Jean Charles Rodolphe Radau (22 January 1835 – 21 December 1911) was an

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

and

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

who worked in

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

at the ''Revue des deux Mondes'' for most of his life. He was the co-founder of the Bulletin Astronomique. Radau was born in Angerburg,

Province of Prussia The Province of Prussia (; ; pl, Prowincja Prusy; csb, Prowincjô Prësë) was a province of Prussia from 1829 to 1878. Prussia was established as a province of the Kingdom of Prussia in 1829 from the provinces of East Prussia and West Prussia ...

(now

Węgorzewo Węgorzewo (until 1946 pl, Węgobork; german: Angerburg, lt, Ungura) is a tourist town on the Angrapa River in northeastern Poland, within the historical region of Masuria. It is the seat of Węgorzewo County in the Warmian-Masurian Voivodeshi ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...

), and after studying in

Königsberg Königsberg (, ) was the historic Prussian city that is now Kaliningrad, Russia. Königsberg was founded in 1255 on the site of the ancient Old Prussian settlement ''Twangste'' by the Teutonic Knights during the Northern Crusades, and was named ...

and working on the

Three-body problem In physics and classical mechanics, the three-body problem is the problem of taking the initial positions and velocities (or momenta) of three point masses and solving for their subsequent motion according to Newton's laws of motion and Newton's ...

, he moved to Paris to collaborate with other scientists. In 1871 he was given the Ph.D. in honor of his work in mathematics. Radau won the Prix Damoiseau of the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...

in 1892 working on planetary perturbations in the motion of the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

. This work was of such a high quality that he was elected to the Academy in 1897. A

crater Crater may refer to: Landforms *Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet *Explosion crater, a hole formed in the ground produced by an explosion near or below the surfac ...

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...

is named in Radau's honor. His publications include the ''Wonders of Acoustics'' (

1867 Events January–March * January 1 – The Covington–Cincinnati Suspension Bridge opens between Cincinnati, Ohio, and Covington, Kentucky, in the United States, becoming the longest single-span bridge in the world. It was renamed a ...

External links

Obituaries

AN 190(1912) 251

1835 births 1911 deaths People from Węgorzewo 19th-century German astronomers 19th-century German mathematicians People from the Province of Prussia Members of the French Academy of Sciences Recipients of the Lalande Prize 20th-century German mathematicians {{Germany-mathematician-stub

See also

External links

Obituaries