Ephemerides and AHF
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FreeFlyer can use the data contained in ephemeris files to seed an initial Spacecraft state, and then use an integrator and Force Model to "Step" the Spacecraft forward in time, or FreeFlyer can step the Spacecraft sequentially to the states represented by the data points in the ephemeris file, interpolating Spacecraft states in between data points if desired. See the Importing an Ephemeris File page for more information on stepping the Spacecraft using an ephemeris file.
FreeFlyer can write ephemeris data to an external file in several formats. For more information on writing ephemeris data to a file, see the Ephemeris Formats table below, the Creating an Ephemeris File page, and the Put command page of the Help file.
FreeFlyer can both read and write:
The FreeFlyer ephemeris file is an ephemeris-file format native to FreeFlyer which can contain orbit-only, attitude-only or attitude and orbit data. Later versions of that format also support user-defined columns, user-defined delimiters, adding discontinuities, setting interpolation methods for columns, and setting comments for ephemeris vectors. In addition, FreeFlyer also supports several other ephemeris and attitude history file formats, as shown below.
See the Creating an Ephemeris File page and the Put command for information on creating an ephemeris file from the Ephemeris Object.