On April 12, Russia celebrates the World Aviation and Astronautics Day, established by the decree of the Presidium of the Supreme Soviet of the USSR of April 9, 1962 in honor of the first human flight in space, performed by the Soviet Union citizen Yuri Alekseevich Gagarin aboard Vostok1 spacecraft on April 12, 1961. A solemn gathering and laying flowers at the Memorial Plaque in Honor of the Pilot-Cosmonaut twice Hero of the Soviet Union Georgy Mikhailovich Grechko and the Pilot-Cosmonaut Hero of the Russian Federation Andrey Ivanovich Borisenko took place in the building of the SPC RAS.