Besides contributing to education, industry, and medicine, the space program has benefited communication. As a matter of fact, space satellites have revolutionized world communication. By 1960, the demand for overseas telephone and telegraph message for the United States was growing even faster. Industry could see no way to lay undersea cable. Transoceanic television was considered impractical. Satellites have changed all this. From thousands of kilometres above our earth, a communications satellite receives a signal from one side of the world and relays it directly to the other.
The first experiments with communications satellites were conducted in the early 1960s. Today about half the worlds long-distance telephone, telegraph, and television traffic is relayed by satellite. Through international agreements, the cost of transoceanic communication has cut almost in half.
An example of other ways in which satellites can benefit mankind was provided in 1970 by an international congress on post-graduate medical instruction. The American participants were in Texas; participating Europeans were in Switzerland, Germany, and Austria. For three hours by satellite, 30,000 doctors saw and heard their colleagues across the sea.
Satellites are being used not only for medical purposes and for education but also for predicting the weather in a more reliable way. Many lives have been saved by advance warnings of hurricanes and other dangerous storms. Before satellites, weather forecasters had information only from locations with observation stations. The information was generally available only from land areas. There were few reports about conditions in areas covered by oceans about three-fourths of the worlds surface. The significance of this lack becomes apparent with the realization that most bad weather originates at sea.
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