Jean-Françcois Denisse

Jean-François Denisse passed away on 17 November 2014, aged 99. He was one of the pioneers of radio astronomy and its main promoter in France. He served as President of IAU Commission 40 from 1955 to 1961.

Denisse was born in 1915 in an artist family. After studies at École Normale Supé:rieure, he moved in 1942 to Dakar in Senegal, then a French colony, to teach physics. Back to Paris in 1946, he entered the Physics Laboratory of École Normale Supérieure whose director, Yves Rocard, was interested in radio astronomy and founded a small group in 1947 of which Denisse was a member. After his PhD obtained in 1950 on the propagation of waves in plasmas, he became the head of this group in 1953, at the time when radio astronomy moved to the Paris-Meudon Observatory. He created the radio astronomy station in Nançay, whose first large instrument was a solar interferometer completed in 1956. He then conceived and realized the large radio telescope, completed in 1967 and still in operation. In 1963, he was appointed director of the Paris Observatory. This was the end of his purely scientific work devoted principally to solar radio astronomy, and the beginning of a remarkable administrative career: he contributed in a fundamental way to the development of French and European astronomy from the ground and from space.

Denisse, who was my thesis advisor, was an amiable, lively and modest person, but with considerable insight and strength in his realisations. He will be remembered together with Emile-Jacques Blum and Jean-Louis Steinberg as the founder of French radio astronomy, and also as one of the most influential developers of astronomy in France and in Europe.