Life & fun · alternatives · 2026
24 alternatives to Celestial Vehicle Propulsion Simulator
3D simulator that models planets, orbits, propulsion systems
Celestial Vehicle Propulsion Simulator is a 3D interactive tool that models space travel within our solar system using real astronomical data and physics calculations. Users can pilot spacecraft between planets using… 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.
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- 2GI
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 →
- 3

Lunar lander type game with computational fluid dynamics - s-macke/Interplanetary-Postal-Service
2018 · github.com · its alternatives →
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- 5
Atlas of Spacefree▲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…
2025 · atlasof.space · its alternatives →
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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 →
- 7MS
Did this a few years ago. Seems apropos. Sources and more here: https://github.com/EngineersNeedArt/Mooncraft2000
Apr 2026 · mooncraft2000.com · its alternatives →
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Pilot the SpaceX Dragon 2 vehicle to the ISS!
2020 · iss-sim.spacex.com · its alternatives →
- 9

I built this with Claude cause I always wanted to tinker with a simulation economoy and I love space themes. A space-economy sim where nothing is scripted. A few hundred autonomous ships each run their own planner. Some chase the best trade route, take a delivery contract, refuel, retrofit at a shipyard, or dock so the crew can rest before morale tanks. Markets price everything off supply with shortage-urgency multipliers, factions tax and subsidize, populations migrate when they're unhappy, and stations that go broke get abandoned and rot. It started as an Elixir/Phoenix prototype, but…
Jul 2026 · github.com · its alternatives →
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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 →
- 11IB
Mar 2026 · structuredlabs.github.io · its alternatives →
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Fully automated SpaceX ISS Dragon docking simulator system. - danirukun/spacex-iss-docking-sim-autopilot
2020 · github.com · its alternatives →
- 13WI
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 →
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Second only to working at Space X
2015 · kerbalspaceprogram.com · its alternatives →
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AstroGrid▲113Explore the entire universe in your browser, in real 3D
Apr 2026 · velonspace.com · its alternatives →
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SpaceSim▲7Explore 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 →
- 17SP
2014 · stefanom.org · its alternatives →
- 18HO
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
2018 · thehappykoala.github.io · its alternatives →
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A thrust-vectoring model rocket flight computer. Comes with all you need to keep your rocket pointing up. - AdamMarciniak/CygnusX1
2020 · github.com · its alternatives →
- 21

An open world starship simulator (Early Access Game)
2015 · store.steampowered.com · its alternatives →
- 22IM
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 →
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AstraPixelsfree tier, from $5/mo▲267A pixel-art solar system at its real current positions.
Aug 2026 · astrapixels.com · its alternatives →
- 24

Explore the solar system in real-time 3D with actual physics
Feb 2026 · spacetrekk.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 →