# List of space programs of the United States

The United States has developed many space programs since the beginning of the spaceflight era in the mid-20th century. The government runs space programs by three primary agencies: NASA for civil space; the United States Space Force for military space; and the National Reconnaissance Office for intelligence space. These entities have invested significant resources to advance technological approaches to meet objectives. In the late 1980s, commercial interests emerged in the space industry and have expanded dramatically, especially within the last 10 to 15 years.
NASA delivers the most visible elements of the U.S. space program. From crewed space exploration and the Apollo 11 landing on the Moon, to the Space Shuttle, International Space Station, Voyager, the Mars rovers, numerous space telescopes, and the Artemis program, NASA delivers on the civil space exploration mandate. NASA also cooperates with other U.S. civil agencies such as the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS) to deliver space assets supporting the weather and civil remote sensing mandates of those organizations. In 2022, NASA's annual budget was approximately $24 billion.
The Department of Defense delivers the military space programs. In 2019, the U.S. Space Force started as the primary DoD agent for delivery of military space capability. Systems such as the Global Positioning System, which is ubiquitous to users worldwide, was developed and is maintained by the DoD. Missile warning, defense weather, military satellite communications, and space domain awareness also acquire significant annual investment. In 2023, the annual DoD budget request focused on space is $24.5 billion dollars.
The Intelligence Community, through entities that include the National Reconnaissance Office (NRO), invests significant resources in space. Surveillance and reconnaissance are the primary focuses of these entities.
Commercial space activity in the United States was facilitated by the passage of the Commercial Space Launch Act in October 1984. Commercial crewed program activity was spurred by the establishment of the $10 million Ansari X Prize in May 1996.

## Definition of space flight

Space programs of the United States date to the start of the Space Age in the late 1940s and early 1950s. Programs involve both crewed systems and uncrewed satellites, probes and platforms to meet diverse program objectives.
From a definition perspective, the criteria for what constitutes spaceflight vary. In the United States, professional, military, and commercial astronauts who travel above an altitude of 50 miles (80 km) are awarded astronaut wings. The Fédération Aéronautique Internationale defines spaceflight as any flight over 62 miles (100 km). This article follows the US definition of spaceflight. Similarly, for uncrewed missions, systems are required to travel above the same altitude thresholds.

## Government-led programs

The following summarizes the major space programs where the United States government plays a leadership role in managing program delivery.

### Crewed government-led programs

| Program | Purpose | Timeline | Organization(s) | Flights | Exemplar mission(s) |
| X-15 program | R&D | 1957–1968 | US Air Force (1957–1968)NASA (1958–1968) | 13 | X-15 Flight 91 |
| Project Mercury | R&D | 1958–1963 | NASA | 11 | Mercury-Atlas 6 |
| Project Gemini | Exploration | 1961–1966 | NASA | 19 | Gemini 4 |
| Project Apollo | Exploration | 1961–1972 | NASA | 14 | Apollo 11 |
| Manned Orbiting Laboratory | Space Operations | 1962–1969 | US Air Force | 1 | Test Flight |
| Space Shuttle program | Space Transportation | 1972–2011 | NASA | 134 | 5–HST (STS-61)11–Mir (STS-71, STS-89)37–ISS (STS-88)81–Science (STS-1) |
| Skylab program | Space Operations | 1973–1974 | NASA | 4 | Skylab 2 |
| Spacelab program | Space Operations | 1973–1998 | ESANASA | 16 | STS-50 |
| Apollo–Soyuz Test Project | Space Operations | 1975 | NASASoviet Union | 1 | APAS-75 Docking System |
| International Space Station program | Space Operations | 1984–present | NASACSA (Canada)ESA (Europe)JAXA (Japan)Roscosmos (Russia) | 26 years, 102 days in orbit | STS-104STS-134Soyuz TMA-11Soyuz TMA-08M |
| Constellation program | Exploration | 2000s–2010 | NASA | 1 | Ares I-X |
| Journey to Mars program | Exploration | 2010–2017 | NASA | 1 | Exploration Flight Test-1 |
| Lunar Gateway program | Exploration | 2017–present | NASACSA (Canada)ESA (Europe)JAXA (Japan) | 0 | Habitation and Logistics OutpostInternational Habitation Module |
| Artemis Program | Exploration | 2017–present | NASACSA (Canada)ESA (Europe)JAXA (Japan) | 1 | Orion MPCVSpace Launch SystemStarship HLS |

### Uncrewed government-led programs

| Program | Purpose | Timeline | Organization(s) | Flights | Exemplar mission(s) |
| Viking sounding rocket | R&D | 1949–1957 | Naval Research Laboratory | 11 | Viking 11 (1954) |
| Project Vanguard | R&D | 1956–1959 | Naval Research Laboratory | 3 | Vanguard 1 |
| Project Farside | R&D | 1957 | AFOSR | 6 | |
| Explorers Program | Exploration | 1958–present | US Army (1958)NASA (1958–present) | 91 | HETE 2WISE |
| Pioneer program | Exploration | 1958–1992 | NASAUS Air Force (1958–1960)US Army (1958–1960) | 8 | Pioneer 11Pioneer Venus Orbiter |
| KH-1 to KH-6 Corona | Reconnaissance | 1959–1972 | Central Intelligence AgencyUS Air Force | 142 | Discoverer 1 |
| Samos | Reconnaissance | 1960–1962 | US Air Force | 7 | Samos 6 |
| Television Infrared Observation Satellite | Weather | 1960–1968 | NASAARPA | 10 | TIROS-8 |
| Transit | Navigation | 1960–1988 | Naval Research LaboratoryApplied Physics Laboratory | 36 | Transit 3B |
| Ranger program | Exploration | 1961–1965 | NASA | 4 | Ranger 7 |
| Strategic missile warning programs | Surveillance | 1960–present | US Space Force | 39 | MIDASDSPSBIRS |
| Orbiting Solar Observatory | Heliophysics | 1962–1975 | NASA | 8 | OSO 3 |
| Mariner program | Exploration | 1962–1973 | NASA | 7 | Mariner 6 and 7 |
| Centaur upper stage program | Space Transportation | 1962–2003 | US Army (1957–1960)NASA (1960–1989)US Air Force (1987–2003) | 91 | 68–Atlas7–Titan IIIE0–STS16–Titan IV |
| Environmental Research Satellite | Technology | 1962–1971 | US Air Force | 33 | ERS 5 |
| Defense Meteorological Satellite Program (DMSP) | Weather | 1962–present | US Air ForceNOAA | 39 | |
| Lunar Orbiter program | Exploration | 1963–1967 | NASA | 5 | Lunar Orbiter 3 |
| KH-7 Gambit | Reconnaissance | 1963–1967 | NROUS Air Force | 38 | |
| Project Vela | Nuclear test detection | 1963–1970 | US Air ForceARPA | 12 | Vela 1AVela 1B |
| Nimbus program | Weather | 1964–1978 | NASA | 6 | Nimbus 1 |
| National Geodetic Satellite Program | Geodesy | 1964–1971 | NASA | 6 | BE-CPAGEOSGEOS-2ANNA 1B |
| Electronic & Geodetic Ranging Satellite (EGRS) | Navigation | 1964–1970 | US ArmyNaval Research Laboratory | 5 | EGRS 1 |
| Space Experiment Support Program | R&D | 1965–1971 | Naval Research LaboratoryAir Force Research Laboratory | 6 | SOLRAD |
| Orbiting Vehicle | Technology | 1965–1971 | US Air Force | 37 | OV1-9 |
| Lincoln Experimental Satellite | Communications | 1965–1976 | US Air ForceMIT Lincoln Laboratory | 8 | LES-1LES-3 |
| Orbiting Astronomical Observatory (OAO) | Astronomy | 1966–1972 | NASAUK Science Research Council | 2 | Orbiting Astronomical Observatory 3 |
| KH-8 Gambit 3 | Reconnaissance | 1966–1984 | NROUS Air Force | 54 | |
| Applications Technology Satellites | CommunicationsNavigationWeather | 1966–1979 | NASA | 6 | ATS-3 |
| Defense Satellite Communications System | Communications | 1966–present | US Air Force | 63 | DSCS-III |
| KH-9 Hexagon | Reconnaissance | 1971–1984 | NROUS Air Force | 19 | |
| Space Test Program | R&D | 1971–present | Naval Research LaboratoryAir Force Research LaboratoryUS Space Force | 251 | C/NOFS |
| Landsat program | Earth Science | 1972–present | NASAUSGS | 9 | Landsat 9 |
| Earth and Ocean Dynamics Applications Program | Geodesy | 1972–1978 | NASA | 6 | LAGEOSSeasatMagsatGEOS-3 |
| NAVSTAR GPS | Navigation | 1973–present | US Air Force (1973–2019) US Space Force (2019 onward) | 77 | GPS Block III |
| Geostationary Operational Environmental Satellite (GOES) | Weather | 1975–present | NOAANASA | 18 | GOES 8GOES 13 |
| Strategic planetary missions | Exploration | 1975–present | NASA | 8 | Voyager 2Cassini–Huygens |
| HEAO Program | Astrophysics | 1977–1979 | NASA | 3 | Einstein Observatory |
| Polar Operational Environmental Satellites (POES) | Weather | 1978–present | NOAAEumetsatNASA | 16 | NOAA-9NOAA-20 |
| Tracking and Data Relay Satellite System (TDRSS) | Communications | 1983–present | NASA | 14 | TDRS-1TDRS-10 |
| Milstar | Communications | 1985–present | US Air Force | 6 | |
| UHF Follow-On program | Communications | 1988–present | US Navy | 11 | |
| Medium Launch Vehicle II (MLV-II) | Space Transportation | 1988–2004 | US Air Force | 14 | Atlas IIAtlas IIAS |
| Discovery program | Exploration | 1990–present | NASA | 12 | StardustMESSENGER |
| Great Observatories program | Astrophysics | 1990–present | NASA | 4 | HSTCGROChandra X-ray Observatory |
| Mars Exploration Program | Exploration | 1993–present | NASA | 8 | Mars Global SurveyorOpportunity Rover |
| Global Geospace Science | Astrophysics | 1994–1996 | NASA | 2 | WindPolar |
| Evolved Expendable Launch Vehicle | Space Transportation | 1998–present | US Air Force | 106 | xx–Atlas V36–Delta IVxx–Falcon 9 |
| New Millennium Program | Exploration | 1996–2017 | NASA | 5 | EO-1Deep Space 1 |
| Earth System Science Pathfinder (ESSP) | Earth Science | 1996–present | NASA | 7 | GRACECALIPSOCYGNSS |
| Earth Observing System | Earth Science | 1999–present | NASA | 5 | TerraAquaAura |
| Solar Terrestrial Probes program | Astrophysics | 2001–2003 | NASA | 4 | TIMEDSTEREOMagnetospheric Multiscale Mission |
| New Frontiers program | Exploration | 2003–present | NASA | 3 | New HorizonsOSIRIS-REx |
| Tactical Satellite Program | Technology | 2003–2013 | Air Force Research LaboratoryNaval Research Laboratory | 3 | TacSat-2 |
| University Nanosatellite Program | Technology | 2004–present | Air Force Research Laboratory | 20 | Cornell University Satellite |
| X-37B program | R&D | 2006–present | US Air Force (2006–2019)US Space Force (2019–present) | 6 | OTV-3 |
| Lunar Precursor Robotic Program | Astrophysics | 2006–2013 | NASA | 3 | LROLCROSSLADEE |
| AEHF Satellite Program | Communications | 2010–present | US Space Force | 6 | AEHF-1 |
| Living With a Star | Heliophysics | 2010–present | NASA | 4 | Solar Dynamics ObservatoryParker Solar ProbeVan Allen Probes |
| Wideband Global Satcom Program | Communications | 2011–present | US Space Force | 10 | WGS-4 |
| Earth Systematic Missions (ESM) Program | Earth Science | 2017–present | NASA | 10 | GRACE-FOSWOTPACE |
| Origins Program | Astrophysics | 2021–present | NASA | 3 | JWST |
| Weather System Follow-on Program | Space weather | 2024–present | US Space Force | 1 | WSF-M1 |

## Commercial space programs

The following summarizes the major space programs where private interests play the leadership role in managing program delivery.

### Crewed commercial programs

| Program | Purpose | Timeline | Organization(s) | Flights | Exemplar mission(s) |
| Space Adventures | Space tourism | 1998–present | NASARoscosmosSpace Adventures | 7 | Soyuz TM-32Soyuz MS-20 |
| SpaceShipOne | Space tourism | 2003–2004 | Scaled Composites | 3 | SpaceShipOne flight 16P |
| SpaceShipTwo | Space tourism | 2010–present | Virgin Galactic | 10 | Virgin Galactic Unity 22 Galactic 02 |
| Blue Origin New Shepard | Space tourism | 2015–present | Blue Origin | 24 | Blue Origin NS-18 |
| DearMoon lunar tourism | Space tourism | 2018–present | Yusaku MaezawaSpaceX | 0 | |
| Axiom Space | Space tourism | 2020–present | Axiom SpaceSpaceX | 3 | Axiom Mission 1 Axiom Mission 2 |
| Polaris program | Space tourism | 2021–present | Jared IsaacmanSpaceX | 1 | Inspiration4 |
| Commercial Crew Program | Space transportation | 2011–present | NASABoeingSpaceX | 7 | SpaceX Crew-1SpaceX Crew-3 |
| SpaceX Starship | Space Transportation | 2012–present | SpaceX | 0 | |
| Orbital Reef Space Station | Space Operations | 2021–present | Blue Origin | 0 | |

### Uncrewed commercial programs

| Program | Purpose | Timeline | Organization(s) | Flights | Exemplar mission(s) |
| Telstar | Satellite communications | 1962–1995 | AT&T | 8 | Telstar 301 |
| Comstar | Satellite communications | 1963–2000 | Comsat General Corporation | 4 | Comstar D-4 |
| Westar | Satellite communications | 1975–1988 | Western Union | 7 | Westar 1 |
| Satcom | Satellite communications | 1975–2001 | RCA Americom | 13 | GE-1 |
| SBS | Satellite communications | 1975–1991 | Satellite Business Systems | 6 | SBS 2 |
| Galaxy | Satellite communications | 1983–1997 | Hughes Communications | 9 | Galaxy 1 |
| Commercial Launch Services (Atlas) | Space Transportation | 1987–19952006–present | General Dynamics (1987–1994)Martin Marietta (1994–1995) | 9 (1990–93)11 (1994–95) | AC-69/Atlas I |
| Iridium | Satellite communications | 1987–present | Iridium Communications | 170 | Iridium 77 |
| Globalstar | Satellite communications | 1991–present | Globalstar | 84 | |
| Digital Globe | Earth Imaging | 1992–present | Maxar Technologies | 8 | WorldView-1 |
| Orbcomm | Satellite data messaging | 1992–present | Orbcomm | 62 | |
| International Launch Services (Atlas, Proton) | Space transportation | 1995–2006 | Lockheed Martin (USA)Khrunichev (Russia)Energia (Russia) | 100 | |
| Sea Launch (Zenit) | Space transportation | 1995–2014 | Boeing (USA)Energia (Russia)Aker Solutions (Norway)KB Pivdenne (Ukraine) | 36 | |
| DirecTV | Satellite Television | 1995–present | DirecTV | 19 | DirecTV T10 satellite |
| Dish Network | Satellite Television | 1996–present | DISH Network Corporation | 16 | EchoStar X |
| Sirius XM Radio | Satellite Radio | 1997–present | Sirius Satellite Radio (1998–2008)XM Radio (1999–2008)Sirius XM Radio (2008–present) | 13 | Sirius FM-5 |
| SpaceX Launch Services | Space transportation | 2002–present | SpaceX | xx | |
| Commercial Orbital Transportation Services | Space transportation | 2006–2013 | Orbital SciencesNASASpaceX | 3 | Antares A-ONESpaceX COTS Flight 1 |
| United Launch Alliance Commercial Launch Services | Space Transportation | 2006–present | BoeingLockheed Martin | xx | |
| Commercial Resupply Services | Space transportation | 2008–2020 (Phase 1)2016–present (Phase 2) | NASAOrbital Sciences (2008–2015)Orbital ATK (2015–2018)NG (2018–present)SpaceXSierra Nevada (2016–present) | 29 (Phase 1)9 (Phase 2) | SpaceX CRS-1Cygnus Orb-2 |
| Planetscope satellite constellation | Earth imaging | 2010–present | Planet Labs | 487 | List of Flock satellite types |
| Rocket Lab (Electron) | Space Transportation | 2013–present | Rocket Lab | 41 | List of Electron launches |
| Starlink | Satellite Internet Service | 2016–present | SpaceX | 5,330 | |
| Commercial Lunar Payload Services | Space transportation | 2018–present | NASAAstrobotic TechnologyIntuitive MachinesMasten Space Systems | 3 | Astrobotic Peregrine Lander |