About
Stellarium is a powerful, free, and open-source planetarium for desktop and web. It accurately simulates the night sky in real time, displaying what you would see with the naked eye, binoculars, or a telescope from any location on Earth. With a default catalogue of over 600,000 stars and optional extensions reaching 220 million stars, plus more than 80,000 deep-sky objects, Stellarium provides an astronomically rich experience for educators, hobbyists, and professionals alike. The software features highly realistic atmospheric rendering including sunrise, sunset, and Milky Way visuals. Users can explore constellation artwork and boundaries from over 40 world cultures, browse the full Messier catalogue of nebula images, simulate eclipses, supernovae, novae, and comet tails, and view exoplanet locations. Stellarium also supports binary star movement modelling, all-sky surveys (DSS, HiPS), and 6D astrometry for bright stars. Beyond observation, Stellarium offers a robust scripting interface, HTTP remote control API, fisheye and spheric mirror projections for planetarium domes, and a comprehensive plugin system supporting artificial satellites, ocular simulation, and telescope hardware control. It is highly customizable, allowing users to add solar system objects, custom deep-sky objects, landscapes, scripts, and constellation images. Available on Windows, macOS, Linux, and as a web application, Stellarium is trusted by astronomy educators, researchers, planetarium operators, and stargazing enthusiasts worldwide.
Key Features
- Massive Star & Deep-Sky Catalogue: Default catalogue includes 600,000+ stars and 80,000+ deep-sky objects, expandable to 220 million stars and 1 million deep-sky objects via additional catalogues.
- Realistic Atmosphere & Sky Rendering: Photorealistic rendering of the Milky Way, sunrise, sunset, star twinkling, shooting stars, comet tails, and eclipse simulation in full 3D.
- Multi-Culture Constellation Support: Displays constellation art, boundaries, and asterisms from 40+ world cultures, along with calendars from 35+ cultural traditions.
- Telescope Control & Plugin System: Supports hardware telescope control, an HTTP remote-control API, scripting interface, and a rich plugin ecosystem including artificial satellites and ocular simulation.
- Planetarium & Dome Projections: Supports fisheye projection for planetarium domes and spheric mirror projection for low-cost DIY dome setups, making it suitable for professional installations.
Use Cases
- Astronomy educators using Stellarium to demonstrate star positions, constellation mythology, and celestial events to students in classrooms or planetarium domes.
- Amateur astronomers planning observation sessions by checking star positions, planet visibility, and upcoming meteor showers from their location.
- Planetarium operators using Stellarium's fisheye and dome projection modes to run public sky shows on full-dome displays.
- Researchers and archaeoastronomers simulating historical skies to study how ancient cultures observed and interpreted celestial phenomena.
- Hobbyist stargazers using Stellarium Web to quickly identify what stars and planets are visible tonight without installing any software.
Pros
- Completely Free & Open Source: Stellarium is available at no cost under an open-source license, with no paywalls, subscriptions, or feature limitations.
- Cross-Platform with Web Version: Runs natively on Windows, macOS, and Linux, and also offers a browser-based version (Stellarium Web) requiring no installation.
- Highly Customizable & Extensible: Users can add custom deep-sky objects, landscapes, scripts, constellation images, and solar system bodies, and extend functionality through a robust plugin system.
- Multilingual Interface: Supports dozens of languages, making it accessible to astronomy communities worldwide.
Cons
- No AI or Guided Tour Features: Stellarium lacks AI-powered recommendations or guided learning paths; users must know what to look for or rely on external resources for structured education.
- Steep Learning Curve for Advanced Features: Features like scripting, telescope control, and dome projection require technical knowledge and may be intimidating for casual beginners.
- Dated User Interface: The graphical interface, while functional, feels older compared to modern astronomy apps and may not feel as polished on high-DPI displays.
Frequently Asked Questions
Is Stellarium free to use?
Yes, Stellarium is completely free and open-source. You can download and use it on Windows, macOS, or Linux at no cost, or use Stellarium Web in your browser.
Can I use Stellarium for professional or educational purposes?
Absolutely. Stellarium is widely used by educators, planetarium operators, astronomers, and researchers. Its scripting interface and dome projection support make it suitable for professional installations.
Does Stellarium support telescope control?
Yes, Stellarium includes a telescope control plugin that allows you to interface with compatible telescope hardware directly from the software.
What is Stellarium Web?
Stellarium Web is a browser-based version of Stellarium that requires no download or installation. It offers core sky-viewing features accessible from any modern web browser.
Can I add custom objects or scripts to Stellarium?
Yes. Stellarium supports adding custom deep-sky objects, landscapes, constellation images, solar system bodies from online resources, and automation scripts through its built-in scripting interface.
