The Vostok rocket was developed by the Soviet Union to as their main launch vehicle for space flights. It was based on the R-7, an ICBM designed by Sergei Korolev and first launched in 1957. An R-7 rocket was used to carry Sputnik 1 into space on October 4, 1957. It was a single rocket with 4 booster engines attached to the sides, which acted like a multi stage rocket. The Vostok was an R-7 with an extra upper stage rocket, called Blok-E. This upper stage would fire as the lower stages ran out of fuel (a mix of kerosene and liquid oxygen.