In geometry, the Gyroelongated pentagonal birotunda is one of the Johnson solids (J₄₈). It is of a similar construction to other Johnson solids, in particular the Elongated pentagonal orthobirotunda and Elongated pentagonal gyrobirotunda. The difference is that a decagonal antiprism is used in place of the prism, resulting in a twist of 18 degrees between the two pentagonal rotundae.

The 92 Johnson solids were named and described by Norman Johnson in 1966.

External links

• Johnson Solid -- from MathWorld