Celestia
Celestia: A free desktop simulator for exploring and customizing a detailed 3D universe. Ranked #25 of 34 in Astronomy Apps by our editors (6.6/10); pricing: Free plan; best for free customizable 3D space exploration.
At a glance
- Editor score6.6 / 10
- PricingFree plan
- Best forFree customizable 3D space exploration
- Free planYes
- Paid fromFree
- Facts checked21 Sep 2026
Where it wins
- Free, open-source 3D simulation across Windows, macOS and Linux
- Navigate stars, planets, moons, spacecraft, galaxies and other objects
- Add catalogs and customize the experience with Lua scripting
Where it doesn't
- Desktop-focused, with no mobile coverage
- No verified telescope control
- Catalog and scripting customization may suit technical users better
Our verdict on Celestia
Celestia is a free, open-source desktop astronomy application for exploring space in three dimensions. It is designed for users who want to navigate among stars, planets, moons, spacecraft, galaxies and other objects rather than view a simple static sky map. Support for Windows, macOS and Unix-like systems including GNU/Linux gives it cross-platform desktop coverage. A Guided Tour introduces notable objects, while object selection works through names, catalog numbers or designations.
Its strongest distinction is the combination of real-time 3D navigation and user customization. The Star Browser provides lists of nearest, brightest and planet-hosting stars, and the Solar System Browser helps users select objects within the solar system. Additional solar-system, star and deep-sky catalog files can be added, and Lua scripting support allows further changes to the experience. These tools make Celestia a good fit for learners, educators, hobbyists and technically inclined users who want to explore beyond a fixed set of views.
Celestia is less suitable for users who need a mobile astronomy app or verified telescope control. Its published platform coverage is Windows, macOS and Linux, keeping the experience centered on desktop systems. The catalog and scripting options also make it more focused on exploration and customization than on a simplified, guided experience for casual skywatching. Choose Celestia for free, configurable 3D space exploration and broad object navigation; choose an alternative if mobile access or telescope operation is central to your workflow.
Your product? Our editors can test Celestia in depth and publish a review, labelled as paid · from $149/mo →
Celestia pricing
Celestia fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Offline access | Not verified |
| Platform coverage | Cross-platform |
| AR sky view | Not verified |
| Telescope control | Not verified |
| Mission tracking | Not verified |
| Catalog size | Not verified |
| Learning content | Not verified |
| Deployment | Desktop |
| Platforms | Windows, macOS, Linux |
| Support | Community, Docs |
| Built for | Solo, Small business, Mid-market, Enterprise (editorial estimate) |
| Pricing | Free plan |
| Website | celestiaproject.space |
| Facts checked | 21 Sep 2026 |
Alternatives to Celestia
- StellariumA capable free desktop planetarium with telescope control, scripting, and offline access.9.3
- KStarsA capable free desktop toolkit for sky simulation, planning, and astrophotography.9.2
- WorldWide TelescopeA free, open-source astronomy platform for visualization, tours, and telescope projects.9.1
See all Celestia alternatives →
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The editor score above is our own research. What this page doesn't have yet is a reader's view — what you used Celestia for, what worked and what didn't. No stars are seeded and no review is paid for; an editor reads every one before it appears.
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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