Author: C. Möstl, Austrian Space Weather Office, GeoSphere Austria
Last update: October 2026
Sample distant retrograde orbits in HEE are available in folder "orbit_files".
If you want to use this for any types of studies, please contact me, see https://helioforecast.space/team
find_dro.ipynb: finds optimized numerical solutions for dro orbits to provide initial conditions
dro.ipynb: main notebook, generates numerical solutions for dro orbits with given initial conditions, makes plots and tables for DRO analyses
animations.ipynb: reads in orbit files from folder orbit_files and makes animations in HEE and in an inertial system
example.ipynb: reads in an orbit file from folder orbit_files and plots a DRO in cartesian and polar coordinates
- environment dro is defined in /env/env_dro.yml, includes only standard packages
- needs ffmpeg for making movies https://www.ffmpeg.org
- file de442.bsp (114 MB) is automatically downloaded when running dro.ipynb for the first time from https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/ to folder kernels/
- spiceypy is used for generating the positions of the planets
St. Cyr+ 2000: https://www.sciencedirect.com/science/article/abs/pii/S1364682600000699?via%3Dihub
Frnka 2010: https://jan.ucc.nau.edu/~ns46/student/2010/Frnka_2010.pdf
Perozzi+ 2017: https://link.springer.com/article/10.1140/epjp/i2017-11644-0
Lugaz+ 2024: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024SW004189
Cicalo+ 2025: https://arxiv.org/abs/2508.02138
Prete+ 2026: https://www.swsc-journal.org/articles/swsc/full_html/2026/01/swsc250088/swsc250088.html
Create a conda environment using the "envs/env_dro.yml", and activate the environment:
conda env create -f env_dro.yml
conda activate dro
