The Moduli Space of Acute Triangles

Abstract: As an introduction to the concept of "moduli space" we consider the moduli space of similarity classes of acute and right triangles in the plane. This has a map to the moduli space of elliptic curves which is onto and generically three-to-one. The reason is that from any acute or right triangle we can construct an elliptic curve, and every elliptic curve is isomorphic to one constructed this way.