was a Japanese physicist with diverse interests and effect. His given name was also written as Aikitu.

Biography

Tanakadate was born in Fukuoka hamlet, in what is now part of the city of

Ninohe is a city located in Iwate Prefecture, Japan. , the city had an estimated population of 26,344, and a population density of 63 persons per km2 in 11,803 households. The total area of the city is . Geography Ninohe is located in far north-center ...

in the northern

Iwate Prefecture is a prefecture of Japan located in the Tōhoku region of Honshu. It is the second-largest Japanese prefecture at , with a population of 1,210,534 (as of October 1, 2020). Iwate Prefecture borders Aomori Prefecture to the north, Akita Prefectur ...

, Japan. He was the son of Tanakadate Inazo, a teacher of '' Jitsuyo'', a

martial art Martial arts are codified systems and traditions of combat practiced for a number of reasons such as self-defense; military and law enforcement applications; competition; physical, mental, and spiritual development; entertainment; and the preserv ...

, and his wife, Kisei. Tanakadate studied English at

Keio-Gijuku University , mottoeng = The pen is mightier than the sword , type = Private research coeducational higher education institution , established = 1858 , founder = Yukichi Fukuzawa , endowment ...

starting in 1873, and graduated from

Tokyo Imperial University , abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project by ...

in 1882 with a degree in

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

. He developed a way to write Japanese in the

Latin alphabet The Latin alphabet or Roman alphabet is the collection of letters originally used by the ancient Romans to write the Latin language. Largely unaltered with the exception of extensions (such as diacritics), it used to write English and the o ...

called ''Nihon-shiki'' or ''Nippon-shiki'' in 1885, later becoming president of the Japanese Romanization Society. In the lead up to the second world war, he advocated directly for Nippon-shiki over Hepburn, eventually resulting in its adoption as the official Romanization standard by the wartime government. He visited Europe many times, and from 1888 to 1890 worked with

Lord Kelvin William Thomson, 1st Baron Kelvin, (26 June 182417 December 1907) was a British mathematician, Mathematical physics, mathematical physicist and engineer born in Belfast. Professor of Natural Philosophy (Glasgow), Professor of Natural Philoso ...

Glasgow University , image = UofG Coat of Arms.png , image_size = 150px , caption = Coat of arms Flag , latin_name = Universitas Glasguensis , motto = la, Via, Veritas, Vita , ...

in Scotland, and with others in

Berlin Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constitue ...

in Germany. Whilst in Scotland he was elected a Fellow of the

Royal Society of Edinburgh The Royal Society of Edinburgh is Scotland's national academy of science and letters. It is a registered charity that operates on a wholly independent and non-partisan basis and provides public benefit throughout Scotland. It was established i ...

. His proposers were

James Thomson Bottomley James Thomson Bottomley (10 January 1845 – 18 May 1926) was an Irish-born British physicist. He is noted for his work on thermal radiation and on his creation of 4-figure logarithm tables, used to convert long multiplication and division ca ...

James Alfred Ewing Sir James Alfred Ewing MInstitCE (27 March 1855 − 7 January 1935) was a Scottish physicist and engineer, best known for his work on the magnetic properties of metals and, in particular, for his discovery of, and coinage of the word, '' h ...

and

Magnus Maclean Prof Magnus Maclean FRSE MIEE MICE LLD (1857-1937) was an electrical engineer who assisted Lord Kelvin in his electrical experiments and later became Professor of Electrical Engineering in Glasgow (one of the first to hold such a title). The Magnu ...

. Tanakadate travelled widely in Japan from 1893 to 1896, making a survey of

gravity In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the stro ...

and geomagnetism for geophysical research with

Cargill Gilston Knott Cargill Gilston Knott FRS, FRSE LLD (30 June 1856 – 26 October 1922) was a Scottish physicist and mathematician who was a pioneer in seismological research. He spent his early career in Japan. He later became a Fellow of the Royal Society, ...

. He founded the Institute of Seismology at Tokyo Imperial University.Dr. Aikitu Tanakadate: World-Renowned Geophysicist and Seismologist
by Satio Tanno (President, Aikitu Tanakadate Society). August 31, 1995 The

International Latitude Observatory __NOTOC__ The International Latitude Service was created by the International Geodetic Association in 1899 to study variations in latitude caused by polar motion, precession, or "wobble" of the Earth's axis. The original ''International Latitud ...

(sometimes called the Astro-Geodynamics Observatory) at Mizusawa was founded in 1899 as he had proposed.JPL Small-Body Database Browser on 10300 Tanakadate
at the Jet Propulsion Lab site Tanakadate was also an early proponent of

military aviation Military aviation comprises military aircraft and other flying machines for the purposes of conducting or enabling aerial warfare, including national airlift ( air cargo) capacity to provide logistical supply to forces stationed in a war the ...

. In the

Russo-Japanese War The Russo-Japanese War ( ja, 日露戦争, Nichiro sensō, Japanese-Russian War; russian: Ру́сско-япóнская войнá, Rússko-yapónskaya voyná) was fought between the Empire of Japan and the Russian Empire during 1904 and 1 ...

, he was an advisor to the

Imperial Japanese army The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...

on the use of

hot air balloon A hot air balloon is a lighter-than-air aircraft consisting of a bag, called an envelope, which contains heated air. Suspended beneath is a gondola or wicker basket (in some long-distance or high-altitude balloons, a capsule), which carries p ...

s for

military reconnaissance In military operations, reconnaissance or scouting is the exploration of an area by military forces to obtain information about enemy forces, terrain, and other activities. Examples of reconnaissance include patrolling by troops (skirmishers, ...

purposes. This led to the establishment of an aviation laboratory at

. At a 1907 conference in Paris on the metric system, Tanakadate saw a model of early fixed-wing airplane, and extended his stay in Paris to study further. In his Japanese laboratory he built a

wind tunnel Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

. Tanakadate published dozens of articles on

aeronautics Aeronautics is the science or art involved with the study, design, and manufacturing of air flight–capable machines, and the techniques of operating aircraft and rockets within the atmosphere. The British Royal Aeronautical Society identifies ...

and

aviation Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot air ...

from 1910 to 1916 in both Japanese and in French. He appears to have been the most-published Japanese aeronautical scientist of that period. He founded a department on aviation at

Tokyo University , abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project by ...

. Tanakadate was the first Japanese member of the

International Committee for Weights and Measures The General Conference on Weights and Measures (GCWM; french: Conférence générale des poids et mesures, CGPM) is the supreme authority of the International Bureau of Weights and Measures (BIPM), the intergovernmental organization established i ...

and helped arrange the official adoption of the

metric system The metric system is a system of measurement that succeeded the Decimal, decimalised system based on the metre that had been introduced in French Revolution, France in the 1790s. The historical development of these systems culminated in the d ...

of weights and measures in Japan. From 1925 to 1947, he served as a member of the House of Peers of the

Diet of Japan The is the national legislature of Japan. It is composed of a lower house, called the House of Representatives (, ''Shūgiin''), and an upper house, the House of Councillors (, '' Sangiin''). Both houses are directly elected under a paralle ...

. In 1944, he was awarded the

Asahi Prize The , established in 1929, is an award presented by the Japanese newspaper ''Asahi Shimbun'' and Asahi Shimbun Foundation to honor individuals and groups that have made outstanding accomplishments in the fields of arts and academics and have greatl ...

. He died in

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.468 ...

on 21 May 1952. Some of his papers are kept at

Glasgow University , image = UofG Coat of Arms.png , image_size = 150px , caption = Coat of arms Flag , latin_name = Universitas Glasguensis , motto = la, Via, Veritas, Vita , ...

Recognition

* 1902 –

Order of the Rising Sun The is a Japanese order, established in 1875 by Emperor Meiji. The Order was the first national decoration awarded by the Japanese government, created on 10 April 1875 by decree of the Council of State. The badge features rays of sunlight ...

, 4th class * 1906 – JPN Kyokujitsu-sho 2Class BAR

, 2nd class * 1916 – JPN Zuiho-sho (WW2) 1Class BAR

Grand Cordon of the

Order of the Sacred Treasure The is a Japanese order, established on 4 January 1888 by Emperor Meiji as the Order of Meiji. Originally awarded in eight classes (from 8th to 1st, in ascending order of importance), since 2003 it has been awarded in six classes, the lowest ...

* 1944 –

Order of Culture The is a Japanese order, established on February 11, 1937. The order has one class only, and may be awarded to men and women for contributions to Japan's art, literature, science, technology, or anything related to culture in general; recipien ...

, Member * 1952 – JPN Kyokujitsu-sho 1Class BAR

Grand Cordon of the Order of the Rising Sun (posthumous) An asteroid, 10300 Tanakadate, was named for him in 1989. A

commemorative postage stamp A commemorative stamp is a postage stamp, often issued on a significant date such as an anniversary, to honor or commemorate a place, event, person, or object. The ''subject'' of the commemorative stamp is usually spelled out in print, unlike de ...

was issued in his honor in 2002.https://www.post.japanpost.jp/kitte_hagaki/stamp/tokusyu/2002/1105/index.html Japan Post

References

External links

* {{DEFAULTSORT:Tanakadate, Aikitsu Japanese physicists University of Tokyo alumni Alumni of the University of Glasgow University of Tokyo faculty Members of the House of Peers (Japan) League of Nations people Recipients of the Legion of Honour Recipients of the Order of Culture Grand Cordons of the Order of the Rising Sun Recipients of the Order of the Sacred Treasure, 1st class People from Iwate Prefecture 1856 births 1952 deaths Fellows of the Royal Society of Edinburgh