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.
Learn about three ways that satellites have led to a better understanding of how we affect our environment.
Telstar was one of the most significant communications satellites of the early space age. It raised an important policy question: Should communications satellites be operated and controlled by private corporations or under government auspices? The United States chose government direction and created two new institutions, COMSAT and INTELSAT, to develop satellite communcations, an arrangement ...
This satellite represents the first generation of space-based, commercial radio service developed by Sirius Radio, a U.S. company (now Sirius XM Radio). Designed in 1987 and initiating service in 2001, the Sirius satellite system consisted of three satellites that provided more than 150 digital music and audio channels to North America. Their inclined geosynchronous orbits were a distinctive ...
Today, hundreds of civilian and military applications satellites ring the Earth, often operating side-by-side in orbit. They provide similar services—communications, photography, remote sensing, weather analysis, and navigation—reaching different but occasionally overlapping communities of users. These satellites have become an integral part of contemporary life. We take for granted daily ...
Earth's natural satellite is the Moon, but many objects in our Solar System have multiple natural satellites. Humans have also created artificial satellites—human-made machines and spacecraft in orbit around our Earth or other objects in our galaxy.
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 ...