The LM-700 is a

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 ...

which was built by

Lockheed Martin The Lockheed Martin Corporation is an American Arms industry, 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 ...

between the mid-1990s and early 2000s. Typically used for

low Earth orbit A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial object ...

communications satellites A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. ...

, ninety nine were built, all but one for

Iridium Satellite LLC Iridium Communications Inc. (formerly Iridium Satellite LLC) is a publicly traded American company headquartered in McLean, Virginia, United States. Iridium operates the Iridium satellite constellation, a system of 80 satellites: 66 are active ...

. The exception was a technology development satellite for the

United States Air Force The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...

, which was never launched. In addition, two boilerplate satellites were launched on a test flight of the

Chinese Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethnic ...

Long March 2C The Long March 2C (LM-2C), also known as the Chang Zheng 2C (CZ-2C), is a Chinese orbital launch vehicle, part of the Long March 2 rocket family. Developed and manufactured by the China Academy of Launch Vehicle Technology (CALT), the Long M ...

rocket.

Overview

Two variants of the LM-700 were built. The ninety eight Iridium satellites used the LM-700A configuration, specialised for communications. Of these ninety five were launched, whilst three were retained as spares. One of the spare satellites is now displayed in the US

National Air and Space Museum The National Air and Space Museum (NASM) of the Smithsonian Institution is a museum in Washington, D.C., in the United States, dedicated to history of aviation, human flight and space exploration. Established in 1946 as the National Air Museum, ...

. The LM-700B, designed for other missions, was also offered. One was built as the SBIRS-LADS demonstration satellite for the US Air Force's

Space Based Infrared System The Space-Based Infrared System (SBIRS) is a United States Space Force system intended to meet the United States' Department of Defense infrared space surveillance needs through the first two to three decades of the 21st century. The SBIRS prog ...

, however its launch was cancelled after the satellite had been completed and delivered to the customer. The LM-700A Iridium satellites were launched in clusters between 1997 and 2002. Satellites were launched in groups of five on

Delta II Delta II was an expendable launch system, originally designed and built by McDonnell Douglas, and sometimes known as the Thorad Delta 1. Delta II was part of the Delta rocket family, derived directly from the Delta 3000, and entered service in ...

7920-10C rockets, groups of seven on

Proton-K The Proton-K, also designated Proton 8K82K after its GRAU index or SL-12 after its model number, was a Russian, previously Soviet, carrier rocket derived from the earlier Proton. It was built by Khrunichev, and launched from sites 81/23, 8 ...

/ DM2 rockets, pairs on the Long March 2C and on the last launch, two satellites on a

Rockot Rokot ( meaning ''Rumble'' or ''Boom''), also transliterated Rockot, was a Soviet Union (later Russian) space launch vehicle that was capable of launching a payload of into a Earth orbit with 63° inclination. It was based on the UR-100N (S ...

. The cancelled SBIRS-LADS satellite would have used an

Athena II The Athena II is an American small expendable launch system which was used for three launches between 1998 and 1999, and which was scheduled to return to service in 2012 but has not been flown again as of 2024. It is a member of the Athena family ...

. An LM-700A,

Iridium 33 Iridium 33 was a communications satellite launched by Russia for Iridium Communications. It was launched into low Earth orbit from Site 81/23 at the Baikonur Cosmodrome at 01:36 UTC on 14 September 1997, by a Proton-K rocket with a Block DM2 u ...

was one of the satellites destroyed in the

2009 satellite collision On February 10, 2009, two communications satellites—the active commercial Iridium 33 and the derelict Russian military Kosmos 2251—accidentally collided at a speed of and an altitude of above the Taymyr Peninsula in Siberia. It was the f ...

. Most of the Iridium satellites currently in orbit have already exceeded their design life, whilst others are approaching the end of it, however at least enough satellites are still operating to maintain the

network Network, networking and networked may refer to: Science and technology * Network theory, the study of graphs as a representation of relations between discrete objects * Network science, an academic field that studies complex networks Mathematics ...

, which requires sixty six.

Satellites

References

* * * * * {{reflist Satellite buses

Overview

Satellites

See also

References