Forty New Invariants of N-Periodics in the Elliptic Billiard

We present some 40 newfound invariants displayed by N-periodics in the Elliptic Billiard, obtained through experimental exploration. These involve distances, areas, angles and centers of mass of N-periodics and associated polygons (inner, outer, pedal, antipedal). Some depend on the parity of N, others on other positional constraints. A few invariants have already been proven with elegant tools of Analytic and Algebraic Geometry. We welcome reader input to add to the list of proofs.