Eclipse simulator is a command-line tool for producing animations of solar eclipses. It was written to produce all of the diagrams, KML path files, and video animations that appear on https://in-the-sky.org/. An example of the kinds of media it produces can be seen on this page: https://in-the-sky.org/news.php?id=20201214_09_100

The simulations are based on the DE430 planetary ephemeris computed by the Jet Propulsion Laboratory (JPL). The position of the Sun, Earth and Moon are extracted from the DE430 files using EphemerisCompute (https://github.com/dcf21/ephemeris-compute-de430), written by the author and also freely available for download.

They assume that the Earth and Moon are both ellipsoids with fixed polar and equatorial radii, and do not take into account the irregular topography of either body. All eclipse predictions are made at sea level. In practice, this means that the predictions presented here are inaccurate by at most of few seconds.

eclipse-simulator is written in C and runs in Linux, MacOS, and other Unix-like operating systems. A front-end user interface is written in python3. The simulator does not run under Windows.

This code is distributed under the Gnu General Public License. It is (C) Dominic Ford 2012 - 2020.

Before you start, the simulator needs to download various data from the internet, including the tool ephemerisCompute from the author's GitHub repository, and the DE430 ephemeris files.

This can be done with the Python script solarEclipses.py. The total download size will be around 500 MB. These files are only downloaded the first time this script is run.

The script will then proceed to run some demo simulations; by default it simulates the eclipses of 2020 and 2021. Each simulation takes around 45 minutes on a single core of a modern computer (e.g. Intel i7 8700), or around 120 minutes on a machine dating from around 2010. If your computer has multiple cores, multiple simulations will run on parallel on the various cores.

eclipse-simulator may be used to simulate any solar eclipse within the time span of the DE430 planetary ephemeris - i.e. 1600 to 2200 AD. To simulate a particular eclipse, pass the command-line switches --year-min and --year-max to the Python script solarEclipses.py. For example:

./solarEclipses.py --year-min 2025 --year-max 2030

This code was developed by Dominic Ford https://dcford.org.uk. It is distributed under the Gnu General Public License V3.