Lénárt sphere [SEP] named after
Lénárt sphere is giving hands-on experience of spherical geometry.
History.
The Lénárt sphere was invented by István Lénárt in Hungary in the early 1990s and its use is described in his 2003 book comparing planar and spherical geometry.
Spherical trigonometry used to be an important mathematics topic from antiquity through the end of World War II, and has been replaced in modern education and (in navigation) with more algorithmic methods as well as GPS, including the Haversine formula, linear algebraic matrix multiplication, and Napier's pentagon
Lénárt sphere
A Lénárt sphere is a teaching and educational research model for spherical geometry. The Lénárt sphere is a modern replacement of a "spherical blackboard".
It can be used for visualizing spherical polygons (especially triangles) showing the relationships between the sides and the angles.
Basic set.
The Lenart Sphere Basic Set includes:
- A transparent plastic, eight-inch sphere
- A ring-shaped support, called a torus, to place under the sphere
- Hemispherical transparencies that fit over