Sputnik

Today, 50 years ago, the world's first artificial satellite - the Sputnik - was launched from the Baikonur Cosmodrome in the Soviet Union. The Sputnik, meaning 'fellow traveler,' was unmanned, weighed 183 lbs. and circled the globe every 96 minutes. The satellite travelled at 18,000 miles per hour and emitted radio signals which were monitored by Amateur radio operators throughout the world.

The signals continued for 22 days until the transmitter batteries ran out on October 26, 1957. In early 1958, Sputnik burned as it fell from orbit upon reentering Earth's atmosphere, after traveling about 37 million miles in orbit.