This project generates a ground track for a given orbiting object and reports upcoming visible passes from a reference (observation) location. It will also plot the ground track while the object is visible at the reference location.
Python modules are defined in requirements.txt. Basemap is an extension of matplotlib that enables ground track plotting, requiring the GEOS library. For installation instructions, see https://matplotlib.org/basemap/users/installing.html.
In order to generate a ground track, run initialize_track.py. To see all options:
python initialize_track -h.
Initial conditions are required. To input Keplerian orbit elements, write a file in the following format (one per line):
epoch (UTC) semi-major axis (m) eccentricity inclination (deg) true anomaly (deg) RAAN (deg) argument of perigee (deg)
To input a TLE, supply a file with the TLE, or supply a NORAD satellite identifier, and the script will fetch the most recent TLE from space-track.org. In order to fetch from space-track.org, you must supply user credentials as environment variables SATCAT_USER and SATCAT_PASSWORD.
Example initial condition files are ex_ic.kep and ex_ic.tle.
To view observable passes, you must supply the observation coordinates in a file. Use the following format:
<LAT (N)> <LON (E)>, in DMS
39-45-43, -104-52-52 represents 39˚45'43'' N, -104˚52'52''E
Given that the initial conditions are sourced from TLEs, observable passes will only be generated for the next three days, by default.
Example observation coordinates file is ex_rc.txt
The reference ground track will be saved in the base project directory at ground_track.png. If specified, the visible pass plots will be found in the Plots/ folder.