The Space Age started on October 4, 1957, when Russia launched the satellite Sputnik 1. A satellite is anything that orbits a planet. For instance, the Moon is a satellite of the Earth.
But Sputnik 1 was the first artificial satellite to orbit the Earth — its name is Russian for “traveling companion.”
Sputnik 1 was a metal sphere about the size of a beach ball, with four antennae, each approximately 2.6 m (8.5 ft.) long. It could transmit radio signals back to Earth.
On December 19, 1958, the United States launched Project SCORE (Signal Communication by Orbiting Relay Equipment), the world’s first communications satellite. Probably the most important thing communications satellites have done is make international phone calls — especially in remote areas — possible and inexpensive.
Satellite technology evolved a lot in the next decades and changed how people communicated. It also changed how TV and radio were broadcast and much more.
Satellites are used in weather forecasting, video conferencing, long-distance learning, navigation and military applications. People in remote areas rely on satellites for their Internet connections.
Space exploration satellites, or space probes, send back detailed images and other information about space. The data they’ve sent back have led to many important discoveries, including the rings of Jupiter.