Open Source
🧪 Early version: this app is still being built and tested. Things may change or break — trying it and telling the makers what you find is a big help.
This comes straight from Celestia’s own GitHub page — it’s free. Need help installing? →
About this app
Celestia is a space simulator with real astronomical data: travel to planets, moons and stars, see them to scale, and jump to any date.
It is free, works offline, and is used in classrooms everywhere.
From the app’s home page
- See the codeHow it’s made — every line is public
- Questions & commentsTalk with the people who make it
- Report a problemTell the makers something is broken
- All versionsOlder downloads and what changed
- LicenseThe rules for using and sharing it
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