![]() An Atlas-Agena launching Lunar Orbiter 4 | |
Function | Expendable launch system |
---|---|
Manufacturer | Convair General Dynamics |
Country of origin | United States |
Size | |
Height | 118.0 feet (36.0 m) |
Diameter | 10.0 feet (3.0 m) |
Width | 16.0 feet (4.9 m) |
Mass | 341,000 pounds (155,000 kg) |
Stages | 2½ |
Capacity | |
Payload to LEO | |
Mass | 2,200 pounds (1,000 kg) |
Payload to GEO | |
Mass | 1,540 pounds (700 kg) |
Payload to TLI | |
Mass | 850 pounds (390 kg) |
Payload to escape | |
Mass | 575 pounds (261 kg) |
Launch history | |
Status | Retired |
Launch sites | LC-12,13 &14,CCAFS SLC-3 &4,Vandenberg |
Total launches | 109 |
Success(es) | 93 |
Failure(s) | 13 |
Partial failure(s) | 3 |
First flight | 26 February 1960 |
Last flight | 27 June 1978 |
Boosters | |
No. boosters | 1 |
Width | 16.0 feet (4.9 m) |
Powered by | 2 |
Maximum thrust | 233,000 pounds-force (1,040 kN) |
Burn time | 134 seconds |
Propellant | RP-1/LOX |
First stage | |
Diameter | 10.0 feet (3.0 m) |
Powered by | 1 |
Maximum thrust | 67,000 pounds-force (300 kN) |
Burn time | 5 minutes |
Propellant | RP-1/LOX |
Second stage –Agena D | |
Height | 248 inches (6.3 m) |
Diameter | 5.0 feet (1.5 m) |
Powered by | 1 Bell Aerospace 8247 |
Maximum thrust | 16,000 pounds-force (71 kN) |
Burn time | 265 seconds |
Propellant | UDMH/IRFNA |
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. [1] 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.
The Atlas-Agena was a two-and-a-half-stage rocket,with a stage-and-a-half Atlas missile as the first stage,and an RM-81 Agena second stage. Initially,Atlas D missiles,redesignated as the LV-3,were used as the first stage. [2] These were later replaced by the standardized Atlas SLV-3,and its derivatives,the SLV-3A and B. The final Atlas-Agena launch used an Atlas E/F.
Launches were conducted from Launch Complexes 12,13 and 14 at the Cape Canaveral Air Force Station,and Launch Complexes 1 and 2 at Point Arguello (now SLC-3 and 4 at Vandenberg Air Force Base).
The earliest Agena variant was the Agena A in 1959–60,which did not have restart capability,mostly flown on Thor-Agena boosters for the Discoverer program.
The early Atlas LV3 Agena A variant was flown four times for the Midas and Samos programs (Midas 1,Midas 2,Samos 1,and Samos 2),with two failures.
Late in 1960,Lockheed introduced the uprated Agena B stage which was restartable and had longer propellant tanks for more burn time. It first flew on the Thor and did not make its maiden voyage on an Atlas for months,when Midas 3 launched on July 12,1961.
The Atlas LV-3 Agena B was used between 1961 and 1965 for a variety of NASA and DoD programs,including Ranger,Mariner,Samos,and Midas but proved a unreliable,with only 21 successes in 28 flights.
In late 1962,after Ranger 5 suffered a booster malfunction,albeit a minor one that ground controllers were able to work around,NASA convened a review board which undertook a wholesale reevaluation of the Atlas-Agena as a launch vehicle. The board found that quality control and checkout procedures were poor,and that this situation was exacerbated by the several dozen configurations of the booster,as each individual DoD and NASA program necessitated custom modifications to the Atlas and Agena,and the latter also differed in its Atlas and Thor variants. The board recommended improved quality control,better hardware,and also establishing one standardized launch vehicle for all space programs.
The result was the Atlas LV-3 Agena D,a standardized version of the Atlas D core and Agena B which would be the same on every launch (at least as far as the Atlas was concerned,Agena Ds often still had customized setups,especially for DoD payloads). The Agena D first flew in July 1963,starting a series of 15 successful launches for NASA and Air Force programs,including Ranger,Mariner,Midas,and Gambit.
The Atlas SLV-3 Agena D first flew in August 1964. Forty-seven Atlas SLV-3 Agena D boosters were flown over the following years,mostly for the KH-7 Gambit and Vela programs,and also for a few NASA missions like Mariner. +
The Atlas SLV-3B Agena-D was a specific variant used to launch the first OAO satellite in 1966.
The Atlas SLV-3 Agena-B was a specific variant used to launch the OGO-3 satellite in 1966.
The Atlas SLV-3A Agena-D was a variant with a extended tank,for twelve launches including OGO-5 and Canyon/Rhyolite SIGINT satellites,between 1968 and 1978.
The last Atlas-Agena was flown in 1978 to launch SEASAT,on a repurposed Atlas F missile designated Atlas E/F Agena D.
Name | First launch | Last launch | Launches | Successes | Failures | Partial failures | Remarks |
---|---|---|---|---|---|---|---|
Atlas LV-3 Agena-A | 1960-02-26 | 1961-01-31 | 4 | 2 | 2 | 0 | Early Atlas-Agena variant flown four times for the Midas and Samos programs |
Atlas LV-3 Agena-B | 1961-07-12 | 1965-03-21 | 28 | 21 | 5 | 2 | Enhanced,restartable Agena. Used for a variety of NASA and Air Force programs,including Ranger,Mariner,Samos,and Midas. |
Atlas LV-3 Agena-D | 1963-07-12 | 1965-07-20 | 15 | 15 | 0 | 0 | Standardized Agena B used for a variety of NASA and Air Force programs,including Ranger,Mariner,Midas,and Gambit. |
Atlas SLV-3 Agena-D | 1964-08-14 | 1967-11-05 | 47 | 41 | 5 | 1 | Standardized SLV-3 Atlas+Agena D used for a variety of NASA and Air Force programs,including Mariner,Vela,and Gambit. |
Atlas SLV-3B Agena-D | 1966-04-08 | 1 | 1 | 0 | 0 | One-off Atlas variant used for the first OAO satellite. | |
Atlas SLV-3 Agena-B | 1966-06-07 | 1 | 1 | 0 | 0 | One-off Atlas variant used for OGO-3 | |
Atlas SLV-3A Agena-D | 1968-03-04 | 1978-04-08 | 12 | 11 | 1 | 0 | Extended tank Atlas. Used for OGO-5 and Canyon/Rhyolite SIGINT satellites. |
Atlas E/F Agena D | 1978-06-27 | 1 | 1 | 0 | 0 | One-off Atlas variant mating the last Agena stage flown to a refurbished Atlas F missile for the launch of Seasat. | |
Included on Atlas-Agena vehicles was the Inadvertent Separation Destruct System (ISDS) to destroy the Agena in the event that it separated prematurely from the Atlas,a situation that could be caused by a booster hard-over or if the Atlas self-destructed in flight. The ISDS charges were mounted on the adapter section between the two vehicles and would activate if a series of tripwires were broken. During the coasting period between staging,the ISDS charges were disabled. It was also wired to the Atlas's own FTS (Flight Termination System) and would be activated if a destruct command was sent to the Atlas. The Agena could also have a separate FTS for use after the Atlas portion of the launch,although NASA planetary probes omitted them for weight-saving reasons and due to the flight trajectory used,which meant that destruct of the Agena was no longer possible following staging.
The Gemini-Agena Target Vehicle had a specially modified Range Safety destruct system designed to fire slugs into the propellant tanks rather than the conventional method of rupturing them externally,since an inadvertent activation in orbit could endanger the Gemini astronauts.
The very first Atlas-Agena flight,Midas 1 in February 1960,failed when the unproven ISDS system mistakenly activated at staging,rupturing the Atlas's LOX tank and causing the breakup of the Agena. The ISDS system was redesigned afterwards and this failure mode did not repeat itself. Two Atlas-Agena vehicles (Mariner 1 and Canyon 4) were intentionally destroyed when the Atlas went off-course and two others (MIDAS 6 and MIDAS 8) broke up in flight resulting in activation of the ISDS and destruct of the Agena.
The Ranger spacecraft were designed to impact the Moon, returning photographs of the lunar surface until their destruction. The spacecraft was designed in three Blocks, all similar in appearance with a forward antenna and magnetometer, supported by a boom, with more sensors and two solar panels and a dish antenna mounted at the base. The first two Block I spacecraft, Ranger 1 and Ranger 2, were launched on August 23 and November 18, 1961, not to the Moon, but in intended high Earth orbits to test the Atlas-Agena and spacecraft capabilities. However, the Agena malfunctioned on both flights and left the probes trapped in a useless low Earth orbit from which they soon decayed.
The Block II missions, Ranger 3, Ranger 4, and Ranger 5, were launched away from Earth in January, April, and October 1962, but all three failed due to either malfunctions of the probe or launch vehicle difficulties. Ranger 3 missed the Moon entirely. Ranger 4's solar panels failed to deploy, and the navigation system failed, sending the probe to impact the lunar far side without returning any pictures or data. Ranger 5 suffered an unknown failure which deprived it of power, and it missed the Moon by 725 kilometers (391 nautical miles).
Ranger 6, launched January 30, 1964, successfully impacted the Moon but its cameras failed to return pictures. The last three Rangers were finally successful: Ranger 7 in July 1964, Ranger 8 in February 1965, and Ranger 9 in March 1965.
The Mariner spacecraft were built by NASA's Jet Propulsion Laboratory. Mariner 1 and Mariner 2 were twins, launched on July 22 and August 27, 1962, to fly by the planet Venus. The first two craft used the same spacecraft bus as the Block I Rangers, each weighing 446 pounds (202 kg) and instrumented to perform radiometric temperature measurements of the planet, and to measure interplanetary magnetic fields and particles. [3] [4] Mariner 1's Atlas-Agena malfunctioned and went off course, requiring its destruction approximately 5 minutes after liftoff. Mariner 2 successfully made the 3½-month flight, becoming the first spacecraft to fly by another planet. It carried microwave and infrared radiometers, and sensors for cosmic dust, solar plasma and high-energy radiation, and magnetic fields.
Mariner 3 and Mariner 4 used a redesigned spacecraft bus weighing 575 pounds (261 kg), and were launched on November 5 and November 28, 1964, to fly by the planet Mars. Mariner 3 failed after a successful launch when its payload shroud failed to open. These Mariners carried cameras, and Mariner 4 successfully returned pictures of Mars as it flew by.
The 540-pound (240 kg) Mariner 5 was successfully launched to Venus on June 14, 1967, and flew by in October, probing Venus's atmosphere with radio waves, scanning its brightness in ultraviolet light, and sampling solar particles and magnetic field fluctuations above the planet.
The Agena rocket stage was used as the passive docking target for the Gemini crewed space program. After docking, the Agena could also be fired by the astronauts to raise the combined Gemini-Agena spacecraft into a higher orbit. The first attempt at such a docking mission was made for the Gemini 6 mission on October 25, 1965, but the Agena suffered an engine failure and did not reach orbit. [5] This forced postponement and replanning of the Gemini 6A mission, which performed rendezvous with Gemini 7 without docking. [6]
The GATV was first successfully launched for Gemini 8 on March 16, 1966, permitting the first successful docking in space. GATV-8 was later used as the secondary Agena target for Gemini 10, which also docked with its own GATV. GATV-9 failed to orbit when the Atlas suffered a control malfunction, forcing a similar reschedule of the Gemini 9A mission using a backup Augmented Target Docking Adapter atop an Atlas, but with no Agena rocket stage. Two more GATVs were successfully launched and used on Gemini 11 and Gemini 12.
A series of five Lunar Orbiter spacecraft were launched from August 1966 through August 1967, to help select landing sites for the Apollo lunar landing program by mapping the Moon's surface. [7] Each spacecraft weighed 850 pounds (390 kg) and was 4.9 feet (1.5 m) in diameter, minus the four extended solar panels. All launches were successful, and a total of 99 percent of the surface of the Moon (near and far side) was mapped with resolution as high as 3 ft 3 in (1 meter). Altogether the Orbiters returned 2180 high resolution and 882 medium resolution frames. The spacecraft also carried micrometeoroid sensors, which showed the average micro-meteoroid flux near the Moon to be two orders of magnitude greater than in interplanetary space, but slightly less than the near-Earth environment.
Orbiting Astronomical Observatory was a series of NASA satellites flown between 1966 and 1972 for astronomy studies. The first OAO (launched April 8, 1966) used a one-off Atlas variant, mating an Agena D to the LV-3C variant of the Atlas and encased in a Centaur-type payload shroud. The remaining three launches used actual Atlas-Centaur vehicles.
Applications Technology Satellite was a series of NASA satellites flown in 1967–69 to perform various technology tests. Only the first ATS was launched on an Atlas-Agena, the remainder using Atlas-Centaurs. ATS-1 was a partial failure when the Agena failed to restart, leaving it in LEO.
Orbiting Geophysical Observatory was a series of NASA satellites flown between 1964 and 1969 for magnetosphere studies. These satellites used several different booster types, including Thor-Agenas. Five of them used Atlas-Agenas, and OGO 5 (launched March 4, 1968) was the sole civilian use of the Atlas SLV-3A Agena.
Missile Defense Alarm System was a series of Air Force satellites flown between 1960 and 1966 for infrared detection of ballistic missile exhaust plumes on Atlas-Agena A, B, and D. There were several failures and overall program performance was poor, but it would give way to the more successful DSP satellites.
Samos was a series of Air Force satellites flown between 1960 and 1962 for photoreconnaissance on Atlas-Agena A and B. There were several failures, including an on-pad explosion of an Atlas, and the program was cancelled at the end of 1962 without ever demonstrating any operational capability.
KH-7 Gambit was a series of Air Force satellites flown between 1963 and 1966 for photoreconnaissance on Atlas-Agena D. Although there were a number of mission failures, Gambit overall was highly successful in comparison with the bungled Samos program and it returned high-value area reconnaissance of the USSR and China before giving way to KH-8 Gambit in 1967.
Rhyolite/Canyon was a series of Air Force satellites flown between 1968 and 1978 for SIGNIT intelligence on Atlas SLV-3A Agena. One Canyon mission failed when its Atlas went off course and had to be destroyed. These were the final launches of Atlas-Agena vehicles aside from the one-off Atlas F/Agena used to launch Seasat.
Vela consisted of two sets of Air Force satellites flown in 1964–65 to monitor Soviet compliance with the Nuclear Test Ban Treaty on Atlas-Agena Ds.
Snapshot was a one-off Air Force test of a nuclear satellite flown in 1965 on an Atlas-Agena D.
Mariner 1, built to conduct the first American planetary flyby of Venus, was the first spacecraft of NASA's interplanetary Mariner program. Developed by Jet Propulsion Laboratory, and originally planned to be a purpose-built probe launched summer 1962, Mariner 1's design was changed when the Centaur proved unavailable at that early date. Mariner 1, were then adapted from the lighter Ranger lunar spacecraft. Mariner 1 carried a suite of experiments to determine the temperature of Venus as well to measure magnetic fields and charged particles near the planet and in interplanetary space.
Ranger 3 was a space exploration mission conducted by NASA to study the Moon. The Ranger 3 robotic spacecraft was launched January 26, 1962 as part of the Ranger program. Due to a series of malfunctions, the spacecraft missed the Moon by 22,000 mi (35,000 km) and entered a heliocentric orbit.
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 division 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.
The Agena Target Vehicle, also known as Gemini-Agena Target Vehicle (GATV), was an uncrewed spacecraft used by NASA during its Gemini program to develop and practice orbital space rendezvous and docking techniques, and to perform large orbital changes, in preparation for the Apollo program lunar missions. The spacecraft was based on Lockheed Aircraft's Agena-D upper stage rocket, fitted with a docking target manufactured by McDonnell Aircraft. The name 'Agena' derived from the star Beta Centauri, also known as Agena. The combined spacecraft was a 26-foot (7.92 m)-long cylinder with a diameter of 5 feet (1.52 m), placed into low Earth orbit with the Atlas-Agena launch vehicle. It carried about 14,000 pounds (6,400 kg) of propellant and gas at launch, and had a gross mass at orbital insertion of about 7,200 pounds (3,300 kg).
Gemini 6A was a 1965 crewed United States spaceflight in NASA's Gemini program. The mission, flown by Wally Schirra and Thomas P. Stafford, achieved the first crewed rendezvous with another spacecraft, its sister Gemini 7. Although the Soviet Union had twice previously launched simultaneous pairs of Vostok spacecraft, these established radio contact with each other, but they had no ability to adjust their orbits in order to rendezvous and came no closer than several kilometers of each other, while the Gemini 6 and 7 spacecraft came as close as one foot (30 cm) and could have docked had they been so equipped.
Gemini 12 was a 1966 crewed spaceflight in NASA's Project Gemini. It was the 10th and final crewed Gemini flight, the 18th crewed American spaceflight, and the 26th spaceflight of all time, including X-15 flights over 100 kilometers (54 nmi). Commanded by Gemini VII veteran James A. Lovell, the flight featured three periods of extravehicular activity (EVA) by rookie Edwin "Buzz" Aldrin, lasting a total of 5 hours and 30 minutes. It also achieved the fifth rendezvous and fourth docking with an Agena target vehicle.
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 2 ft (0.61 m) to 3 ft (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.
The SAMOS or SAMOS-E program was a relatively short-lived series of reconnaissance satellites for the United States in the early 1960s, also used as a cover for the initial development of the KH-7 GAMBIT system. Reconnaissance was performed with film cameras and television surveillance from polar low Earth orbits with film canister returns and transmittals over the United States. SAMOS was first launched in 1960 from Vandenberg Air Force Base.
Mercury-Atlas 10 (MA-10) was a cancelled early crewed space mission, which would have been the last flight in NASA's Mercury program. It was planned as a three-day extended mission, to launch in late 1963; the spacecraft, Freedom 7-II, would have been flown by Alan Shepard, a veteran of the suborbital Mercury-Redstone 3 mission in 1961. However, it was cancelled after the success of the one-day Mercury-Atlas 9 mission in May 1963, to allow NASA to focus its efforts on the more advanced two-man Gemini program.
Project Gemini was the second United States human spaceflight program to fly. Conducted after the first American crewed space program, Project Mercury, while the Apollo program was still in early development, Gemini was conceived in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual astronauts flew low Earth orbit (LEO) missions during 1965 and 1966.
The Atlas-Centaur was a United States expendable launch vehicle derived from the SM-65 Atlas D missile. The vehicle featured a Centaur upper stage, the first such stage to use high-performance liquid hydrogen as fuel. Launches were conducted from Launch Complex 36 at the Cape Canaveral Air Force Station (CCAFS) in Florida. After a strenuous flight test program, Atlas-Centaur went on to launch several crucial spaceflight missions for the United States, including Surveyor 1, and Pioneer 10/11. The vehicle would be continuously developed and improved into the 1990s, with the last direct descendant being the highly successful Atlas II.
Space Launch Complex 3 (SLC-3) is a launch site at Vandenberg Space Force Base that consists of two separate launch pads. SLC-3E (East) was used by the Atlas V launch vehicle before it was decommissioned in August 2021 with the final launch taking place on November 10, 2022 at 09:49, while SLC-3W (West) has been demolished.
Atlas is a family of US missiles and space launch vehicles that originated with the SM-65 Atlas. The Atlas intercontinental ballistic missile (ICBM) program was initiated in the late 1950s under the Convair Division of General Dynamics. Atlas was a liquid propellant rocket burning RP-1 kerosene fuel with liquid oxygen in three engines configured in an unusual "stage-and-a-half" or "parallel staging" design: two outboard booster engines were jettisoned along with supporting structures during ascent, while the center sustainer engine, propellant tanks and other structural elements remained connected through propellant depletion and engine shutdown.
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.
Thorad-Agena was an American expendable launch system, derived from the Thor and Delta rockets.
The Missile Defense Alarm System, or MIDAS, was a United States Air Force Air Defense Command system of 12 early-warning satellites that provided limited notice of Soviet intercontinental ballistic missile launches between 1960 and 1966. Originally intended to serve as a complete early-warning system working in conjunction with the Ballistic Missile Early Warning System, cost and reliability concerns limited the project to a research and development role. Three of the system's 12 launches ended in failure, and the remaining nine satellites provided crude infrared early-warning coverage of the Soviet Union until the project was replaced by the Defense Support Program. MiDAS represented one element of the United States's first generation of reconnaissance satellites that also included the Corona and SAMOS series. Though MIDAS failed in its primary role as a system of infrared early-warning satellites, it pioneered the technologies needed in successor systems.
The Atlas SLV-3, or SLV-3 Atlas was an American expendable launch system derived from the SM-65 Atlas / SM-65D Atlas missile. It was a member of the Atlas family of rockets.
The Atlas LV-3B, Atlas D Mercury Launch Vehicle or Mercury-Atlas Launch Vehicle, was a human-rated expendable launch system used as part of the United States Project Mercury to send astronauts into low Earth orbit. Manufactured by Convair, it was derived from the SM-65D Atlas missile, and was a member of the Atlas family of rockets. With the Atlas having been originally designed as a weapon system, testing and design changes were made to the missile to make it a safe and reliable launch vehicle. After the changes were made and approved, the US launched the LV-3B nine times, four of which had crewed Mercury spacecraft.
Advanced Gemini was a series of proposals that would have extended the Gemini program by the addition of various missions, including crewed low Earth orbit, circumlunar and lunar landing missions. Gemini was the second crewed spaceflight program operated by NASA, and consisted of a two-seat spacecraft capable of maneuvering in orbit, docking with uncrewed spacecraft such as Agena Target Vehicles, and allowing the crew to perform tethered extra-vehicular activities.
The ascent propulsion system (APS) or lunar module ascent engine (LMAE) is a fixed-thrust hypergolic rocket engine developed by Bell Aerosystems for use in the Apollo Lunar Module ascent stage. It used Aerozine 50 fuel, and N
2O
4 oxidizer. Rocketdyne provided the injector system, at the request of NASA, when Bell could not solve combustion instability problems.