Overview A special teaching instrument that visually demonstrates the relative motion between the sun, the earth, and the moon using a simple mechanical linkage. Three small balls represent the sun, the earth, and the moon to make orbital relationships and resulting astronomical phenomena easy to observe. Key benefits Intuitive visualization: Converts abstract orbital mechanics into a clear, handson demonstration that helps students and audiences understand relative motion. Demonstrates multiple phenomena: Uses coordinated movement to show how positions of the three bodies produce observable effects. Rich geographic detail on the earth model: The earth can observe the seven states, the four oceans, the Arctic and Arctic circles, the Tropic of , the equator and the international date line. Stable alignment: The average height of the center of the moon is equal to the height of the center of the earth, ensuring consistent visual alignment during demonstrations. Suitable for educational settings: Designed for classroom, laboratory, and public demonstration use where clear, repeatable presentations are needed. Features Threesphere representation: Small spheres represent the sun, the earth, and the moon, making roles and relationships easy to identify. Mechanical linkage device: Builtin linkage converts rotations and revolutions into coordinated motion so instructors can demonstrate relationships and timing between bodies. Observational markers: The earth model includes key lines and regions to support lessons on latitude, time zones, and global geography. Clear demonstration of relative motion: Movement of the three models together highlights interactions that lead to phases, eclipses, seasonal angles, and day night cycles. Practical applications Classroom demonstration: Use during physics or astronomy lessons to show relative motion, lunar phases, and the geometry behind eclipses. Lab or workshop activity: Let small student groups manipulate the linkage to explore how changing positions affect observed phenomena. Science center or museum display: Offer visitors a handson way to visualize the sun earth moon system and key geographic references. What this product solves Makes complex spatial relationships accessible and memorable through direct visualization. Reduces student confusion about relative positions, timing, and how those lead to common astronomical events. Provides a durable, repeatable tool for instructors to illustrate concepts without complex software or projections. Compatibility and use notes Intended for demonstration use in educational and exhibit environments. used on a stable flat surface for clear observation and safe operation. No special power or software required; operation is mechanical and manual. Materials and performance Mechanical linkage provides repeatable, synchronous motion suitable for classroom pacing. Designed to present consistent visual alignment between models; the average height of the center of the moon is equal to the height of the center of the earth to support accuratelooking demonstrations. What you get A threeball mechanical teaching instrument representing the sun, earth, and moon with linkage for demonstrating their relative motion and associated phenomena. This instrument is a practical, lowtech teaching aid that helps instructors and learners see and explore the relationships between the sun, the earth, and the moon in real time.