was a Japanese scientist and optician.
Biography
He was born in
Kaizuka, Osaka
270px, Kaizuka CIty Hall
is a city located in Osaka Prefecture, Japan. , the city had an estimated population of 83,995 in 37,778 households and a population density of 1900 persons per km². The total area of the city is .
Geography
Kaizuka ...
, in a merchant family, became independent to be an optician, then was interested in natural science and learned scientific methodology and physics from Minagawa Kien, a scholar of ''
I Ching
The ''I Ching'' or ''Yi Jing'' (, ), usually translated ''Book of Changes'' or ''Classic of Changes'', is an ancient Chinese divination text that is among the oldest of the Chinese classics. Originally a divination manual in the Western Zho ...
'', in
Kyoto
Kyoto (; Japanese: , ''Kyōto'' ), officially , is the capital city of Kyoto Prefecture in Japan. Located in the Kansai region on the island of Honshu, Kyoto forms a part of the Keihanshin metropolitan area along with Osaka and Kobe. , the ci ...
. He observed movements of the sun, the moon, stars, and developed an instrument to calculate the movements of celestial bodies and tides called ''Heitengi'' (平天儀) in 1801 and wrote the theoretical book of astronomy called ''Heitengi zukai'' (平天儀図解) in 1802.
Zenbei researched some imported optical instruments, then in 1793, made his first telescope. It had quite a good reputation then he made many telescopes of Galileo type and Kepler type, which widely used among astronomers and
feudal rulers. His descendants became telescope makers for four generations.
Zenbei Land, an education center for astronomy and its history named in honor of Zenbei, equipped with a 600 mm diameter newtonian/cassegrain reflector, has been open to public since 1992 by Kaizuka municipal government.
An asteroid
7538 Zenbei was named after him.
References
An Iwahashi's telescope as a historical heritage of Osaka PrefectureZenbei Land homepage
{{DEFAULTSORT:Iwahashi, Zenbei
1756 births
1811 deaths
Opticians
18th-century Japanese astronomers
People from Kaizuka, Osaka
Telescope manufacturers
19th-century Japanese astronomers