Johann Caspar Horner (Zürich, 12 March 1774 – Zürich, 3 November 1834) was a Swiss physicist, mathematician and astronomer.

Life

At the beginning, he wanted to be a priest, but later he went to Göttingen, where he learnt astronomy. Then he traveled throughout the world for three years on behalf of the Russians. After the journey he took two years in Saint Petersburg with the cataloging the items he had found. He discovered a method for approaching the roots of equation with unknown factor in a higher power. His findings were published under the titles Über die Curven zweiten Grades and Die fünf regelmässigen Körper. He wrote some other works also on the field of astronomy. In 1805, Johann Caspar Horner visited Japan with the Prussian Georg Heinrich von Langsdorff, as a scientist to the Krusenstern mission that also brought the Russian ambassador Nikolai Rezanov to Japan. Horner made a hot air balloon out of Japanese paper (washi), and made a demonstration in front of about 30 Japanese delegates. This followed the first flight of a hot air balloon by the brothers Montgolfier in France in 1783.

Books and publications