Sputnik 1

Sputnik 1 was Earth's first artificial satellite, launched into orbit on October 4, 1957 via simple liquid oxygen/liquid hydrogen rockets. The name "Sputnik", from Earth's Russian language, is generally translated as "fellow traveller".

The launch of Sputnik was a major event in Earth's "Cold War" period in the second half of the 20th century, since any nation that posessed rockets which could launch payloads into orbit could drop bombs anywhere on the planet.

"Sputnik" on Wikipedia