The Centaur is a family of rocket propelled upper stages that has been in use since 1962. It is currently produced by U.S. launch service provider United Launch Alliance,with one main active version and one version under development. The 3.05 m (10.0 ft) diameter Common Centaur/Centaur III flies as the upper stage of the Atlas V launch vehicle,and the 5.4 m (18 ft) diameter Centaur V has been developed as the upper stage of ULA's new Vulcan rocket. Centaur was the first rocket stage to use liquid hydrogen (LH2) and liquid oxygen (LOX) propellants,a high-energy combination that is ideal for upper stages but has significant handling difficulties.
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 1989. There were two main variants,the Delta 6000 and Delta 7000,with the latter also having "Light" and "Heavy" subvariants. During its career,Delta II flew several notable payloads,including 24 Global Positioning System (GPS) Block II satellites,several dozen NASA payloads,and 60 Iridium communication satellites. The rocket flew its final mission,ICESat-2,on 15 September 2018,earning the launch vehicle a streak of 100 successful missions in a row,with the last failure being GPS IIR-1 in 1997. In the late 1990s,Delta II was developed further into the unsuccessful Delta III,which was in turn developed into the more capable and successful Delta IV,though the latter shares little heritage with the original Thor and Delta rockets.
The Delta rocket family was a versatile range of American rocket-powered expendable launch systems that provided space launch capability in the United States from 1960 to 2024. Japan also launched license-built derivatives from 1975 to 1992. More than 300 Delta rockets were launched with a 95% success rate. The series was phased out in favor of the Vulcan Centaur,with the Delta IV Heavy rocket's last launch occurring on April 9,2024.
Delta IV was a group of five expendable launch systems in the Delta rocket family. It flew 45 missions from 2002 to 2024. Originally designed by Boeing's Defense,Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program,the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was primarily a launch vehicle for United States Air Force (USAF) military payloads,but was also used to launch a number of United States government non-military payloads and a single commercial satellite.
The Saturn I was a rocket designed as the United States' first medium lift launch vehicle for up to 20,000-pound (9,100 kg) low Earth orbit payloads. Its development was taken over from the Advanced Research Projects Agency (ARPA) in 1958 by the newly formed civilian NASA. Its design proved sound and flexible. It was successful in initiating the development of liquid hydrogen-fueled rocket propulsion,launching the Pegasus satellites,and flight verification of the Apollo command and service module launch phase aerodynamics. Ten Saturn I rockets were flown before it was replaced by the heavy lift derivative Saturn IB,which used a larger,higher total impulse second stage and an improved guidance and control system. It also led the way to development of the super-heavy lift Saturn V which carried the first men to landings on the Moon in the Apollo program.
The Space Shuttle external tank (ET) was the component of the Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplied the fuel and oxidizer under pressure to the three RS-25 main engines in the orbiter. The ET was jettisoned just over 10 seconds after main engine cut-off (MECO) and it re-entered the Earth's atmosphere. Unlike the Solid Rocket Boosters,external tanks were not re-used. They broke up before impact in the Indian Ocean,away from shipping lanes and were not recovered.
National Security Space Launch (NSSL) is a program of the United States Space Force (USSF) intended to assure access to space for United States Department of Defense and other United States government payloads. The program is managed by the Assured Access to Space Directorate (SSC/AA) of the Space Force's Space Systems Command (SSC),in partnership with the National Reconnaissance Office.
The RL10 is a liquid-fuel cryogenic rocket engine built in the United States by Aerojet Rocketdyne that burns cryogenic liquid hydrogen and liquid oxygen propellants. Modern versions produce up to 110 kN (24,729 lbf) of thrust per engine in vacuum. Three RL10 versions are in production for the Centaur upper stage of the Atlas V and the DCSS of the Delta IV. Three more versions are in development for the Exploration Upper Stage of the Space Launch System and the Centaur V of the Vulcan rocket.
Atlas II was a member of the Atlas family of launch vehicles,which evolved from the successful Atlas missile program of the 1950s. The Atlas II was a direct evolution of the Atlas I,featuring longer first-stage tanks,higher-performing engines,and the option for strap-on solid rocket boosters. It was designed to launch payloads into low Earth orbit,geosynchronous transfer orbit or geosynchronous orbit. Sixty-three launches of the Atlas II,IIA and IIAS models were carried out between 1991 and 2004;all sixty-three launches were successes,making the Atlas II a highly reliable space launch system. The Atlas line was continued by the Atlas III,used between 2000 and 2005,and the Atlas V,which is still in use as of 2024.
Aerojet Rocketdyne is a subsidiary of American defense company L3Harris that manufactures rocket,hypersonic,and electric propulsive systems for space,defense,civil and commercial applications. Aerojet traces its origins to the General Tire and Rubber Company established in 1915,while Rocketdyne was created as a division of North American Aviation in 1955. Aerojet Rocketdyne was formed in 2013 when Aerojet and Pratt &Whitney Rocketdyne were merged,following the latter's acquisition by GenCorp from Pratt &Whitney. Aerojet Rocketdyne was acquired by L3Harris in July 2023 for $4.7 billion.
Delta III was an expendable launch vehicle made by McDonnell Douglas. Development was canceled before the vehicle became operational. The vehicle is the third generation of the Delta rocket family,developed from the highly successful Delta II to help meet the launch demand of larger satellites. While the Delta III never had a successful launch,some of the technologies developed were used in its successor,the Delta IV.
The RS-68 (Rocket System-68) was a liquid-fuel rocket engine that used liquid hydrogen (LH2) and liquid oxygen (LOX) as propellants in a gas-generator cycle. It was the largest hydrogen-fueled rocket engine ever flown.
United Launch Alliance,LLC (ULA) is an American launch service provider formed in December 2006 as a joint venture between Lockheed Martin Space and Boeing Defense,Space &Security. The company designs,assembles,sells and launches rockets,but the company subcontracts out the production of rocket engines and solid rocket boosters.
In rocketry,an adapter is a hollow cylindrical or conical segment which provides a sound aerodynamic and structural connection,either between rocket stages or between a spacecraft and the top rocket stage. It may shroud and protect vulnerable systems such as electrics or machinery of rocket engines/spacecraft from weather or noise caused by running engines. It is discarded during staging.
The Advanced Cryogenic Evolved Stage (ACES) was a proposed liquid oxygen/liquid hydrogen upper-stage for use on a number of different launch vehicles produced by Boeing,Lockheed Martin,United Launch Alliance (ULA). During the last five years of the program,ACES was proposed for eventual use on the Vulcan space launch vehicle designed by the U.S. company United Launch Alliance. The ACES concept had the objective to improve the on-orbit lifespan of current upper stages.
The Space Launch System (SLS) is an American super heavy-lift expendable launch vehicle used by NASA. As the primary launch vehicle of the Artemis Moon landing program,SLS is designed to launch the crewed Orion spacecraft on a trans-lunar trajectory. The first SLS launch was the uncrewed Artemis I,which took place on 16 November 2022.
Pratt &Whitney Rocketdyne (PWR) was an American company that designed and produced rocket engines that use liquid propellants. It was a division of Pratt &Whitney,a fully owned subsidiary of United Technologies Corporation. It was headquartered in Canoga Park,Los Angeles,California. In 2013,the company was sold to GenCorp,becoming part of Aerojet Rocketdyne.
The Exploration Upper Stage (EUS) is a rocket stage under development that will be used for future flights of NASA's Space Launch System (SLS). Used on SLS Block 1B and Block 2,it will replace the SLS Block 1's Interim Cryogenic Propulsion Stage. The stage will be powered by four RL10C-3 engines burning liquid oxygen and liquid hydrogen to produce a total thrust of 433.1 kN (97,360 lbf). The EUS is expected to first fly on Artemis IV in 2028.
The MARC-60,also known as MB-60,MB-XX,and RS-73,is a liquid-fuel cryogenic rocket engine designed as a collaborative effort by Japan's Mitsubishi Heavy Industries and US' Aerojet Rocketdyne. The engine burns cryogenic liquid oxygen and liquid hydrogen in an open expander cycle,driving the turbopumps with waste heat from the main combustion process.
