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Cosmographia is a SPICE-based visualizer for planet ephemerides and solar system missions maintained by NAIF/SPICE at JPL and available here: https://naif.jpl.nasa.gov/naif/cosmographia.html

In a (not entirely) interactive context, Cosmographia can be used to visualize trajectories provided as SPICE kernels by some services, e. g., the DynAstVO computation system for Near-Earth Objects in Paris.

DynAstVO produces files such as .bsp (SPICE SPK ephemeris) and .json (both to be integrated in the EPN-TAP data service) for each body of interest. These files can be used in Cosmographia to plot trajectories computed in DynAstVO. The example below uses the reconstructed orbit of 2017AG13, an Earth-grazer asteroid early in 2017.

    •    Create a dedicated directory with object name (2017AG13) in Cosmographia root directory and move json (2017AG13-spice.json) & bsp (DAV_2017AG13.bsp) files inside.

    •    The json file is a configuration file for Cosmographia. In this particular case, the 2017AG13-spice.json is directly usable.

    •    For other objects, you have to edit it and change fields "name", "spiceKernels", and "target" (inside "trajectory") - the latter is the spk ID provided in DynAstVO (parameter id_spk, here = 532900332)

    •    Below line "bodyFrame": "EquatorJ2000" everything is optional and concerns rotation parameters and size (should be straightforward). A shape model is introduced by "source" (511davida.cmod) while size is provided in km (2017AG13 is 24m large, hence size = 0.024).

    •    Whenever no shape model is included, the body will appear as a point in Cosmographia! So mention a dummy one if none is available.

Then launch Cosmographia, click File>Open Catalog and select the 2017AG13 json file. This particular object should appear inside the Moon's orbit in January 2017.


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