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 Prefectures of Japan, prefecture of Japan located in the Tōhoku region of Honshu. It is the second-largest Japanese prefecture (behind Hokkaido) at , with a population of 1,165,886 (as of July 1, 2023). Iwate Prefecture borders Aomori Pre ...

, 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-defence; military and law enforcement applications; competition; physical, mental, and spiritual development; entertainment; and the pres ...

, and his wife, Kisei. Tanakadate studied English at

Keio-Gijuku University , abbreviated as or , is a private research university located in Minato, Tokyo, Japan. It was originally established as a school for Western studies in 1858 in Edo. It was granted university status in 1920, becoming one of the first private ...

starting in 1884, and graduated from

Tokyo Imperial University The University of Tokyo (, abbreviated as in Japanese and UTokyo in English) is a public university, public research university in Bunkyō, Tokyo, Japan. Founded in 1877 as the nation's first modern university by the merger of several Edo peri ...

in 1882 with a degree in

physics Physics is the scientific study of matter, its Elementary particle, 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 whi ...

. He developed a way to write Japanese in the

Latin alphabet The Latin alphabet, also known as the Roman alphabet, is the collection of letters originally used by the Ancient Rome, ancient Romans to write the Latin language. Largely unaltered except several letters splitting—i.e. from , and from � ...

called ''Nihon-shiki'' or ''Nippon-shiki'' in 1885, later becoming president of the Japanese Romanization Society. In the lead up to the

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, 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, he was the Professor of Natural Philosophy (Glasgow), professor of Natur ...

Glasgow University The University of Glasgow (abbreviated as ''Glas.'' in post-nominals; ) is a public research university in Glasgow, Scotland. Founded by papal bull in , it is the fourth-oldest university in the English-speaking world and one of Scotland's four ...

in Scotland, and with others in

Berlin Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...

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

Royal Society of Edinburgh The Royal Society of Edinburgh (RSE) 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 establis ...

. 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, ''hy ...

and

Magnus Maclean Magnus Maclean FRSE MIEE MICE LLD (1 November 1857 – 2 September 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 su ...

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

gravity In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force b ...

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 Association of Geodesy, International Geodetic Association in 1899 to study variations in latitude caused by polar motion, Precession (astronomy), precession, or Chandl ...

(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 is the design, development and use of military aircraft and other flying machines for the purposes of conducting or enabling aerial warfare, including national airlift (air cargo) capacity to provide military logistics, logist ...

. In the

Russo-Japanese War The Russo-Japanese War (8 February 1904 – 5 September 1905) was fought between the Russian Empire and the Empire of Japan over rival imperial ambitions in Manchuria and the Korean Empire. The major land battles of the war were fought on the ...

, he was an advisor to the

Imperial Japanese army The Imperial Japanese Army (IJA; , ''Dai-Nippon Teikoku Rikugun'', "Army of the Greater Japanese Empire") was the principal ground force of the Empire of Japan from 1871 to 1945. It played a central role in Japan’s rapid modernization during th ...

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 carri ...

s for

military reconnaissance In military operations, military reconnaissance () or scouting is the exploration of an area by military forces to obtain information about enemy forces, the terrain, and civil activities in the area of operations. In military jargon, reconnai ...

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 A wind tunnel is "an apparatus for producing a controlled stream of air for conducting aerodynamic experiments". The experiment is conducted in the test section of the wind tunnel and a complete tunnel configuration includes air ducting to and f ...

. Tanakadate published dozens of articles on

aeronautics Aeronautics is the science or art involved with the study, design process, design, and manufacturing of air flight-capable machines, and the techniques of operating aircraft and rockets within the atmosphere. While the term originally referred ...

and

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

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 The University of Tokyo (, abbreviated as in Japanese and UTokyo in English) is a public research university in Bunkyō, Tokyo, Japan. Founded in 1877 as the nation's first modern university by the merger of several pre-westernisation era ins ...

. Tanakadate was the first Japanese member of the

International Committee for Weights and Measures The General Conference on Weights and Measures (abbreviated CGPM from the ) is the supreme authority of the International Bureau of Weights and Measures (BIPM), the intergovernmental organization established in 1875 under the terms of the Metre C ...

and helped arrange the official adoption of the

metric system The metric system is a system of measurement that standardization, standardizes a set of base units and a nomenclature for describing relatively large and small quantities via decimal-based multiplicative unit prefixes. Though the rules gover ...

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 , transcription_name = ''Kokkai'' , legislature = 215th Session of the National Diet , coa_pic = Flag of Japan.svg , house_type = Bicameral , houses = , foundation=29 November 1890(), leader1_type ...

. 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, officially the Tokyo Metropolis, is the capital of Japan, capital and List of cities in Japan, most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is List of largest cities, one of the most ...

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

Recognition

* 1902 –

Order of the Rising Sun The is a Japanese honors system, 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 feat ...

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

, 2nd class * 1916 – Grand Cordon of the

Order of the Sacred Treasure The is a Japanese Order (distinction), 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 c ...

* 1944 –

Order of Culture The is a Japanese Order (decoration), order, established on February 11, 1937. The order has one class only, and may be awarded to men and women for contributions to Japanese Art, Japan's art, Japanese Literature, literature, science, technolog ...

, 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 is an object made to memorialize something. Commemorative may refer to: * Commemorative coin, coins that issued to commemorate something * Commemorative medal, a medal to commemorate something * Commemorative plaque, a plate typic ...

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

Gallery

File:Tanakadate Aikitsu in 1890.jpg, Tanakadate in 1890 File:NakamuraTsune-1916-Portrait of Dr.Tanakadate.png, Portrait by

Nakamura Tsune (3 July 1887 – 24 December 1924) was a Japanese yōga painter best known for his portraits of Sōma Toshiko, including ''Girl'' (1914). Life Nakamura Tsune was born in 1887 in what is now Mito City, into a family that had served as sam ...

, 1916 File:Tanakadate Aikitsu 2.jpg File:Tanakadate Aikitsu photographed by Shigeru Tamura.jpg

References

External links

* {{DEFAULTSORT:Tanakadate, Aikitsu Japanese physicists University of Tokyo alumni Alumni of the University of Glasgow Academic staff of the University of Tokyo 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 Scientists from Iwate Prefecture 1856 births 1952 deaths Fellows of the Royal Society of Edinburgh Kazoku