putnik is the Soviet word for traveling companion, and Sputnik 1 was the first space traveler from Earth. The world’s first artificial satellite, it was launched by the Soviet Union on October 4, 1957.
International Geophysical Year
After World War II brought advances in rocket technology, interest in launching artificial satellites grew, in both the United States and the Soviet Union. The world’s science organizations designated 1957 to 1958 as International Geophysical Year. Committees were formed to observe such phenomena as cosmic rays, gravity, and solar activity. It was hoped that the period also would see the launch of the first satellite.
The United States prepared two satellites, Explorer and the smaller Vanguard. No one was entirely sure that a satellite launch would work. For that reason, Vanguard was a tiny spacecraft, designed to test the theory that it was
possible to launch a satellite on top of a multistage rocket. Unlike the Soviets, the Americans had relatively small launch rockets. Also unlike the Soviets, they released details of their space program to the public.
Very little information had been released about Soviet space plans, although some details of space radio links had been made public, suggesting that the Soviets had a satellite program. This was the era of the Cold War, when the United States and the Soviet Union were building up their supplies of large rockets for military use as well as for scientific study. Rockets used as ballistic missiles could potentially deliver nuclear weapons over ranges of thousands of miles. Both sides kept their military developments secret, and the Soviet Union extended this secrecy to its development of space technology.
The satellite Sputnik 1 was fairly simple. It was an aluminum sphere pressurized by nitrogen gas. Inside the sphere were batteries providing electrical power for two radio transmitters. Attached to the outside of the sphere were four whip-like radio antennae.
Launch date: October 4, 1957.
Size: 23 inches (58 centimeters) in diameter.
Weight: 183 pounds (83 kilgrams). Speed: About 18,000 miles per hour (28,960 kilometers per hour).
Orbital height: 143-584 miles (230-940 kilometers).
Orbital time: 96 minutes.