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Life & fun · alternatives · 2026

HO

24 alternatives to Harmony of the Spheres – Gravity Simulator

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

Harmony of the Spheres is a 3D gravity simulator that lets users explore gravitational physics through interactive scenarios based on real solar systems and fictional setups. Users can add planets, modify gravitational… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 3 we have checked on their own sites, 3 of them free or with a free tier. Harmony of the Spheres – Gravity Simulator launched in 2018; newer entries below may have overtaken it.

  1. 1GI

    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…

    Jun 2026 · qunabu.github.io · its alternatives →

  2. 2
    Atlas of Spacefree▲770

    Hello 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…

    2025 · atlasof.space · its alternatives →

  3. 3

    Gravity WebGL experiment in the Solar System

    2016 · github.com · its alternatives →

  4. 4IB
  5. 5IB
  6. 6

    Features include: - Several preset periodic orbits: the classic Figure-8, plus newly discovered 3D solutions from Li and Liao's recent database of 10,000+ orbits (https://arxiv.org/html/2508.08568v1) - Full 3D camera controls (rotate/pan/zoom) with body-following mode - Force and velocity vector visualization - Timeline scrubbing to explore the full orbital period The 3D presets are particularly interesting. Try "O₂(1.2)" or "Piano O₆(0.6)" from the Load Presets menu to see configurations where bodies weave in and out of the orbital plane. Most browser…

    Nov 2025 · trisolarchaos.com · its alternatives →

  7. 7

    Drop the balls in different celestial bodies

    2022 · its alternatives →

  8. 8

    I was wondering how I can arrange objects along a spherical helix path, and read some articles on it. I ended up learning about parametric equations again, and make this visualization to document what I learned: https://visualrambling.space/moving-objects-in-3d/ feel free to visit and let me know what you think!

    2025 · visualrambling.space · its alternatives →

  9. 9WI

    Special relativity simulator in which light crawls along at a human speed, so Lorentz contraction, aberration and Doppler shift happen at walking pace.

    Sep 2026 · rivendell.dmitrybrant.com · its alternatives →

  10. 10
    AstraPixelsfree tier, from $5/mo▲267

    ​​A pixel-art solar system at its real current positions.​

    Aug 2026 · astrapixels.com · its alternatives →

  11. 11

    Explore a free 3D space simulator in your browser. Travel across the Solar System, change time, inspect source-backed worlds, and collect postcards.

    Jul 2026 · spacesim.co · its alternatives →

  12. 12

    Download Black Hole Vision by Alexandru Lupsasca on the App Store. See screenshots, ratings and reviews, user tips, and more apps like Black Hole Vision.

    2024 · apps.apple.com · its alternatives →

  13. 13AS

    I really like the look of the famous album art for Unknown Pleasures [1]. It was originally created by Harold Craft at the Arecibo Observatory from the signals of the first discovered radio pulsar [2]. I made a spectrogram that produces a similar look. It runs FFT in Rust and visualizes it with WebGL. [1]: https://en.wikipedia.org/wiki/File:UnknownPleasuresVinyl.jpg [2]: https://en.wikipedia.org/wiki/PSR_B1919%2B21

    2024 · aestuans.github.io · its alternatives →

  14. 14
    AstroGrid▲113

    Explore the entire universe in your browser, in real 3D

    Apr 2026 · velonspace.com · its alternatives →

  15. 15

    I (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 /…

    Jan 2026 · donutthejedi.com · its alternatives →

  16. 16IA

    Somewhat inspired by a recent post here, I also made a three-body simulation on a whim, meaning to try out macroquad[0] (verdict: really nice!). Thanks to the engine I could trivially target wasm as well, so others can get mesmerized too. The source is available here: https://github.com/sulami/three-bodies [0]: https://docs.rs/macroquad/latest/macroquad

    2024 · three-bodies.sulami.xyz · its alternatives →

  17. 17

    Walk in the cosmos

    2021 · its alternatives →

  18. 18IM

    I made this site using R3F (https://github.com/pmndrs/react-three-fiber), a React renderer for 3JS (https://threejs.org/). The celestial bodies are Three.JS meshes. I used loaders (namely 'useLoader' from R3F and 'GLTFLoader' from 3JS) to import 3D models, such as International Space Station. More on loading models in R3F: https://docs.pmnd.rs/react-three-fiber/tutorials/loading-mod... I've future plans for this side project. It would be great to hear from the HN community before diving into them. Enjoy! P.S: Getting an empty…

    2022 · spaceinbrowser.com · its alternatives →

  19. 19

    This is a little hobby project that I hope you enjoy. You can see where the International Space Station is now, with live HD video from NASA, on a realistic 3D globe. The positions of the sun and moon are also accurate, though distances aren't to scale. The clouds are also near-realtime; I span that out into a separate project at https://clouds.matteason.co.uk, where the cloud images I create from EUMETSAT data are freely available. I've got more features almost ready to go, like the ability to turn off all UI, toggleable clouds and turning off the day/night cycle I'd love for…

    2024 · iss.matteason.co.uk · its alternatives →

  20. 20

    I started teaching my daughter physics by showing her how things actually work - plucking guitar strings to explain vibration, mixing paints to understand light, dropping objects to see gravity in action. She learned so much faster through hands-on exploration than through books or videos. That's when I realized: what if I could recreate these physical experiments as interactive simulations? Lumen is the result - an interactive physics playground covering sound, light, motion, life, and mechanics. Each module lets you manipulate variables in real-time and see/hear the results…

    Jan 2026 · projectlumen.app · its alternatives →

  21. 21

    A tediously accurate scale model of the solar system

    2014 · joshworth.com · its alternatives →

  22. 22

    A gravity simulator, with updated movement controls

    2016 · valentinvichnal.github.io · its alternatives →

  23. 23

    3D physics space puzzle — merge planets to reignite the Sun!

    Jul 2026 · mergeplanets.promptlab.me · its alternatives →

  24. 24

    I made a GLSL shader that bends 3D space using a 4D hypersphere projection. The idea: 1. Project a model onto a 4D sphere 2. Rotate the sphere 3. Project the model back to 3D Code and details: https://github.com/bntre/CurvedSpaceShader Curious what you think.

    2025 · github.com · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →