Communications Satellites
Think about the last time you sent a text, made a call, or binged through the latest season of your favorite show. Have you ever thought about the technology that put all these resources at our fingertips? Communications satellites are one such technology, and they play a major role in our daily lives.
Prior to the 1960s, long-distance communication via radio, telephone, and television networks was a challenge. Local areas often had very good coverage, and broad networks might blanket a nation, but the whole world wasn't yet covered. The existing technology—including undersea telegraph cables and radio and television receivers and reflector—had limits in reaching distant places, especially across oceans. The result: communications were slower, shorter-range, and lower quality than we're used to today.
Pictured: Before satellites sent us news and music from far away, people used shortwave radios, like this RCA model 6Q1 made in ca. 1940. They received “shortwaves” that bounced off Earth’s atmosphere. This technique was often unreliable but did allow communications with other continents.
Object Highlight
SCORE Communications Satellite
In 1958, President Dwight D. Eisenhower used SCORE—the first communication satellite—to broadcast a Christmas message: "Through this unique means I convey to you and all mankind, America's wish for peace on Earth and goodwill toward men everywhere."
The SCORE (Signal Communications by Orbital Relay Equipment) satellite operated for 35 days. It proved that satellites could receive signals from one location on Earth and immediately retransmit them to another, as well as receive a signal, store it on an onboard recorder, and then transmit on command from the ground. These technical accomplishments provided the basis for future communications satellites.
The artifact seen here is a backup payload from the Museum's collection.
Communications Satellites Close the Gaps
By the mid-1960s, communications satellites had become reliable tools. Satellites positioned in high orbits could "see" large swaths of Earth, allowing them to receive and send signals from distant places. Satellites brought radical change, filling in communication gaps and providing telephone and television connection nearly worldwide. Television could now provide hundreds of millions of people cross the globe with ground-breaking news and images. Soon the tagline "live via satellite" became a staple of TV viewing. Pictured: An Intelsat II Communications Satellite flight spare from the Museum's collection.
Most communications satellites have the same basic components, pointed out in this diagram:
- Solar cells and batteries to power the satellite systems
- Antennas to receive and transmit signals
- Transponder to alter the frequency of incoming signals (avoiding interference with outgoing signals) and to amplify signals before transmitting them back to Earth
- Orientation and propulsion systems to keep the antennas pointed at Earth, and the satellite in the right orbit.
Satellites Change How We Experience Historical Moments
Satellites Change How We Experience Historical Moments
With the invention of things like airplanes and jet engines, our understanding of the planet shifted: Earth was becoming one connected planet—one global neighborhood. Communications satellites played a major role in this shift.