Satellite Properties

SPICE Propagator

Use the SPICE (Spacecraft, Planet, Instrument, C-matrix--spacecraft attitude--, and Events) propagator to access ephemeris files created with the SPICE toolkit, maintained by the Jet Propulsion Laboratory (JPL).

To use an external SPICE file to propagate a vehicle:

  1. Select the SPICE Propagator.
  2. Type the file path and name of the external ephemeris file in the text box to the right of the Spice Filename field, or use the button to browse for a file.
  3. Choose a satellite ID, Start Time, Stop Time & Step Size.
  4. Click Apply to load the SPICE file and use it when ephemeris data is requested for the satellite.

The start and stop times must be within the ephemeris window contained in the file (you can use the slider to traverse through the different ephemeris segments for the satellite contained in the SPICE file).

  • There is no ephemeris prior to 2000 available for Jupiter and its moons.
  • STK is able to read a SPICE file whenever the SPICE toolkit is able to generate ephemeris from that file for at least one central body known to STK.
  • SPICE files are loaded only when STK is started. The files cannot be changed and reloaded without starting STK.
  • For more information on how SPICE files are automatically loaded by STK, click here.