"Machina Coelestis" is a significant work by the astronomer Johannes Kepler, published in 1618. The title translates to "Celestial Machine," and it explores the structure of the universe, particularly the motion of celestial bodies. Kepler's work builds on his earlier laws of planetary motion, providing a detailed mathematical framework for understanding the orbits of planets around the Sun. In "Machina Coelestis," Kepler also discusses the concept of the Tychonic system, which combines elements of both the Copernican and Ptolemaic models of the universe. This work contributed to the scientific revolution by challenging existing beliefs and laying the groundwork for modern astronomy.