Sputnik 1, Earth's First Artificial Satellite (Photos)

The 183-pound (83-kilogram) spacecraft whipped around the Earth every 98 minutes, transmitting a series of beeps.

A Soviet technician works on Sputnik 1 before the satellite’s Oct. 4, 1957 launch.

Sputnik was in the form of a sphere, 23 inches (58 centimeters) in diameter and pressurized with nitrogen.

Four radio antennas trailed behind the spacecraft’s spherical body. These ensured that the satellite transmitted radio signals equally in all directions regardless of its rotation. Two of them were 7.9 feet (2.4 meters) long, and the other two were 9.5 feet (2.9 meters) long.

Soviet scientist Leonid Sedov, who created the Sputnik 1, helps to cut a rocket-shaped cake at the International Astronautical Conference in Barcelona a few days after the satellite launched in October of 1957.

The Sputnik 1 satellite launched on a rocket of a similar name: Sputnik-PS.

Sputnik 1 launched from the Baikonur Cosmodrome in Kazakhstan on Oct. 4, 1957.

The launch of Sputnik 1 didn’t go entirely to plan. Because the booster didn’t reach full power during liftoff, Sputnik ended up orbiting about 310 miles (500 km) lower than it was designed to go.

Sputnik 1 orbited the Earth for 21 days, circling around the globe every 96.2 minutes. The orbit of Sputnik 1 is traced on globe designed by NASA engineer Robert Farquhar.

The Sputnik 8K71PS rocket streaks across the sky over Montreal on its way to deliver Sputnik 1 into orbit.

Scientists from the California Institute of Technology track Sputnik 1 from a mobile van.

Radio signals from Sputnik 1 are measured at a radio control post near Moscow as radio operators listen for the characteristic “beep-beep-beep” coming from the satellite.

Students of the Moscow Electrotechnical Institute communicate with their American colleagues via ham radio to discuss signals received from Sputnik 1.

Staff at the Central Astronomical Observatory of the Ukrainian Academy of Sciences in Kiev prepare to conduct optical observations of the Sputnik 1 satellite.

Amateur radio operator Dick Oberholtzer and his wife Ruth listen to radio signals from Sputnik 1 via ham radio in Elm Grove, Wisconsin.

Electronics engineers at the 1957 National Electronics Conference in Chicago set up equipment to listen for signals from Sputnik 1.

An oscilloscope reading shows a signal received from Sputnik 1.

The front page of the New York Daily News on Oct. 5, 1957 — one day after Sputnik 1 launched — details the first sighting of the satellite over the United States. It reads, “The Russian satellite was seen for the first time in the U.S. tonight at Columbus, Ohio where Larry Ochs, manning a Moonwatch observation station, reported sighting a steady light that crossed his telescope. It was definitely not a meteor, he said.”

An Albanian postage stamp commemorates the a Soviet Sputnik satellite. (“Shqipëria” is another name for Albania.)

These young students on a guided tour of United Nations Headquarters in New York City check out a model of the Sputnik 1. The Sputnik model was presented to the United Nations as a gift from the Soviet Union.

A Sputnik replica hangs on display in the Milestones of Flight at the Smithsonian’s National Air and Space Museum in Washington, D.C.

Visitors at the Chabot Space and Science Center in Oakland, California can view a replica of Sputnik 1 and other space artifacts.