Over the past decade the free and open-source cross-platform desktop planetarium program Stellarium has gained not only most of the computational accuracy requirements for today’s amateur astronomers, but also unique capabilities for specialized applications in cultural astronomy research and astronomical outreach. A 3D rendering module can put virtual reconstructions of human-made monuments in their surrounding landscape under the day and night skies of their respective epochs, so that the user can investigate and experience the potential connection of architecture, landscape, light and shadow, and the sky. It also played a key role in an exhibition about Stonehenge in Austria.

Exchangeable “skycultures” allow the presentation of constellation patterns and mythological figures of non-Western cultures. Stellarium’s multi-language support allows community-driven translation of the whole program, which predestines its use in education also in minority languages.

Stellarium is developed by a very small core team, but is open to external contributions.

The open-source desktop planetarium Stellarium has become very popular in astronomical education and outreach. Our recent changes aim for its applicability in historical and archaeoastronomical simulation contexts. Apart from visualizing the seemingly perpetual regular motions of the celestial bodies, it can be used to visualize and demonstrate historical solar and lunar eclipses, historical and present comets, meteors, and also novae and supernovae.