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Life & fun · April 30, 2026

AstroCalcul

Learn math by exploring the Solar System. Ad-free & Privacy

What it does

I built AstroCalcul because I couldn't find a math app for my 7-year-old daughter that wasn't a "slot machine" of ads and subscriptions. AstroCalcul turns math drills into a space odyssey. Instead of boring lists, children explore a 3D-style solar system where every multiplication or division unlocks real facts about planets. Key features: Privacy-First: No ads, no trackers, no data collection. Educational Depth: Learn astronomy and math simultaneously.

Does the same job

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  • AO
    Atlas of Space2025 · atlasof.space · ▲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…

  • AA
    Astro App2024 · astro.sshh.io · ▲291

    I really like Stellarium and SkySafari but I felt like these are primarily geared towards exploring the sky but not so much "here are the long list of things I want to see, when can I see them tonight and where". There's also not really a great option I've found that combines sky object planning + location weather details while still being free so I built this. The UI's heavily inspired by NINAs sky atlas + Robinhood. Right now you can: View the altitude chart of objects and 3D view Create lists of objects of interest View the annual max/min daily altitude of an object to find the best…

  • AstraPixels29d ago · astrapixels.com · ▲267

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

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

  • AS
    A solar system simulation in the browserDec 2025 · luna.watermelonson.com · ▲13

    I didn't realize Universe Sandbox ran on MacOS, and I was in the mood to play around a bit. Some functions it's got: - Random system generation - Sonification is super fun too - Habitability Simulation (Just for fun, don't cite this please) - Replacing, spawning, deleting objects I've had tons of fun building this, so I hope someone else can share the joy. It's free and runs in the browser. I'd love to hear any feedback. I think this is at a state where I might leave it as it is, but if people are interested in other features, maybe I'll keep working on it. I've kept saying I'll stop working…

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    A tediously accurate scale model of the solar system

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