Intelsat 603 or IS-603, previously named Intelsat VI F-3, is a

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

operated by

Intelsat Intelsat S.A. (formerly Intel-Sat, Intelsat) is a Luxembourgish-American multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons, Virginia, United States. Originally formed ...

. Launched in 1990, it was the second of five Intelsat VI satellites to be launched. The Intelsat VI series was constructed by

Hughes Aircraft The Hughes Aircraft Company was a major American aerospace company, aerospace and defense contractor founded on February 14, 1934 by Howard Hughes in Glendale, California, as a division of the Hughes Tool Company. The company produced the Hughes ...

, based on the HS-389

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 ...

Launch

Intelsat 603 was launched at 11:52:31 UTC on 14 March 1990, atop a

Commercial Titan III The Commercial Titan III, also known as CT-3 or CT-III, was an American expendable launch system, developed by Martin Marietta during the late 1980s and flown four times during the early 1990s. It was derived from the Titan 34D, and was originall ...

carrier rocket, flight number CT-2, with an Orbus-21S upper stage. The launch took place from Launch Complex 40 at the

Cape Canaveral Air Force Station Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the sta ...

, and was intended to place Intelsat 603 into a

geosynchronous transfer orbit In space mission design, a geostationary transfer orbit (GTO) or geosynchronous transfer orbit is a highly elliptical type of geocentric orbit, usually with a perigee as low as low Earth orbit (LEO) and an apogee as high as geostationary orbit ...

. The Orbus-21S failed to separate from the Titan's second stage, and as a result it was unable to fire, leaving Intelsat 603 in

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 ...

. Following the launch failure, Intelsat commissioned

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

to launch a replacement perigee motor to raise the satellite's orbit. During its maiden flight,

STS-49 STS-49 was NASA's maiden flight of the Space Shuttle ''Endeavour'', which launched on May 7, 1992. The primary goal of its nine-day mission was to retrieve an Intelsat VI satellite, Intelsat 603, which failed to leave Low Earth orbit two yea ...

, in 1992 rendezvoused with and captured Intelsat 603, and astronauts attached a new Orbus-21S to the satellite. This motor successfully raised the satellite into the planned transfer orbit. The satellite raised itself into its final

geostationary orbit A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular orbit, circular geosynchronous or ...

using two liquid-fuelled R-4D-12 engines, with the satellite arriving in geostationary orbit on 21 May 1992.

Operations

Intelsat 603 operated in a geostationary orbit with a

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of , an

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

of , and 0.3 degrees of

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

. The satellite carried 38 IEEE C band and ten IEEE

transponder In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

s, and had a design life of 13 years and a mass of . Upon arrival in geostationary orbit, Intelsat 603 was placed at a longitude of 34.5 degrees west. It remained there until October 1997, when it was moved to 24.5 degrees west, arriving in November. In August 2002 it was relocated to 19.95 degrees west, where it operated until March 2010. Finally from May 2010 it operated at 11.5 degrees east until it was removed from geostationary orbit in January 2013. Intelsat confirmed in February 2015 that Intelsat 603 had been retired to a

graveyard orbit A graveyard orbit, also called a junk orbit or disposal orbit, is an Orbit (physics), orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellit ...

References

{{Orbital launches in 1990 Intelsat satellites Spacecraft launched in 1990 Spacecraft decommissioned in 2013 Spacecraft launched by Titan rockets Derelict satellites orbiting Earth