The RM-81 Agena was an American rocket upper stage and satellite bus which was developed by Lockheed Corporation initially for the canceled WS-117L reconnaissance satellite program. Following the split-up of WS-117L into SAMOS and Corona for image intelligence, and MIDAS for early warning, the Agena was later used as an upper stage, and an integrated component, for several programs, including Corona reconnaissance satellites and the Agena Target Vehicle used to demonstrate rendezvous and docking during Project Gemini. It was used as an upper stage on the Atlas, Thor, Thorad and Titan IIIB rockets, and considered for others including the Space Shuttle and Atlas V. A total of 365 Agena rockets were launched between February 28, 1959 and February 1987. Only 33 Agenas carried NASA payloads and the vast majority were for DoD programs.
BYEMAN codenamed GAMBIT, the KH-7 was a reconnaissance satellite used by the United States from July 1963 to June 1967. Like the older CORONA system, it acquired imagery intelligence by taking photographs and returning the undeveloped film to earth. It achieved a typical ground-resolution of 0.61 m to 0.91 m. Though most of the imagery from the KH-7 satellites was declassified in 2002, details of the satellite program remained classified until 2011.
Galactic Radiation and Background (GRAB) was the first successful United States orbital surveillance program, comprising a series of five Naval Research Laboratory electronic surveillance and solar astronomy satellites, launched from 1960 to 1962. Though only two of the five satellites made it into orbit, they returned a wealth of information on Soviet air defense radar capabilities as well as useful astronomical observations of the Sun.
The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was launched 109 times between 1960 and 1978. It was used to launch the first five Mariner uncrewed probes to the planets Venus and Mars, and the Ranger and Lunar Orbiter uncrewed probes to the Moon. The upper stage was also used as an uncrewed orbital target vehicle for the Gemini crewed spacecraft to practice rendezvous and docking. However, the launch vehicle family was originally developed for the Air Force and most of its launches were classified DoD payloads.
Thor was a US space launch vehicle derived from the PGM-17 Thor intermediate-range ballistic missile. The Thor rocket was the first member of the Delta rocket family of space launch vehicles. The last launch of a direct derivative of the Thor missile occurred in 2018 as the first stage of the final Delta II.
SOLRAD was an American series of satellites sponsored by the US Navy in a program to continuously monitor the Sun. SOLRAD was the Naval Research Laboratory's first post-Vanguard satellite.
OSO 7 or Orbiting Solar Observatory 7, before launch known as OSO H is the seventh in the series of American Orbiting Solar Observatory satellites launched by NASA between 1962 and 1975. OSO 7 was launched from Cape Kennedy on 29 September 1971 by a Delta N rocket into a 33.1° inclination, low-Earth orbit, and re-entered the Earth's atmosphere on 9 July 1974. It was built by the Ball Brothers Research Corporation (BBRC), now known as Ball Aerospace, in Boulder Colorado.
SOLRAD 4B was a solar X-ray, ultraviolet, and electronic surveillance satellite. Developed by the United States Navy's United States Naval Research Laboratory, it was the fifth in both the SOLRAD and the GRAB programs.
An X-ray astronomy satellite studies X-ray emissions from celestial objects, as part of a branch of space science known as X-ray astronomy. Satellites are needed because X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites.
The history of X-ray astronomy begins in the 1920s, with interest in short wave communications for the U.S. Navy. This was soon followed by extensive study of the earth's ionosphere. By 1927, interest in the detection of X-ray and ultraviolet (UV) radiation at high altitudes inspired researchers to launch Goddard's rockets into the upper atmosphere to support theoretical studies and data gathering. The first successful rocket flight equipped with instrumentation able to detect solar ultraviolet radiation occurred in 1946. X-ray solar studies began in 1949. By 1973 a solar instrument package orbited on Skylab providing significant solar data.
Discoverer 18, also known as Corona 9013, was an American optical reconnaissance satellite launched on 7 December 1960 at 20:24:00 GMT. It was the first successful, and the third of ten total Corona KH-2 satellites, based on the Agena-B.
OSCAR 3 is the third amateur radio satellite launched by Project OSCAR into Low Earth Orbit. OSCAR 3 was launched March 9, 1965 by a Thor-DM21 Agena D launcher from Vandenberg Air Force Base, Lompoc, California. The satellite, massing 15 kg (33 lb), was launched piggyback with seven United States Air Force satellites. Though the satellite's active life was limited to sixteen days due to battery failure, OSCAR 3 relayed 176 messages from 98 stations in North America and Europe during its 274 orbit life-time -- the first amateur satellite to relay signals from Earth. As of 2022, it is still in orbit.
Solrad 10, also known Explorer 44, NRL-PL 165 and Explorer SE-C, was one of the SOLRAD series designed to provide continuous coverage of wavelength and intensity changes in solar radiation in the UV, soft and hard X-ray regions. The satellite also mapped the celestial sphere using a high-sensitivity X-ray detector. Information collected was expected to contribute to a better understanding of the physical processes involved in solar flares and other solar activity, and the potential effects of this activity on short-wave communications, as well as on future human space travel. For the period of July 1971 to June 1973, the core memory data of Explorer 44 were used rather than those from Explorer 37. The Explorer 44 core memory failed on 11 June 1973, and Explorer 37 was heavily used until 25 February 1974, when the gas supply of the attitude control system was exhausted.
The Gravity Gradient Stabilization Experiment (GGSE-1) was a technology satellite launched simultaneously with four other satellites on 11 January 1964 by the U.S. military from Vandenberg Air Force Base aboard a Thor Augmented Delta-Agena D rocket. It demonstrated a new oscillation damping system intended for use in reconnaissance satellites.
SOLRAD 7A was the seventh solar X-Ray monitoring satellite in the SOLRAD series, and the fourth to successfully orbit the Earth. It was boosted into orbit along with four other military satellites atop a Thor Augmented Delta-Agena D rocket on January 11, 1964. Data returned by SOLRAD 7A dramatically revised scientific models of the solar corona.
SOLRAD1 is the public designation for SOLRAD/GRAB 1, a combination science and surveillance satellite launched into orbit on 22 June 1960. It was the first satellite to successfully observe solar X-rays, the first to conduct surveillance from orbit, and the first to be launched with another instrumented satellite.
SOLRAD 2 was the public designation for a combination surveillance and solar X-rays and ultraviolet scientific satellite, the second in the SOLRAD program developed by the United States Navy's Naval Research Laboratory. The SOLRAD scientific package aboard the satellite provided cover for the GRAB electronic surveillance package, the mission of which was to map the Soviet Union's air defense radar network.
SOLRAD 3 was a solar X-ray satellite, the third in the SOLRAD program. Developed by the United States Navy's Naval Research Laboratory (USNRL), it shared satellite space with and provided cover for the Navy's GRAB 2, a secret electronic surveillance program.
SOLRAD 4 was a solar X-rays, ultraviolet, and electronic surveillance satellite. Developed by the United States Navy's United States Naval Research Laboratory (USNRL), it was the fourth in both the SOLRAD and the GRAB programs.
SOLRAD 7B was the eighth solar X-Ray monitoring satellite in the SOLRAD series and the fifth to successfully orbit the Earth. It was launched via Thor Augmented Delta-Agena D along with seven other satellites on March 9, 1965. The satellite provided continuous coverage of the Sun during the International Quiet Solar Year from March through October 1965.
