Pierre Léna, born in 1937, is a French astrophysicist, former student of the École normale supérieure, Emeritus Professor (Observatoire de Paris-PSL & Université Paris-Cité). His scientific work accompanied the emergence of infrared astronomy, developing observation from telescopes on Earth, in aircrafts and spaceborne. In search of high-resolution images, he was one of the architects of the European Very Large Telescope in Chile, with interferometry and adaptive optics. Elected to the Académie des sciences in 1991, committed to science education, he joined physicists Georges Charpak & Yves Quéré to create La main à la pâte in 1995. He chaired this Foundation (2011-2014) and then created the Office for Climate Education in 2018. Pierre Léna has four children and twelve grandchildren.