Superegg

In geometry, a superegg is a solid of revolution obtained by rotating an elongated superellipse with exponent greater than 2 around its longest axis. It is a special case of superellipsoid.

Unlike an elongated ellipsoid, an elongated superegg can stand upright on a flat surface, or on top of another superegg.^[1] This is due to its curvature being zero at the tips. The shape was popularized by Danish poet and scientist Piet Hein (1905–1996). Supereggs of various materials, including brass, were sold as novelties or "executive toys" in the 1960s.

^ Gardner, Martin (1977). "Piet Hein's Superellipse". Mathematical Carnival. A New Round-Up of Tantalizers and Puzzles from Scientific American. New York: Vintage Press. pp. 240–254. ISBN 978-0-394-72349-5.

[gardner-1] Gardner, Martin (1977). "Piet Hein's Superellipse". Mathematical Carnival. A New Round-Up of Tantalizers and Puzzles from Scientific American. New York: Vintage Press. pp. 240–254. ISBN 978-0-394-72349-5.

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