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100th Anniversary Logo with the 100 in large letters and the museum logo
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Sputnik I

The space age began on Oct. 4, 1957, when the Soviet Union launched Sputnik I, the first artificial earth satellite. The event was a milestone in space exploration and a defining moment of the Cold War. It caused great anxiety in the United States because the public equated space achievements with military and technological power. To many, Sputnik represented the threat of superior Soviet space and missile technology.

Sputnik, which means "satellite" in Russian, was the Soviet entry in a scientific race to launch the first satellite. In 1954 the International Council of Scientific Unions urged governments to design, build and launch earth-mapping satellites during the "International Geophysical Year" (IGY), planned for 1957-1958. Both the United States and the USSR announced they would orbit satellites. The IGY was an opportunity for both the USSR and the United States to demonstrate world leadership in space and rocket technology -- and though the IGY focused on international cooperation and the peaceful use of space, satellites and rockets had obvious military implications. 

In the fall of 1957, the Russians feared that an American satellite, called Vanguard, would be ready before theirs. The Soviets abandoned plans to launch a complex satellite featuring many scientific instruments and instead quickly built the simplest satellite possible -- Sputnik I -- to launch first. Sputnik was conceived, built and launched in about a month. Its launch vehicle was a Soviet intercontinental ballistic missile, and the satellite circled the earth for three months before falling from orbit. Sputnik's success was a propaganda victory for the Soviet Union.

Disturbed by Russian success and disorganized American rocket development, the Eisenhower administration created NASA in 1958 as an outgrowth of the National Advisory Committee for Aeronautics (NACA). NASA's mission was to manage civilian space exploration and retake the lead in the Cold War technology race. The U.S. military, already at work planning satellite programs, redoubled its efforts. About four months after Sputnik's great success and a series of embarrassing American failures, the U.S. finally launched its first satellite, Explorer I, on Jan. 31, 1958.

183 lbs.
Equipment: Three silver-zinc batteries, two D-200 radio transmitters, pressure and temperature transmitters, DTK-34 temperature control system
Launch vehicle: R-7 intercontinental ballistic missile variant
Orbital period: 96.17 min.
Apogee: 588 miles
Perigee: 142 miles
Orbital inclination: 65.6 degrees to equator

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Find Out More
Wes Henry: "50th Anniversary of the Space Age" (00:50:19)
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