Celestia

Real-time 3D space simulation

Education & ScienceGPL-2.0+Windows · macOS · Linux · iOS · Android

About Celestia

Celestia lets you fly through the universe at any speed, viewing planets, moons, spacecraft and stars from any vantage point with scientifically accurate positions.

Celestia is completely free and open source (GPL-2.0+) — no trials, no subscriptions, no locked features. Always download from the official website to avoid bundled malware.

Free alternative to: Paid astronomy simulators

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