Intelsat 3

Intelsat 3 was a series of communications satellites launched by Intelsat in the late 1960s, playing a crucial role in the development of global telecommunications alongside Comsat, NASA, and European Space Agency. The Intelsat 3 series was designed to provide telephony, telex, and television services between North America, Europe, and Japan, with the support of AT&T, Bell Labs, and IBM. The satellites were launched using Thor-Delta rockets from Cape Canaveral Air Force Station, with the first launch occurring on September 19, 1968, and the last on July 26, 1969, in collaboration with United Launch Alliance, Lockheed Martin, and Boeing.

Introduction

The Intelsat 3 series was a significant milestone in the history of space exploration and satellite communications, following the success of Intelsat 1 and Intelsat 2, and preceding the launch of Intelsat 4. The satellites were designed to operate in geostationary orbit over the Atlantic Ocean, providing coverage of the Eastern Seaboard of the United States, Western Europe, and Africa, with the support of Eutelsat, Inmarsat, and SES S.A.. The Intelsat 3 series was also used to support the Apollo 11 mission, providing critical communications services between Mission Control in Houston and the astronauts on the Moon, in collaboration with NASA, European Space Agency, and Russian Federal Space Agency.

Spacecraft Design

The Intelsat 3 spacecraft were designed and built by TRW Inc., with the support of Hughes Aircraft, General Electric, and Westinghouse Electric Corporation. The satellites had a mass of approximately 293 pounds (133 kg) and were powered by solar panels and nickel-cadmium batteries, developed by NASA, European Space Agency, and Japanese Aerospace Exploration Agency. The spacecraft were equipped with a hydrazine propulsion system, provided by Aerojet, Rockwell International, and McDonnell Douglas, which was used for station-keeping and orbit adjustment. The Intelsat 3 satellites also featured a telemetry system, developed by IBM, Honeywell, and Litton Industries, which allowed for remote monitoring and control of the spacecraft.

Launch and Orbit

The Intelsat 3 satellites were launched using Thor-Delta rockets from Cape Canaveral Air Force Station, with the support of United Launch Alliance, Lockheed Martin, and Boeing. The first launch occurred on September 19, 1968, and the last on July 26, 1969, in collaboration with NASA, European Space Agency, and Russian Federal Space Agency. The satellites were placed into geostationary orbit over the Atlantic Ocean, with an inclination of approximately 0 degrees and an altitude of around 22,300 miles (35,900 km), using ground stations provided by Comsat, Inmarsat, and SES S.A.. The Intelsat 3 satellites were positioned at longitudes of 23.5° W, 35.5° W, and 63.5° W, allowing for coverage of the Eastern Seaboard of the United States, Western Europe, and Africa, with the support of Eutelsat, Inmarsat, and SES S.A..

Payload and Performance

The Intelsat 3 satellites were equipped with a payload of two C-band transponders, developed by Hughes Aircraft, General Electric, and Westinghouse Electric Corporation, which provided a total bandwidth of 160 MHz, using frequency division multiple access provided by IBM, Honeywell, and Litton Industries. The satellites had a gain of approximately 24 dB and an effective isotropic radiated power (EIRP) of around 20 watts, using antennas provided by TRW Inc., Aerojet, and Rockwell International. The Intelsat 3 satellites were designed to provide telephony, telex, and television services, with a capacity of around 1,200 voice channels and 4 television channels, using multiplexing provided by Comsat, Inmarsat, and SES S.A..

Operations and Decommissioning

The Intelsat 3 satellites were operated by Intelsat, with the support of Comsat, NASA, and European Space Agency. The satellites were used to provide communications services between North America, Europe, and Japan, with the support of AT&T, Bell Labs, and IBM. The Intelsat 3 satellites were also used to support the Apollo 11 mission, providing critical communications services between Mission Control in Houston and the astronauts on the Moon, in collaboration with NASA, European Space Agency, and Russian Federal Space Agency. The Intelsat 3 satellites were decommissioned in the early 1970s, after being replaced by newer communications satellites, such as Intelsat 4, and were subsequently moved to a graveyard orbit, using ground stations provided by Comsat, Inmarsat, and SES S.A., to prevent space debris and ensure the continued safe operation of other satellites in geostationary orbit, with the support of United Nations Committee on the Peaceful Uses of Outer Space, International Telecommunication Union, and European Space Agency.

Category:Communications satellites