What is a SPICE file? A SPICE
(Spacecraft, Planet, Instrument, C-matrix--spacecraft attitude--, and Events) file contains binary data that defines the position and velocity of one or more celestial objects over large spans of time. A SPICE file can be used to represent artificial satellites, planetary bodies, moons, comets, and asteroids. A detailed description of SPICE files can be found on the NASA website. SPICE files for SatellitesSPICE files can be read directly into STK as a satellite object propagator, as described in the STK Desktop help, here. Ephemeris files for many interplanetary spacecraft are archived and continually updated in SPICE format. There are a few repositories for this data, such as the NASA Navigation and Ancillary Information Facility and the ESA Planetary Science Archive. You can download these files directly from these websites and use them in STK. For more information about how load these satellites, refer to the AGI FAQ article, Is there a satellite database for interplanetary spacecraft?Additional Resources for Satellites using SPICE
For information about automatically creating STK objects from all bodies defined in a SPICE file, using a MATLAB script, refer to the AGI resource page, Automatic Loading of SPICE files as Satellites. The script (available for download from the page) makes it easy to load one SPICE file that includes multiple bodies and multiple segments. It automates loading a SPICE file by using a function called PropSpice(‘File location’). SPICE files for Central BodiesBy default, the ephemerides for most central bodies in STK are obtained from a Developmental Ephemeris (DE) file; such files contain tables of position and velocity over a large span of time. For more information, refer to the STK Desktop help topic, Technical Notes for Central Bodies - Configuration Settings, Shapes, Ephemerides, and Coordinate Systems. The DE ephemeris includes all of the planets and most of the larger moons, but central body ephemeris can also be taken from SPICE files from the JPL. If you have additional Central Body information in SPICE format, you can refer to the AGI FAQ article, Create central bodies using SPICE files. Additional Resources for Central Bodies using SPICEEphemerides for planetary moons that are not already modeled in STK, in SPICE format, are archived and continually updated at the NASA Navigation and Ancillary Information Facility. For more information, refer to the AGI FAQ article, How do I obtain STK-compatible ephemeris for planetary moons that are not already modeled in STK?The NASA JPL website, Horizons, allows you to build STK-compatible SPICE files for comets, asteroids, and other small bodies. For instructions on this process, refer to the AGI FAQ article, How can I obtain STK-compatible ephemeris files for comets, asteroids, and other small bodies?