SPICE Tutorial

A simple demonstration of some of the capabilities of SPICE is provided in MATLAB. An even briefer example is shown in python and C++ simply for the purposes of demonstrating how the SPICE toolkit can be used in other languages.

The MATLAB and python demos should work natively on any machine, while the C++ demo only provides instructions for building on Linux. It should be relatively straight forward to build on MacOS, but building on Windows without WSL will require some experience in compiling C++ on windows.

Getting the Kernels

Before running any of the example code, you'll need to download the correct kernels. If you are able to execute a bash script (e.g. you are using Linux or WSL) you can simply run the get_kernels.sh script. If you cannot run a bash script on your system (for example, if you are on Windows without WSL), you must manually download the following SPICE kernels:

Included in the Repository:

Link to File	Description	Location to put it	Size
naif0012.tls	Leap Second kernel (LSK)	kernels/generic_kernels/lsk/	5.2Kb
pck00010.tpc	Planetary Constants kernel (PCK)	kernels/generic_kernels/pck/	124Kb
Gravity.tpc	Planetary Gravity kernel (PCK)	kernels/generic_kernels/pck/	15Kb

Required for planets_example.m

Link to File	Description	Location to put it	Size
de430.bsp	Planetary Ephemerides	kernels/generic_kernels/spk/	115MB

Required for saturn_example.m

Link to File	Description	Location to put it	Size
sat441.bsp	Saturn Moons Ephemerides	kernels/generic_kernels/spk/	631Mb

Required for rosetta_example.m

Link to File	Description	Location to put it	Size
CATT_DV_257_03_______00344.BC	Attitude kernel (CK) for Comet 67P	kernels/rosetta_kernels/ck/	2.1Mb
ROS_SC_REC_160101_160601_V01.BC	Attitude kernel (CK) for ROSETTA	kernels/rosetta_kernels/ck/	17Mb
ROS_CHURYUMOV_V01.TF	Frames kernel (FK) for Comet 67P	kernels/rosetta_kernels/fk/	2Kb
ROS_V37.TF	Frames kernel (FK) for ROSETTA	kernels/rosetta_kernels/fk/	237 Kb
ROS_160929_STEP.TSC	Spacecraft Clock kernel (SCLK)	kernels/rosetta_kernels/sclk/	17Kb
RORB_DV_257_02_______00344.BSP	Ephemeris kernel (SPK) for ROSETTA	kernels/rosetta_kernels/spk/	92Mb
CORB_DV_257_02_______00344.BSP	Ephemeris kernel (SPK) for Comet 67P	kernels/rosetta_kernels/spk/	213Kb
ROS_CG_K024_OMSDLAM_N_V1.BDS	Digital Shape kernel (DSK) for Comet 67P	kernels/rosetta_kernels/dsk/	2Mb

Example Code

MATLAB

First, make sure that you have MICE (the MATLAB version of SPICE) downloaded and added to your MATLAB path. Download the correct version for your operating system here: https://naif.jpl.nasa.gov/naif/toolkit_MATLAB.html

Once it is downloaded and added to your MATLAB path, you can simply run any of the MATLAB scripts.

NOTE: Line 7 of each MATLAB script attempts to add MICE to the MATLAB path. If you've added it separately you can comment out this line, or if you want it to be added when the script is run, you can change the path used to the path to wherever you have put the MICE toolbox.

Python

You'll need to install the spiceypy and numpy modules. These can be installed with either the pip or conda package managers (though, I personally always recommend conda or its opensource reimplementation, mambaforge).

Once those are installed, you can simply run python example.py from within the python/ subdirectory of this project.

C++ (Specific instructions for Linux provided)

If you wish to build the C++ project on your own, you'll need to know how to link and compile C++ code on your machine. This will include downloading the correct binaries (which can be found here: https://naif.jpl.nasa.gov/naif/toolkit_C.html), and then linking the cspice binaries and including the SpiceUsr.h file into your project.

Instructions for doing this on a 64-bit linux machine are now provided:

NOTE: If you can run a bash script, you can skip steps 2-5 by running setup.sh from within the cpp/ directory

1. cd cpp (move into the cpp/ example directory)
2. wget https://naif.jpl.nasa.gov/pub/naif/toolkit//C/PC_Linux_GCC_64bit/packages/cspice.tar.Z (Download the cspice.tar.Z)
3. tar -xvf cspice.tar.Z (untar the cspice files)
4. mkdir build; cd build; cmake ..; make (Build the project)
5. mv example ../; cd ../ (Move the compiled example executable back to the cpp/ directory)
6. ./example (run the project. If it cannot be run, try first changing permissions using chmod +x example)

Questions:

If you have any follow-up questions related to SPICE, or any questions/issues related to any of these tutorials, please don't hesitate to reach out to Chris Gnam: [email protected]