Parabola Movie

A family of evenly spaced circles overlapping a family of evenly spaced lines gives a conic section whose eccentricity is the ratio of the space between the circles to the space between the lines.

In this case the circle spaces are the same as line spaces, so the eccentricity is one. The conics are parabolas.

The parabolas all share the same focus which is the center of the circle family.

If you squint the parabola moire patterns become easier to see.

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