Integrity Measures
o 2.5 End-of-File (or Medium) Conventions
o 2.6 Utility Programs
* 3. Data Flow Characteristics
o 3.1 Operational Characteristics
+ 3.1.1 Generation Method and Frequency
+ 3.1.2 Time Span of Product
o 3.2 Data Volume
o 3.3 Flow Rate
* 4. Detailed Data Object Definition
o 4.1 Structure and Organization Overview
o 4.2 Data Format and Definition
+ 4.2.1 SFDU Data Description
+ 4.2.2 Non-SFDU Data Description
+ 4.2.2.1 Header Records
+ 4.2.2.2 Data Records
+ 4.2.2.3 Last File Record
* Appendix A. Acronyms
1. GENERAL DESCRIPTION
1.1 PURPOSE OF INTERFACE
This Software Interface Specification (SIS) describes the content of the
Orbit Propagation and Timing Geometry File (OPTG). It is intended that this
interface will satisfy requirements for the Mars Global Surveyor (MGS) and
Cassini missions.
1.2 SCOPE
The format and syntax specifications in this SIS applies to all phases of
the mission.
1.3 APPLICABLE DOCUMENTS
699-FSO/NAV-FRD-501 Cassini Functional Requirements
and Design Document
SFOC0038-01-09-01 10 Jan 94 SFOC-1-CDB-ANY-CATALOG2
SFOC0099-04-00 20 Nov 92 Data Dictionary, Rev C
SFOC0038-00-08-01 26 Feb 88 SFOC-1-CDB-MGN-TIMESFILE
SFOC0038-01-09-03 30 Aug 94 SFOC-2-SYS-ANY-TIMEFORMS
1 Oct 94 DPTRAJ-ODP User Reference Manual,
SOM Vol. 1 and Vol. 2
1 Oct 94 DPTRAJ and ODP Interfaces and
File Format Descriptions,
SOM, Vol. 3
1.4 FUNCTIONAL DESCRIPTION
The OPTG file contains data for many trajectory and/or geometry
events relative to the spacecraft, e.g., periapsis and apoapsis
passage times for an orbiter, Earth and Sun occultation times,
inferior and superior conjunction times, and many other events.
1.4.1 Data Source, Destinations, and Transfer Method
OPTG data shall be created by the DPTRAJ program TWIST running
on the NAV computer system. The destination of this file is the
Central Data Base (CDB). The transfer medium is via the
MGSO network.
1.4.2 Pertinent Relationships with Other Interfaces
The generation of this file is dependent upon the spacecraft
ephemeris file availability spanning the time over which the
OPTG file is desired.
1.4.3 Labeling and Identification
Internal labeling of the OPTG file is accomplished with header
records as defined in Section 4.2.
1.4.4 Assumptions and Constraints
None.
2. ENVIRONMENT
2.1 HARDWARE CHARACTERISTICS AND LIMITATIONS
Execution of the software to generate the OPTG file shall be
on the NAV computer.
2.2 INTERFACE MEDIUM AND CHARACTERISTICS
NAV computer catalogued file shall use the MGSO project LAN
as the medium for transmittal to the CDB.
2.3 INPUT/OUTPUT PROTOCOLS
None.
2.3.1 Device Addressing
N/A
2.3.2 Operating System Protocols
N/A
2.3.3 Deformatting
Users of the OPTG file will be required to have software to
remove the SFDU data from the CDB stored file.
2.3.4 Calling Sequence
N/A
2.4 FAILURE PROTECTION, DETECTION, RECOVERY FEATURES
2.4.1 Backup Requirements
The Navigation Subsystem shall keep the Orbit Propagation and
Timing Geometry File in the NAV computer until it is confirmed
as stored within the CDB. Backups will be maintained through
normal archiving procedures of the CDB.
Should the CDB malfunction or the network fail, customers of
the OPTG File may obtain the file via the secondary method
which is to receive the data in TBD form from the
NAV Subsystem.
2.4.2 Security/Integrity Measures
The CDB security/integrity measures will be in effect.
2.5 END-OF-FILE (OR MEDIUM) CONVENTIONS
The end-of-file is marked with an $$EOF record.
2.6 UTILITY PROGRAMS
Utility programs developed by MGSO shall be used to
insert and remove SFDU labels from the OPTG file.
3. DATA FLOW CHARACTERISTICS
3.1 OPERATIONAL CHARACTERISTICS
3.1.1 Generation Method and Frequency
The OPTG data shall be created by NAV DPTRAJ program TWIST.
The file shall be generated at a frequency consistent with
project requirements.
3.1.2 Time Span of Product
The time span of the file is controlled by the span of the
spacecraft ephemeris input to TWIST and by user input.
3.2 DATA VOLUME
The size of the file depends on the length of the trajectory
and the number of event triggers (TWIST input) encountered
per orbit.
3.3 FLOW RATE
Determined by the LAN traffic.
4. DETAILED DATA OBJECT DEFINITION
4.1 STRUCTURE AND ORGANIZATION OVERVIEW
The OPTG file is an ASCII file which consists of the SFDU header,
the OPTG headers, and the OPTG data. Each will be described in
the following sections.
4.2 DATA FORMAT AND DEFINITION
4.2.1 SFDU Data Description
The SFDU information and structure, for the OPTG file, is illustrated in
the following example:
CCSD3ZS00001AAAAAAAA
NJPL3KS0L015BBBBBBBB
<CR><LF>
MISSION_NAME=***;<CR><LF>
SPACECRAFT_NAME=***;<CR><LF>
DATA_SET_ID= "RO-C-RSI-1/2/3-ESC2-0669-V1.0"
FILE_NAME=optg.sff;<CR><LF>
PRODUCER_ID=NAV;<CR><LF>
APPLICABLE_START_TIME=1994-04-04T07:00:00.000;<CR><LF>
APPLICABLE_STOP_TIME=1994-04-04T15:00:00.000;<CR><LF>
PRODUCT_CREATION_TIME= 2017-07-24T17:32:44.000
CCSD3RE00000BBBBBBBB
NJPL3IS0nnnnCCCCCCCC
<CR><LF>
In the above *** will be MARS-GLOBAL-SURVEYOR or CASSINI
depending on whether the mission is MGS or CASSINI.
nnnn, the DDID, will be 0357 for MGS and 0380 for CASSINI.
In the actual OPTG File, the following SFDU data is located at the end of
the file, following the non-SFDU data which is described in Section 4.2.2.
CCSD3RE00000CCCCCCCC
CCSD3RE00000AAAAAAAA
4.2.2 Non-SFDU Data Description
The non-SFDU portion of the OPTG file contains data described in Sections
4.2.2.1 and 4.2.2.2 as follows:
4.2.2.1 Header Records
Header RECORD 1 - Identifies file type and version/delimits start
of header.
Column Content Description
---------------------------------------------------------------------
01-02 "$$" Control characters signifying major
control card.
03-06 "XXXX" Key Word - identifies the mission for
this file, e.g. CAS for Cassini, or
MGS for Mars Global Surveyor. Left
justified.
14-55 "ORBIT PROPAGATION Identifies the file
AND TIMING GEOMETRY
FILE"
57-60 "vnnn" Identifies the file version, eg
v001.
Header RECORD 2 - Identifies file name.
Column Content Description
------------------------------------------------------------------
01-01 "*" Header character
03-06 "OPTG" Key Word - identifies record type.
14-72 File name File name retrieved from the
Fortran 77 execution of the
INQUIRE statement. Could be, for
example, OPTG_TEST.TXT
Header RECORD 3 - Specifies the title of the OPTG file.
Column Content Description
--------------------------------------------------------------------
01-01 "*" Header character
03-07 "TITLE" Key Word - identifies record type.
14-72 Title Any alphanumeric expression up to 59
characters, input by the user via
the GIN file to NAV program TWIST
that generates OPTG file. This could
be used to identify the purpose of
the OPTG file being generated. For
example, this could be text that
says, "This is a test OPTG file for
the cruise phase."
Header RECORD 4 - Specifies JPL local file creation time.
Column Content Description
----------------------------------------------------------------------
01-01 "*" Header character
03-10 "CREATION" Key Word - identifies date and time
when OPTG file was created.
14-16 "JPL" Defines time base.
18-35 "YY-MMM-DD/hh:mm:ss" Date and time in local time format.
For example, 88-DEC-18/14:32:45.
Header RECORD 5 - Specifies SCE start time of file coverage.
Column Content Description
---------------------------------------------------------------------
01-01 "*" Header character
03-07 "BEGIN" Key Word - identifies record type.
14-16 "SCE" Defines time base.
18-39 "YY-MMM-DD/hh:mm:ss.fff" S/C event time (ephemeris time) when
the OPTG file is to begin. For
example, 88-DEC-18/14:32:45.050.
Header RECORD 6 - Specifies SCE cutoff time of file coverage.
Column Content Description
--------------------------------------------------------------------
01-01 "*" Header character
03-08 "CUTOFF" Key Word - identifies record type.
14-16 "SCE" Defines time base.
18-39 "YY-MMM-DD/hh:mm:ss.fff" S/C event time (ephemeris time) when
the OPTG file is to end.
Header RECORD 7 - Specifies trajectory data base for run.
Column Content Description
----------------------------------------------------------------------
01-01 "*" Header character
03-07 "PFILE" Key Word - identifies record type.
14-16 "JPL" Defines time base.
18-35 "YY-MMM-DD/hh:mm:ss" The creation date and time of the
PFILE used to make the OPTG file. For
example, 88-DEC-18/14:32:45.
Header RECORD 8 - Specifies program that created PFILE.
Column Content Description
------------------------------------------------------------------
01-01 "*" Header character
03-09 "PVDRIVE" Name of the program that generated
or "PDRIVE" the PFILE used by TWIST to create
or "SEPV" the OPTG file.
14-16 "JPL" Defines time base.
18-35 "YY-MMM-DD/hh:mm:ss" Creation date and time of the
program that wrote the PFILE.
Header RECORD 9 - Specifies run which produced OPTG file.
Column Content Description
---------------------------------------------------------------------
01-01 "*" Header character
03-07 "TWIST" Key Word - identifies program used to
generate the OPTG file.
14-16 "JPL" Defines time base.
18-35 "YY-MMM-DD/hh:mm:ss" The creation date and time of the
version of the program that wrote
the OPTG file.
Header RECORD 10 - Specifies the phase of the mission.
Column Content Description
---------------------------------------------------------------------
01-01 "*" Header character
03-17 "CRUISE", Mission phase is either cruise, orbit
"ORBIT INSERTION" insertion, or mapping.
or
"MAPPING"
Header RECORD 11
Record specifying the event signifying the start of a new orbit.
Column Content Description
----------------------------------------------------------------------
01-01 "*" Header character
03-16 "ORBIT BOUNDARY" Key Word - identifies record type.
20-25 One of the event Name of the event that will signify
titles from, the the start of a new orbit, input to
orbit insertion or TWIST. Valid event names for this
mapping phases purpose are: "PERIAP", "AEQUAX",
"DEQUAX", "APOAP",. However, once an
event is chosen for the orbit
boundary, it should not be changed
during the entire phase.
28-33 A right justified Initial orbit number input by the
integer user to TWIST.
LAST Header RECORD - Delimits end of header/start of data records.
Column Content Description
--------------------------------------------------------------------
01-02 "$$" Characters signifying major control
card.
03-05 "EOH" Key Word - identifies end of header
records.
4.2.2.2 Data Records
Data records correspond to geometric events occurring during the various
phases; where the first record for an event contains the event type, and
subsequent records contain the event body, the epoch, the orbit number, the
time from periapsis, and the SEP angle. For some of the events, additional
information is included as indicated.
DATA RECORD n
Column Content Description
--------------------------------------------------------------------
01-06 Event title Alphanumeric expression title,
(<=6 characters left justitied)
describing event.
Possible events for cruise, orbit
insertion and mapping are:
"START " Start of coverage,
"CONST " Body constants,
"SCONB " Begin superior conjunction,
"SCONE " End superior conjunction,
"ICONB " Begin inferior conjunction,
"ICONE " End inferior conjunction,
"SCONJ " Given Sun-Earth-probe angle
during superior conjunction,
"ICONJ " Given Sun-Earth-probe angle
during inferior conjunction,
"ICONM " Inferior conjunction minimum
Sun-Earth-probe angle,
"SCONM " Superior conjunction minimum
Sun-Earth-probe angle,
"PERIAP" Closest approach,
"EOCCAB " Begin geocentric atmospheric
occultation,
"EOCCAE " End geocentric atmospheric
occultation,
"SOCCAB " Begin heliocentric
atmospheric occultation,
"SOCCAE " End heliocentric atmospheric
occultation.
"EOCCSB" Begin geocentric surface
occultation,
"EOCCSE" End geocentric surface
occultation,
"SOCCSB" Begin heliocentric surface
occultation,
"SOCCSE" End heliocentric surface
occultation.
Additional possible events for
mapping and orbit insertion are:
"APOAP " Apoapsis passage,
"AEQUAX" Ascending equator crossing,
"DEQUAX" Descending equator crossing,
"DLTERM" Dark-light terminator
crossing,
"LDTERM" Light-dark terminator
crossing,
"NPOLEX" North polar minimum slant
range crossing,
"SPOLEX" South polar minimum slant
range crossing.
07-07 "," Separator
09-14 Name Name of the body/object associated
with the event named.
15-15 "," Separator
17-37 Date and time to SCE ET* time in format
millisecond precision YYYY-DDDThh:mm:ss.fff. For example,
1988-352T14:32:45.981 represents
December 18, 1988 at 14 hours, 32
minutes, 45.981 seconds.
38-38 "," Separator
40-63 Julian date Double precision Julian date
representation of the SCE /time.
64-64 "," Separator
66-71 ET-UTC to millisecond Difference between ephemeris time
precision and broadcast universal time in
format ss.fff.
72-72 "," Separator
74-79 Current orbit number Integer
80-80 "," Separator
* ET implies ephemeris time. In all data records ephemeris
time will be used for spacecraft event time.
DATA RECORD n + 1
Column Content Description
--------------------------------------------------------------------
02-20 Time from periapsis Time from periapsis in the form
to millisecond + or -DDDDDThh:mm:ss.fff
precision
21-21 "," Separator
23-46 Sun-Earth-probe angle Double precision Sun-Earth-probe
in degrees angle. Range (0 deg [Image]
SEP [Image] 180 deg).
47-47 "," Separator
The following extra data records contain body constants
(Event = CONST):
DATA RECORD CONST
Column Content Description
--------------------------------------------------------------------
02-25 Base epoch Double precision seconds past
J2000.0 defining the base time, t
for the rotation angle polynomials.
26-26 "," Separator
DATA RECORD + 1 CONST
Column Content Description
--------------------------------------------------------------------
02-25 Constant term (deg) Double precision number specifying
the constant term for pole right
ascension.
26-26 "," Separator
28-51 Linear term Double precision number specifying
(deg/(Jul cen)) the linear term for pole right
ascension.
52-52 "," Separator
DATA RECORD + 2 CONST
Column Content Description
--------------------------------------------------------------------
02-25 Constant term (deg) Double precision number specifying
the constant term for pole
declination.
26-26 "," Separator
28-51 Linear term Double precision number specifying
(deg/(Jul cen)) the linear term for pole
declination.
52-52 "," Separator
DATA RECORD + 3 CONST
Column Content Description
--------------------------------------------------------------------
02-25 Constant term (deg) Double precision number specifying
the constant term for the angle W.
26-26 "," Separator
28-51 Linear term Double precision number specifying
(deg/day) the linear term for the angle W.
52-52 "," Separator
DATA RECORD + 4 CONST
Column Content Description
--------------------------------------------------------------------
02-25 Surface radius Double precision number that
(km) measures equatorial surface radius.
Range 0.
26-26 "," Separator
28-51 Surface occultation Double precision number that
radius (km) measures equatorial surface
radius for occultations. Range 0.
52-52 "," Separator
54-77 Atmospheric radius Double precision number that
(km) measures the atmospheric radius at
the equator. Range 0.
78-78 "," Separator
DATA RECORD + 5 CONST
Column Content Description
--------------------------------------------------------------------
02-25 Flattening factor Double precision number defining
the flatness. Range (0 f < 1).
26-26 "," Separator
The following extra records are included at the start of coverage
(EVENT = START):
DATA RECORD START
Column Content Description
--------------------------------------------------------------------
02-07 Body name Name of the reference body for the
spacecraft state coordinates
08-08 "," Separator
10-16 Coordinate system Defines the coordinate system for the
label spacecraft state coordinates:
"EMO2000" means Earth mean orbit and
equinox of J2000.0.
17-17 "," Separator
DATA RECORD + 1 START
Column Content Description
--------------------------------------------------------------------
02-25 Semimajor axis (km) Double precision number giving the
semimajor axis of the spacecraft
orbit.
26-26 "," Separator
28-51 Orbit eccentricity Double precision number giving
the eccentricity of the
spacecraft orbit. Range 0.
52-52 "," Separator
DATA RECORD + 2 START
Column Content Description
--------------------------------------------------------------------
02-25 Orbit inclination Double precision number giving the
(deg) inclination of the spacecraft orbit.
Range (0 deg i 180 deg).
26-26 "," Separator
28-51 Ascending node angle Double precision number giving the
(deg) longitude of the ascending node of
the spacecraft orbit.
Range (0 deg < 360 deg).
52-52 "," Separator
54-77 Argument of Double precision number giving the
periapsis (deg) argument of periapsis.
Range (0 deg < 360 deg).
78-78 "," Separator
The following extra data record is present if the event is an
ascending equator crossing (Event = AEQUAX):
DATA RECORD AEQUAX
Column Content Description
--------------------------------------------------------------------
02-25 Longitude (deg) Double precision real number that is
a measure of the longitude of the
spacecraft. Range (0 deg < 360 deg).
26-26 "," Separator
The following extra data record is present if the event is an
descending equator crossing (Event = DEQUAX):
DATA RECORD DEQUAX
Column Content Description
--------------------------------------------------------------------
02-25 Longitude (deg) Double precision real number that is
a measure of the longitude of the
spacecraft. Range (0 deg < 360 deg).
26-26 "," Separator
28-35 Local solar time to Local mean solar time at the
the second spacecraft in the form
hh:mm:ss.
36-36 "," Separator
The following extra data record is present if the event is an
entry or exit from geocentric occultation (Event = EOCCAB, EOCCAE
EOCCSB, or EOCCSE):
DATA RECORD OCCULT
Column Content Description
--------------------------------------------------------------------
02-25 Longitude (deg) Double precision real number that is
a measure of the longitude of the
spacecraft. Range (0 deg < 360 deg).
26-26 "," Separator
28-51 Latitude (deg) Double precision real number that is
a measure of the latitude of the
spacecraft relative to the occulting
body. Range (-90 deg 90 deg).
52-52 "," Separator
The following extra data records are present at all apoapsis and
periapsis events (Event = APOAP or PERIAP):
DATA RECORD PERIAP/APOAP
Column Content Description
--------------------------------------------------------------------
02-25 Semimajor axis (km) Double precision number giving the
semimajor axis of the spacecraft
orbit relative to the event body
centered coordinate system.
26-26 "," Separator
28-51 Orbit eccentricity Double precision number giving the
eccentricity of the spacecraft orbit.
Range 0.
52-52 "," Separator
54-77 True anomaly (deg) Double precision number giving the
true anomaly of the spacecraft.
Range (-180 deg < 180 deg).
78-78 "," Separator
DATA RECORD + 1 PERIAP/APOAP
Column Content Description
--------------------------------------------------------------------
02-25 Orbit inclination Double precision number giving the
(deg) inclination of the spacecraft orbit
relative to the event body centered
EME2000* coordinate system.
Range (0 deg i 180 deg).
26-26 "," Separator
28-51 Ascending node angle Double precision number giving the
(deg) longitude of the ascending node of
the spacecraft orbit relative to the
event body centered EME2000*
coordinate system.
Range (0 deg < 360 deg).
52-52 "," Separator
54-77 Argument of Double precision number giving the
periapsis (deg) argument of periapsis relative to
the event body centered EME2000*
coordinate system.
Range (0 deg < 360 deg).
78-78 "," Separator
*EME2000 refers to the Earth Mean Equatorial J2000 reference system.
DATA RECORD + 2 PERIAP/APOAP
Column Content Description
--------------------------------------------------------------------
02-25 Orbit inclination Double precision number giving the
(deg) inclination of the spacecraft orbit
relative to the event body centered
equatorial coordinate system.
Range (0 deg i 180 deg).
26-26 "," Separator
28-51 Ascending node angle Double precision number giving the
(deg) longitude of the ascending node of
the spacecraft orbit relative to the
event body centered equatorial
coordinate system.
Range (0 deg < 360 deg).
52-52 "," Separator
54-77 Argument of Double precision number giving the
periapsis (deg) argument of periapsis relative to
the event body centered equatorial
coordinate system.
Range (0 deg < 360 deg).
78-78 "," Separator
DATA RECORD + 3 PERIAP/APOAP
Column Content Description
-------------------------------------------------------------------
02-25 Body-Earth range (km) Double precision range from the
event body to the Earth. Range 0.
26-26 "," Separator
28-51 Altitude (km) Double precision spacecraft
altitude relative to the event body.
52-52 "," Separator
The following additional records are present in the case of a
periapsis (Event = PERIAP):
DATA RECORD PERIAP
Column Content Description
------------------------------------------------------------------
02-25 Sun sigma angle (deg) Double precision real number that
is a measure of the angle along
the spacecraft orbit plane from
the periapsis direction to the
body-Sun direction.
Range (0 deg < 360 deg).
26-26 "," Separator
28-51 Sun beta angle (deg) Double precision real number that
is a measure of the angle from the
spacecraft orbit plane normal
vector to the body-Sun direction
vector. Range (0 deg 180 deg).
52-52 "," Separator
DATA RECORD + 1 PERIAP
Column Content Description
------------------------------------------------------------------
02-25 Dynamic pressure Double precision real number that
(N/m2) measures the dynamic pressure on
the spacecraft. Range 0.
26-26 "," Separator
28-51 Atmospheric density Double precision real number that
(kg/m3) measures the atmospheric density
at the spacecraft. Range 0.
52-52 "," Separator
DATA RECORD + 2 PERIAP
Column Content Description
------------------------------------------------------------------
02-25 Drag pass duration Double precision real number that
(sec) measures the duration* of the
current drag pass. Range 0.
26-26 "," Separator
28-51 Freestream heatflux Freestream heatflux at the
(W/cm2) spacecraft. Range 0.
52-52 "," Separator
* As the spacecraft is entering the atmosphere, the dynamic
pressure increases. When the dynamic pressure equals or
exceeds .0015 n/m**2 (>=.0015), the drag interval begins.
As the spacecraft is exiting the atmosphere, the dynamic pressure
decreases. When the pressure is less than .0015 n/m**2 (<.0015),
the drag interval ends. The drag interval is computed from the
entry and exit times and is represented in seconds. If the
spacecraft is located such that the dynamic pressure is always
less than .0015 n/m**2, the drag duration will be zero (0).
If the dynamic pressure is always greater than or equal to
.0015 n/m**2 the drag duration will be set to the orbital period.
DATA RECORD + 3 PERIAP
Column Content Description
------------------------------------------------------------------
02-25 Reference altitude Double precision real number that
(km) specifies the reference altitude.
26-26 "," Separator
28-51 Atmospheric density Double precision real number that
(kg/m3) measures the atmospheric density
at the reference altitude.
Range 0.
52-52 "," Separator
The following extra data record is present when the event is a
north or south polar crossing (Event = NPOLEX or SPOLEX):
DATA RECORD NPOLEX/SPOLEX
Column Content Description
-------------------------------------------------------------------
02-25 Slant range (km) Double precision real number that
gives the distance between the
spacecraft and the north/south
pole. Range 0.
26-26 "," Separator
4.2.2.3 Last File Record
This record signifies the "end of file".
Column Content Description
------------------------------------------------------------------
1-2 "$$" Control characters signifying
major control card.
3-5 "EOF" Key Word - identifies the end of a
file.
Appendix A. ACRONYMS
ASCII American Standard Code for Information Interchange
MOPS Maneuver Operations Program Set
NAV Navigation
SIS Software Interface Specification
To OPTG SIS
To Navigation Software Documentation
To Navigation Software
Revision date: 3 February 1997
For information about this on-line document, contact Vic Legerton
For information about the file described by this document, contact John
Ekelund