In 2025 I programmed a solar system simulation using Newton's laws of motion, where the planets orbit the sun in slight ellipses as a result of forces acting on them causing acceleration. I used the simulation to observe how planetary retrograde occurs and could also explain why there is no visible parallax in the sky.

Features include:

• Real-world accurate values, with force/velocity statistics and a ruler for scale
• The sun and the eight largest planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
• The Moon, Astroid Belt, and Kupier Belt
• Other notable planets: Ceres, Pluto, Haumea, Makemake, Eris
• Alpha Centauri A, the second-closest star visible to Earth. You'll need to zoom out far to see it!

Besides the accurate heliocentric solar system simulation, I also included a Geocentric Model based off of the ideas of ancient Greek philosopher Claudius Ptolemy. This geocentric model has Earth be stationary close to the center of the universe, while all of the other planets and the Sun orbit it in perfect circles with epicycles to account for retrograde.