Medal in 2006. Alexander Popov was among the inventors of radio, while Nikolai Basov and Alexander Prokhorov were co-inventors of laser and maser. Zhores Alferov contributed significantly to the creation of modern heterostructure physics and electronics. Oleg Losev made crucial contributions in the field of semiconductor junctions, and discovered light-emitting diodes. Vladimir Vernadsky is considered one of the founders of geochemistry, biogeochemistry, and radiogeology. Élie Metchnikoff is known for his groundbreaking research in immunology. Ivan Pavlov is known chiefly for his work in classical conditioning. Lev Landau made fundamental contributions to many areas of theoretical physics. Nikolai Vavilov was best known for having identified the centres of origin of cultivated plants. Trofim Lysenko was known mainly for Lysenkoism. Many famous Russian scientists and inventors were émigrés. Igor Sikorsky was an aviation pioneer. Vladimir Zworykin was the inventor of the iconoscope and kinescope television systems. Theodosius Dobzhansky was the central figure in the field of evolutionary biology for his work in shaping the modern synthesis. George Gamow was one of the foremost advocates of the Big Bang theory. Many foreign scientists lived and worked in Russia for a long period, such as Leonard Euler and Alfred Nobel. Space exploration Roscosmos is Russia's national space agency. The country's achievements in the field of space technology and space exploration can be traced back to Konstantin Tsiolkovsky, the father of theoretical astronautics, whose works had inspired leading Soviet rocket engineers, such as Sergey Korolyov, Valentin Glushko, and many others who contributed to the success of the Soviet space program in the early stages of the Space Race and beyond. In 1957, the first Earth-orbiting artificial satellite, Sputnik 1, was launched. In 1961, the first human trip into space was successfully made by Yuri Gagarin. Many other Soviet and Russian space exploration records ensued. In 1963, Valentina Tereshkova became the first and youngest woman in space, having flown a solo mission on Vostok 6. In 1965, Alexei Leonov became the first human to conduct a spacewalk, exiting the space capsule during Voskhod 2. In 1957, Laika, a Soviet space dog, became the first animal to orbit the Earth, aboard Sputnik 2. In 1966, Luna 9 became the first spacecraft to achieve a survivable landing on a celestial body, the Moon. In 1968, Zond 5 brought the first Earthlings (two tortoises and other life forms) to circumnavigate the Moon. In 1970, Venera 7 became the first