This attribute defaults and resets options for satellite ephemerides output by the Satellite, Simulator, Filter, VLS, and Smoother objects.


This control defaults and resets the coordinate frame selection for satellite ephemerides output by the Satellite, Simulator, Filter, VLS, and Smoother objects. This control is a fixed set with one default coordinate frame setting for each Central Body choice. This parameter is used to default the Satellite.EphemerisGeneration.CoordFrame attribute as well as the *. Output.STKEphemeris.DuringProcess.CoordFrame controls for * = Simulator, Filter, VLS, and Filter. (see note following the next table).

CoordFrame Attribute Settings
Parameter Description
CBName Central Body name associated with this coordinate frame selection (may be "Earth", "Moon", "Sun"). A read only parameter.
CoordFrame Coordinate frame to be used for a spacecraft with initial conditions referenced to the associated central body. For Earth, choose between ICRF, J2000, TEMEofDate or Fixed. For Sun, choose between ICRF, J2000, or Fixed. For satellites with initial conditions referenced to the Moon, choose between ICRF, J2000, Fixed, Mean Earth, and Inertial.

Note: When the CoordFrame is applied in the GUI not only will new object ephemeris output coordinate frames be defaulted to these settings, but ephemeris output coordinate frame settings for existing objects will also be reset. If the CoordFrame control is changed through scripting, e.g.

        Set frame = ODTK.Scenario(0).SatEphemeris.CoordFrame(0).CoordFrame
        Frame .CoordFrame = "Fixed"
then existing object coordinate frame settings will not be reset. However, they can be reset using the scenario SetEphCoordFrame attribute function, e.g.
        set bRet = SetEphCoordFrame ("Earth", "Fixed")


Parameters to support writing of CCSDS 502 ephemeris message file format (*.oem).

Reference Consultative Committee for Space Data Systems (CCSDS) Orbit Data Messages, CCSDS 502.0-B-1. Note that ODTK currently supports OEM version 2 optional covariance, but not optional acceleration.

CCSDS Attribute Settings
Parameter Description
Originator Message Originator string identifier. Defaulted to "ODTK". When the default is used the "ORIGINATOR" keyword will be set to the ODTK process that generated the message.
DateFormat ISO/CCSDS ASCII date format.
  • YMD = day of month format, e.g. 2009-12-18T14:28:15.1172
  • YDOY= day of year format, e.g. 2009-277T07:22:54
TimePrecision The number of "seconds" decimal digits to the right of the decimal point (0-10)/
EphemerisFormat Format for position/velocity output.
  • SciNotation = Scientific Notation
  • FloatingPoint = FloatingPoint
OutputVersion OEM version identifier when writing a CCSDS OEM file. May be 1.0 or 2.0. Files designated 1.0 will not include any Covariance data (even if requested by the object’s Output.STKEphemeris properties). Note this parameter is not used when reading an OEM file; in this case the version number in the file is used.

ODTK 6.5