Gravity – Interactive solar-system simulator, from Newton to Einstein
Just for fun and self education, I've built this over a weekend to teach myself why orbits exist, not just show planets going around. Something that was never clearly explain to me in school. It opens with a guided tour that builds the idea up step by step: two bodies and the equal/opposite force, inertia (the Sun is removed and Earth just drifts straight), then "an orbit is falling and continuously missing," cosmic velocities with a little rocket, Voyager 1 & 2's real gravity assists (the clock runs the actual 1977–1989 dates so the planets orbit into their grand-tour alignment and the…
Gravity – Interactive solar-system simulator, from Newton to Einstein launched on June 9, 2026 with 217 votes, #129 of 22,647 launches that month and more than 99% of that year's launches.
In plain words
Gravity is an interactive solar-system simulator that explains orbital mechanics through hands-on exploration. It opens with a guided tour building understanding from basic physics—Newton's laws, inertia, and gravity—through to Einstein's curved spacetime. Users can watch real gravity assists of Voyager 1 and 2 unfold with actual 1977–1989 dates, adjust cosmic velocities with a virtual rocket, or switch to N-body simulation mode. All bodies use real masses, radii, and orbital elements calculated from Kepler's equation. It's designed for self-education and casual learning about why orbits exist.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
Just for fun and self education, I've built this over a weekend to teach myself why orbits exist, not just show planets going around. Something that was never clearly explain to me in school. It opens with a guided tour that builds the idea up step by step: two bodies and the equal/opposite force, inertia (the…
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Atlas of Space2025 · atlasof.space · ▲770Hello HN! Sharing a recent side project of mine, the Atlas of Space, that I built out to explore the Solar System. As a long-time space nerd, I realized recently that I didn't have a good intuition on the scale, speed, and relative orientation of the celestial bodies around us. So over the break I built out a kind of spatial Wikipedia to click around and learn about planets, moons, asteroids, and other bodies orbiting the Sun. The physics is all simulated in the browser using simple Newtonian mechanics. There's a lot left to do from here, including modeling objects in non-Keplerian orbits…
Rocket Launch and Orbit SimulatorJan 2026 · donutthejedi.com · ▲166I (17y/o) have been developing a rocket launch simulation that allows the user to explore what it's like launching a rocket from earth and putting it into orbit. This idea originally started as an educational simulation but as i've gone more down the rabbit hole the more i've wanted to make it realistic. The problem is that I've never had a formal orbital mechanics class or anything like that so I don't know what I'm missing, what I currently have implemented is: Variable gravity Variable Atmospheric drag (US Standard Atmosphere 1976) Multi-stage rockets Closed-loop guidance /…
- IBI built a gravity simulator in pure CSS2022 · multiplanetary.website · ▲64
- HOHarmony of the Spheres – Gravity Simulator2018 · thehappykoala.github.io · ▲69
3D gravity and space Simulator. Explore and play around with the force of gravity in the context of an array of scenarios from our solar system and beyond. You can add planets, delete the Sun, change the value of the gravitational constant or simply lean back and enjoy the dazzling beauty of the pen
- IBI built an interactive 3D three-body problem simulator in the browserMar 2026 · structuredlabs.github.io · ▲60
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