There are 4 elements (also labeled on a screenshots) you have to download in order to run the simulation:
- Cosmographia itself
- Zipped package – these are the JSON definition files that Cosmographia uses to know what is inside of the SPICE kernels
- SPICE Kernels – files that contain data describing the entire mission
First two are available on ESA’s Cosmographia website: https://www.cosmos.esa.int/web/spice/cosmographia
SPICE kernels are available on the same website under Missions -> JUICE, direct URL is https://www.cosmos.esa.int/web/spice/spice-for-juice
Keep in mind that SPICE kernels are very large, at the time of writing this tutorial kernels for JUICE were 1.82 GB in total.
Basic download of SPICE Kernels
ftp://spiftp.esac.esa.int/data/SPICE/JUICE/kernels). Download files into
C:\SPICEkernels\2017\– that’s the directory we’ll use further down in this tutorial.
Illustrated download of SPICE kernels in FileZilla
ftp://spiftp.esac.esa.int/data/SPICE/JUICE/kernels), run FileZilla, paste the link into Host window, click Quickconnect. Once connection is established in a left field open
C:\SPICEkernels\2017\, select all directories from the right window, drag & drop them to the left side, and wait until everything is downloaded.
Once all the files are downloaded we can begin with installation of Cosmographia. Run
cosmo-installer-3.0-windows.exe and install the application. You do not need any Extras, so leave these unchecked during the setup. Don’t run Cosmographia once installation is completed.
Next step is to extract JSON definition files that we will be opening with Cosmographia. For the sake of simplicity in this example we’ll extract content of the Zipped package (
C:\SPICEkernels\Cosmographia\. Once archive is extracted you’ll have to edit the file
\kernels\juice_crema_3_1_cosmo.tm – it’s a standard text file, can be opened it any plain text editor, such as ConTEXT or Notepad++ (Do not edit this file with Windows Notepad as the file is using non-windows line breaks, which are not respected by Notepad). Inside of that file you’ll have to change PATH_VALUES to:
PATH_VALUES = ( 'C:\SPICEkernels\2017' )
Here is where to find it inside of the
We’re ready to run the simulation. Open Cosmographia, pick File -> Open Catalog
C:\SPICEkernels\Cosmographia\scenarios\ and open file
load_JUICE_crema_3_1_001.json – that’s the most basic scenario which shows JUICE flying through the solar system and then around the Moons of Jupiter.
To make it clearer, make sure that planet orbits are visible under Guides menu:
Basic controls in Cosmographia are as follows:
- Left mouse button
- rotate around current point of focus
- Right mouse button
- look around (for beginners I’d advise against using it)
- Double click
- change point of focus and go to it
- cancel current movement
- Mouse scroll down
- zoom out
- Mouse scroll up
- zoom in
You are now ready to play with solar system simulation that will display the entire span of the mission. Keep in mind that over time both: SPICE data and JSON files will be updated by ESA as they plan new observations and make these visualizations available to public.
Error loading kernel: ‘(…)../kernels/juice_crema_3_1_cosmo.tm’
PATH_VALUES inside of the indicated .tm file is not pointing to the directory that contains SPICE data.
Error Item ‘JUICE_SWI’: Unknown instrument ‘JUICE_SWI’ for SPICE Sensor.
At the time of writing this article that error appears after opening
load_JUICE_crema_3_1_all_sensors_001.json, it’s due to the issue with files provided, and it doesn’t affect working of the simulation. It will simply display all the instruments but the one that errored (in this case: SWI – Sub-millimeter Wave Instrument)