The USSR launched Sputnik on October 4th, 1957 and Explorer 1 was launched on January 31st, 1958--so the answer is 119 days.
October 4, 1957 was the date when the Soviet Union successfully launched Sputnik I.
Sputnik 1 was launched on the 4th of October, 1957. The booster used by it had been used in August of that year to launch a long range missile.
The USSR launched Sputnik I, the first successful artificial satellite, on October 4, 1957.
Sputnik 1 was lauched on October 4 1957 by Russia.
Sputnik 1 was launched on the 4th of October 1957.
Sputnik 1, launched by the USSR (Russia) on October 4, 1957, was the first artificial satellite to successfully achieve Earth orbit. There had been several previous unsuccessful attempts by the USSR and the USA.
Sputnik I was launched by the USSR on October 4, 1957.
Sputnik 1, launched at 4 October 1957.
Sputnik 1 was launched October 4th, 1957.
Sputnik-1 was launched into orbit on October 4, 1957.
The Russians launched Sputnik 1 on the 4th October 1957, 7:28 PM.
Sputnik I was launched from the USSR on October 4, 1957.
Dwight D. Eisenhower was the President when the Soviet Union launched Sputnik on October 4, 1957.
Sputnik 1. It was launched on the 4th of October, 1957
Sputnik 1 was launched on 4 October 1957.
The first satellite was Sputnik 1, launched by the Russians on October 4th 1957.