The Geometry of Eclipses
This animation illustrates the geometry of eclipses, showing how they can occur only when the earth, moon and sun align "just right".
Why Solar Eclipses Don't Happen Every Month (redone)
This revised animation depicts the view of the Sun from the Earth. Inset is an overview of the Earth-Moon-Sun system to show why the tilt of the moon's orbit with respect to the ecliptic precludes...
Why Solar Eclipses Happen (redone)
This revised animation depicts the view of the Sun from the Earth. Inset is an overview of the Earth-Moon-Sun system to show what geometric conditions are required for an eclipse.
Frame Dragging and the Lense-Thirring Effect
This animation is an artist's conception of the Lense-Thirring Effect, which can create a precession of an orbiting object around a spinning gravitational source.