Inmarsat-3 F4 is a communications satellite operated by the British satellite operator

Inmarsat Inmarsat is a British communications satellite, satellite telecommunications company, offering global mobile services. It provides telephone and data services to users worldwide, via portable or mobile terminals which communicate with groun ...

. It was launched into a

geosynchronous orbit A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital ...

on 4 June 1997 from the

Guiana Space Centre The Guiana Space Centre (; CSG), also called Europe's Spaceport, is a spaceport to the northwest of Kourou in French Guiana, an Overseas departments and regions of France, overseas region of France in South America. Kourou is located approxim ...

in Kourou, French Guiana. It was located at 54° West longitude whilst in service, providing coverage of the Americas as Atlantic Ocean Region-West (AOR-W). It was replaced by Inmarsat-3 F5 at 54° West in February 2016, and the now retired Inmarsat-3 F4 was moved to parking at 144° West. The Inmarsat 3 series spacecraft (F1 thru F5) were built by

Lockheed-Martin The Lockheed Martin Corporation is an American defense and aerospace manufacturer with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta on March 15, 1995. It is headquartered in North Bethesda, Mary ...

Astro Space as the prime contractor.

was responsible for the basic spacecraft bus, and the European

Matra Marconi Space Matra Marconi Space (MMS) was a Franco-British aerospace company. History Matra Marconi Space was established in 1990 as a joint venture between the space and telecommunication division of the French conglomerate Matra (Matra Espace) and ...

, developed the advanced communications payload. The Inmarsat 3 communications payload can generate a global beam and a maximum of seven spotbeams. The spotbeams are directed as required to make extra communications capacity available in areas where demand from users is high. The spacecraft was built using an AS-4000

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

. It has a mass of , and is expected to operate for 13 years. In the United States, Inmarsat ground stations are licensed to operate at 1525-1559

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base u ...

and 1626.5-1660.5 MHz via a mechanism called the ISAT List. The 1544-1545 MHz and 1645.5-1646.5 MHz bands are reserved for safety and distress communications. RobSA1

References

External links

Our Satellites - Inmarsat
* http://www.boeing.com/news/releases/2005/q4/nr_051108s.html * http://www.as.northropgrumman.com/products/aa_inmarsat/index.html {{Orbital launches in 1997 Spacecraft launched in 1997 Communications satellites in geostationary orbit Inmarsat satellites

See also

References

External links