Titan IV was a family of heavy-lift space launch vehicles developed by Martin Marietta and operated by the United States Air Force from 1989 to 2005.
Lockheed Martin's Space Division started in the production of missiles and later ICBM's in the 1950s. Their TITAN missile system was used for 12 Gemini spacecraft and the Voyager probes. They have worked largely in collaboration with NASA on many of their probes, landers, and spacecraft, and hope to play a key role in NASA's return to the moon in 2024.
Satellite Data System (SDS) spacecraft are communication relay satellites for transmiting real-time data from US reconnaissance satellites (e.g. KH-11) in polar areas. They are also used for communications to USAF air craft on polar routes and connect the various ground stations of the Air Force Satellite Control Network (AFSCN). The spacecraft relay the downlinked KH-11 data to a ground station at Fort Belvoir, Virginia.
Elliptical Orbit