when did the u.s.s.r launch the first satellite to orbit the world
Sputnik 1 Sputnik 1 (/ˈspʌtnɪk/; "Satellite-1", or "PS-1", Prosteyshiy Sputnik-1, "Elementary Satellite 1")[5] was the first artificial Earth satellite. The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957. It was a 58 cm (23 in) diameter polished metal sphere, with four external radio antennas to broadcast radio pulses. It was visible all around the Earth and its radio pulses were detectable. This surprise success precipitated the American Sputnik crisis and triggered the Space Race, a part of the Cold War. The launch ushered in new political, military, technological, and scientific developments.[6][7]