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RS-25

The RS-25, also known as the Space Shuttle Main Engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is used on the Space Launch System.

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Associated LV
Space Shuttle · Space Launch System
Chamber pressure
2,994 psi (20.64 MPa)
Country of origin
United States
Cycle
Fuel-rich dual-shaft staged combustion
Designer
Rocketdyne
Diameter
2.4 m (96 in)

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Map overview Semantic statistics

RS-25

Nodes147
Edges146
Triples177
Avg. degree1.99
Density0.013605
Components1

How this topic connects Entity context

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RS-25

Top relations

related to Space Launch System · 32
RS-25 → Artemis, Artemis II, Block II RS-25D, E2045, E2047, E2056, E2058, E2059, E2060, E2061, E2062, E2063, Endeavour, For Artemis, For Artemis II, In, Main Propulsion Systems, MPS, NASA, November
related to External links · 24
RS-25 → Alabama, American Engineering Record, HAER, Harris County, Houston, Huntsville Archives, Johnson Space Center, Lawrence, Lyndon, NASA Parkway, No, RS-25D, Space Shuttle Main Engine, Space Transportation System, Special Collections Files, Spherical, SSME, SSME Processing Facility, Stennis Space CenterLawrence, The University
related to Development · 21
RS-25 → Apollo, As, At, Center, F-1, HG-3, It, J-2, Laval, Meanwhile, NASA's Marshall Space Flight, Pratt, Project Isinglass, Rocketdyne, S-II, S-IVB, Saturn, The, US Air Force, Whitney
related to Space Shuttle program · 20
RS-25 → After, At, Boosters, Each Space Shuttle, ET, If, MECO, MPS, Orbiter Processing Facility, Processing Facility, RPL, Space Shuttle, Space Shuttle Main Engine, Space Shuttle Solid Rocket, SRBs, SSMEPF, Stennis Space Center, The, US, Vehicle Assembly Building
related to Components · 17
RS-25 → From, Fuel, HPFTP, HPOTP, HPTPs, In, LPFTP, LPOTP, MCC, MPS, Once, SLS, Space Launch System, Space Shuttle, Space Shuttle's, The, The RS-25
related to XS-1 · 13
RS-25 → Aerojet Rocketdyne, Aerojet Rocketdyne AR-22, AR-22, Boeing, DARPA, In July, NASA, On January, On May, The, The AR-22, The Boeing Company, XS-1
related to Constellation program · 12
RS-25 → Ares, Constellation, During, Each, It, NASA, RS-25D, Space Shuttle, The, This, US, While
related to Nozzle · 10
RS-25 → At, However, Laval, On, Rocketdyne, Space Shuttle, The, The RS-25, Thermal, This
Manufacturer · 3
RS-25 → Aerojet Rocketdyne (2013–present), Pratt & Whitney Rocketdyne (2005–2013), Rocketdyne (1972–2005)
Associated LV · 2
RS-25 → Space Launch System, Space Shuttle

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Important terminology

engine engines space main fuel system oxidizer shuttle nozzle thrust launch chamber used power first combustion use liquid seconds rocketdyne

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
RS-25Associated LVSpace Shuttle1.00infobox
RS-25Associated LVSpace Launch System1.00infobox
RS-25Chamber pressure2,994 psi (20.64 MPa)1.00infobox
RS-25Country of originUnited States1.00infobox
RS-25CycleFuel-rich dual-shaft staged combustion1.00infobox
RS-25DesignerRocketdyne1.00infobox
RS-25Diameter2.4 m (96 in)1.00infobox
RS-25Dry mass3,177 kg (7,004 lb)1.00infobox
RS-25First flightApril 12, 1981 (1981-04-12) (STS-1)1.00infobox
RS-25Length4.3 m (168 in)1.00infobox
RS-25ManufacturerRocketdyne (1972–2005)1.00infobox
RS-25ManufacturerPratt & Whitney Rocketdyne (2005–2013)1.00infobox
RS-25ManufacturerAerojet Rocketdyne (2013–present)1.00infobox
RS-25Mass flow514.49 kg/s (1,134.26 lb/s)1.00infobox
RS-25Mixture ratio6.03:11.00infobox
RS-25NotesData is for RS-25D at 109% of rated power level.1.00infobox
RS-25Nozzle ratio78:11.00infobox
RS-25PredecessorHG-31.00infobox
RS-25PropellantLOX / .mw-parser-output .template-chem2-su{display:inline-block;font-size:80%;line-height:1;vertical-align:-0.35em}.mw-parser-output .template-chem2-su>span{display:block;text-a…1.00infobox
RS-25Specific impulse, sea-level366 s (3.59 km/s)1.00infobox
RS-25Specific impulse, vacuum452.3 s (4.436 km/s)1.00infobox
RS-25StatusIn use1.00infobox
RS-25Throttle range67–109%1.00infobox
RS-25Thrust, sea-level1,860 kN (418,000 lbf)1.00infobox
RS-25Thrust, vacuum2,279 kN (512,300 lbf)1.00infobox
RS-25Thrust-to-weight ratio73.11.00infobox

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