Celestial Spheres

Celestial Spheres is an interactive astronomy simulator for exploring how humanity has understood the sky. Compare the Ptolemaic, Copernican, Tychonic, and Keplerian models in immersive 3D, then step into the Observatory to explore the real night sky from your chosen location.

Explore Earth, the Sun, Moon, planets, constellations, star fields, retrograde motion, eclipses, day and night, lunar phases, zodiac and north-direction guides, and model-specific distance scales. Move time from minutes to months, zoom through the celestial system, track objects, study planetary paths, and inspect eclipse geometry.

Designed for students, teachers, astronomy enthusiasts, and curious observers who want a visual way to understand the history and geometry of the cosmos. Historical models are represented for education and comparison; some visual scales are adjusted for clarity and are not intended as official astronomical predictions.

Developed by Map of Truth.