|MadSci Network: Astronomy|
The first manmade object in space was the Sputnik 1 satellite. It was launched by the Soviet Union on October 4th, 1957. This came as a shock to the United States as they had not been aware that the Russians already had such a capability.
It orbited the Earth every 98 minutes. Using that information I calculate that its average speed in orbit was 25,000 miles/hour.
For More information check out the following links: