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SpaceEngineGaia Sky
Paid

A paid purchase, sold through Steam.

 Free

Free and open source under the MPL-2.0.

Windows Windows, macOS, Linux
  • Seamless travel from galactic scale to planetary surfaces
  • Real catalogued objects mixed with scientifically based procedural systems
  • Uses real scientific catalogs including Gaia star data
  • Handles around a billion objects in real time
  • Paid software
  • Procedurally generated regions are plausible models, not observed data
  • Large datasets need significant download space and capable hardware
  • Aimed at scientific exploration rather than a guided planetarium experience
Downloadable app Downloadable app
Closed source Open source
License not stated License: MPL-2.0
Not stated if an account is needed No account needed
Not stated if it works offline Not stated if it works offline

Checked September 24, 2026

Checked October 1, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.