{
  "id": "lockheed-gps-iii",
  "title": "GPS III satellite",
  "maker": "Lockheed Martin (navigation payload by ITT)",
  "maker_type": "Commercial",
  "kind": "satellite",
  "category": "platforms",
  "page": "https://spacemushroom.com/space-products/lockheed-gps-iii/",
  "website": "https://www.lockheedmartin.com/en-us/products/gps.html",
  "summary": "US Space Force navigation satellite built on the Lockheed Martin A2100 bus; the public sources found name few structural materials.",
  "application": "Navigation satellite for the GPS constellation, giving positioning and timing signals to military and civil users. GPS III adds a civil signal, better accuracy and anti-jamming, with a 15-year design life.",
  "story": {
    "headline": "GPS III is a Lockheed Martin satellite that sends positioning and timing signals to civil and military users.",
    "intro": [
      "GPS III is a navigation satellite for the US Space Force. Its signals give military and civil users their position and the time, and this generation adds a civil signal, better accuracy and more resistance to jamming. Lockheed Martin built the satellite body, or bus, on its A2100 design, and ITT built the navigation payload.",
      "Each satellite hosts three enhanced rubidium atomic clocks, with a fourth slot kept for an experimental clock design such as a hydrogen maser. The tanks that hold the fuel and the pressurising gas are made of lightweight, high-strength composite. One antenna has eight deployable elements of the jack-in-the-box type."
    ],
    "built": [
      {
        "title": "Navigation payload",
        "text": "The payload computer, called the mission data unit, includes the waveform generator first used on the GPS IIR-M satellites. L-band transmitters send the L1, L2, L3 and L5 signals. Three enhanced rubidium atomic clocks keep time, and a fourth slot is kept free for an experimental clock.",
        "parts": [
          "Atomic frequency standards (3)",
          "Navigation payload element (NPE)",
          "Mission data unit (MDU) payload computer",
          "L-band transmitters (L1, L2, L3, L5)",
          "Fourth clock slot (experimental frequency standard)"
        ]
      },
      {
        "title": "Engine, thrusters and tanks",
        "text": "A liquid apogee engine handles the final move into orbit. Thrusters of 5 lbf, or pounds of force, make the large manoeuvres, and the smaller 0.2 lbf thrusters handle coarse ones such as periodic station keeping. Orbital ATK made the propellant and pressurant tanks from lightweight, high-strength composite.",
        "parts": [
          "Liquid apogee engine (LAE)",
          "5-lbf thrusters",
          "0.2-lbf thrusters",
          "Propellant and pressurant tanks"
        ]
      },
      {
        "title": "Power and pointing",
        "text": "Power comes from solar arrays, batteries and a power regulation unit. To control its orientation the satellite has coarse sun sensors, earth sensors and an inertial measurement unit, with reaction wheels and magnetic torque rods for fine manoeuvres.",
        "parts": [
          "Solar arrays",
          "Power regulation unit",
          "Coarse sun sensors, earth sensors and inertial measurement unit",
          "Reaction wheels",
          "Magnetic torque rods"
        ]
      },
      {
        "title": "Antennas and links",
        "text": "The antenna subsystem has an Earth-coverage L-band panel, S-band antennas and UHF antennas. A further antenna has eight deployable elements of the jack-in-the-box type, designed and made by Northrop Grumman Astro Aerospace. General Dynamics was subcontractor for the communications payload.",
        "parts": [
          "Earth coverage L-band antenna panel",
          "S-band antennas",
          "UHF antennas",
          "Deployable antenna with 8 JIB elements",
          "Enhanced crosslink transponder subsystem (ECTS)"
        ]
      }
    ],
    "materials": [
      {
        "name": "Rubidium",
        "mid": "rubidium",
        "where": "In the three enhanced atomic clocks on each satellite. SV10 also carried a demonstration digital rubidium clock."
      },
      {
        "name": "Lightweight, high-strength composite",
        "mid": "fibre-reinforced-polymer-composite",
        "where": "The propellant and pressurant tanks, made by Orbital ATK. The type of composite is not named."
      },
      {
        "name": "Nickel-hydrogen cells",
        "mid": "nickel-hydrogen-cell",
        "where": "The 2011 design names these for the batteries, though lithium-ion was also mentioned as lighter. The flown chemistry is not confirmed."
      }
    ],
    "connections": "Most GPS III satellites flew on SpaceX Falcon 9 rockets, whose first stage burns nine Merlin engines. SV02 flew on a United Launch Alliance Delta IV in August 2019. Lockheed Martin built them on its A2100 bus, borrowing design elements from the earlier GPS Block IIR and IIR-M satellites. ITT, later L3Harris, built the navigation payload. SV10, launched on 21 April 2026, paves the way for the GPS IIIF series.",
    "unknown": "Little is said about what the structure, panels, solar cells and thermal blankets are made of. Published figures for the satellite's mass do not agree, and the flight battery chemistry is unconfirmed. The description of the bus dates from the design stage, so the flown hardware may differ.",
    "facts": [
      {
        "label": "Design life",
        "value": "15 years (12-year mean mission duration)"
      },
      {
        "label": "Bus",
        "value": "Lockheed Martin A2100"
      },
      {
        "label": "Atomic clocks",
        "value": "Three enhanced rubidium clocks per satellite"
      },
      {
        "label": "Operational orbit",
        "value": "about 12,550 miles above Earth"
      },
      {
        "label": "Last satellite launched",
        "value": "SV10 launched 21 April 2026"
      }
    ]
  },
  "specifications": [
    {
      "label": "Design life",
      "value": "15 years (12-year mean mission duration)",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "a 12-year mean mission duration and a 15-year design life"
    },
    {
      "label": "Bus",
      "value": "Lockheed Martin A2100",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "based on the award-winning Lockheed Martin A2100 bus design"
    },
    {
      "label": "SV01 mass",
      "value": "About 4,400 kg (9,700 lb); secondary source",
      "source_url": "https://en.wikipedia.org/wiki/USA-289",
      "quote": "weighs in at 4,400kg (9,700lbs)"
    },
    {
      "label": "Atomic clocks",
      "value": "Three enhanced rubidium clocks per satellite",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "Each GPS III SV hosts three enhanced rubidium AFSs"
    },
    {
      "label": "Final block launch",
      "value": "SV10 launched 21 April 2026",
      "source_url": "https://www.lockheedmartin.com/en-us/products/gps.html",
      "quote": "On April 21, 2026, Lockheed Martin-built GPS III SV10"
    },
    {
      "label": "Launch mass (Wikipedia)",
      "value": "3,880 kg (8,550 lb)",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
      "quote": "Launch mass 3,880 kg (8,550 lb)"
    },
    {
      "label": "Dry mass (Wikipedia)",
      "value": "2,269 kg (5,002 lb)",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
      "quote": "Dry mass 2,269 kg (5,002 lb)"
    },
    {
      "label": "End-of-life power (Wikipedia)",
      "value": "4,480 W",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
      "quote": "Power 4480 watts (end of life)"
    },
    {
      "label": "Operational orbit",
      "value": "about 12,550 miles above Earth",
      "source_url": "https://news.lockheedmartin.com/2020-06-30-Third-Lockheed-Martin-Built-GPS-III-Satellite-Now-Climbing-To-Orbit-On-Its-Own-Power",
      "quote": "climb to its operational orbit, approximately 12,550 miles above the Earth"
    },
    {
      "label": "Accuracy and anti-jamming",
      "value": "3x better accuracy and up to 8x improved anti-jamming",
      "source_url": "https://www.lockheedmartin.com/en-us/products/gps.html",
      "quote": "3x better accuracy"
    },
    {
      "label": "Navigation accuracy requirement",
      "value": "1.0 m user range error at 24 hours",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "GPS III will be required to meet a 1.0-meter URE requirement at 24 hours"
    },
    {
      "label": "M-code received power",
      "value": "at least -153 dBW at five degrees elevation",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "The GPS III M-code received signal power at Earth will be at least -153 dBW at five degrees elevation"
    },
    {
      "label": "Production facility",
      "value": "GPS III Processing Facility near Denver, $128 million",
      "source_url": "https://news.lockheedmartin.com/2018-12-23-You-Are-Here-First-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands",
      "quote": "$128-million GPS III Processing Facility near Denver"
    },
    {
      "label": "Final launch",
      "value": "SV10, 21 April 2026, 2:53 a.m. ET",
      "source_url": "https://news.lockheedmartin.com/2026-04-21-Lockheed-Martin-Launches-GPS-III-Satellite,-Paving-the-Way-for-Next-Generation-GPS-IIIF-Spacecraft",
      "quote": "GPS III SV10 launched from Cape Canaveral Space Force Station at 2:53 a.m. Eastern time."
    },
    {
      "label": "Mean mission duration",
      "value": "12 years, with a 15-year design life",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "The GPS III SV requirements include a 12-year mean mission duration and a 15-year design life."
    },
    {
      "label": "Bus variant (Wikipedia)",
      "value": "A2100M",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
      "quote": "Block III satellites use Lockheed Martin's A2100M satellite bus structure."
    }
  ],
  "features": [
    {
      "text": "Navigation payload designed and built by ITT",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "The GPS III navigation payload is being designed and built by ITT"
    },
    {
      "text": "Subsystems: attitude control, power, thermal, telemetry, propulsion and mechanical",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
      "quote": "The vehicle bus element includes numerous subsystems"
    }
  ],
  "parts": [
    {
      "assembly": "Power subsystem",
      "parts": [
        {
          "part": "Batteries",
          "material": "nickel-hydrogen",
          "form": "battery set (2011 design baseline)",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": "nickel-hydrogen-cell"
        }
      ]
    },
    {
      "assembly": "Navigation payload",
      "parts": [
        {
          "part": "Atomic frequency standards (3)",
          "material": "rubidium",
          "form": "clock",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "Each GPS III SV hosts three enhanced rubidium AFSs",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": "rubidium"
        },
        {
          "part": "Navigation payload element (NPE)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": "Supplier: ITT (later Exelis, Harris, L3Harris)",
          "quote": "The NPE includes the payload computer (the mission data unit or MDU), the L-band transmitters (L1, L2, L3, L5)",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "generates and transmits the navigation signals",
          "specs": [
            {
              "label": "Supplier",
              "value": "ITT",
              "quote": "The GPS III navigation payload is being designed and built by ITT based on its heritage of more than 30 years of GPS payloads.",
              "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
            },
            {
              "label": "Supplier, flight-era wording",
              "value": "Harris Corporation",
              "quote": "our advanced navigation payload provided by Harris Corporation",
              "source_url": "https://news.lockheedmartin.com/2018-12-23-You-Are-Here-First-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands"
            }
          ]
        },
        {
          "part": "Mission data unit (MDU) payload computer",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The MDU incorporates the waveform generator functionality first introduced in the modernized IIR-M SV.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "payload computer with the waveform generator first used on GPS IIR-M"
        },
        {
          "part": "L-band transmitters (L1, L2, L3, L5)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the L-band transmitters (L1, L2, L3, L5)",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "send the navigation signals"
        },
        {
          "part": "Signal filters",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "and signal filters.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "filter the L-band signals in the payload"
        },
        {
          "part": "Fourth clock slot (experimental frequency standard)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The GPS III SV also includes a fourth slot for enhanced new or experimental frequency standard designs, such as a hydrogen maser.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "slot for a new or experimental frequency standard such as a hydrogen maser; the three operational clocks are in the entry bom"
        },
        {
          "part": "Digital Rubidium Atomic Frequency Standard (demonstration, SV10)",
          "material": "rubidium",
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "equipped with a demonstration Digital Rubidium Atomic Frequency Standard clock",
          "source_url": "https://news.lockheedmartin.com/2026-04-21-Lockheed-Martin-Launches-GPS-III-Satellite,-Paving-the-Way-for-Next-Generation-GPS-IIIF-Spacecraft",
          "profile": "rubidium",
          "mid": "rubidium",
          "function": "advanced atomic clock demonstration flown on the final satellite"
        },
        {
          "part": "Optical crosslink demonstration payload (SV10)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "an optical crosslink demonstration payload",
          "source_url": "https://news.lockheedmartin.com/2026-04-21-Lockheed-Martin-Launches-GPS-III-Satellite,-Paving-the-Way-for-Next-Generation-GPS-IIIF-Spacecraft",
          "profile": null,
          "mid": null,
          "function": "lets GPS satellites communicate directly in orbit"
        }
      ]
    },
    {
      "assembly": "Structure",
      "parts": [
        {
          "part": "Basic SV structure",
          "material": null,
          "form": "mechanical subsystem (MSS) with hinges and frangibolts",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null
        }
      ]
    },
    {
      "assembly": "Network communications and antennas",
      "parts": [
        {
          "part": "Enhanced crosslink transponder subsystem (ECTS)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": "Supplier: General Dynamics (communications payload subcontractor)",
          "quote": "It consists of the enhanced crosslink transponder subsystem (ECTS)",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "crosslink and command path of the network communications element",
          "specs": [
            {
              "label": "Supplier",
              "value": "General Dynamics",
              "quote": "communications payload subcontractor, General Dynamics",
              "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
            }
          ]
        },
        {
          "part": "Thin communications unit (TCU)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the thin communications unit (TCU) to distribute commands and collect telemetry, and the S-band boxes",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "distributes commands and collects telemetry"
        },
        {
          "part": "S-band boxes",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the thin communications unit (TCU) to distribute commands and collect telemetry, and the S-band boxes",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "S-band radios of the network communications element"
        },
        {
          "part": "Hosted payload element (government-furnished equipment)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The HPE hosts several government-furnished equipment (GFE) items provided to GPS III.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "hosts government-furnished equipment items"
        },
        {
          "part": "Earth coverage L-band antenna panel",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The antenna subsystem consists of the Earth coverage L-band antenna panel, the S-band antennas, and the UHF antennas.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "nominally Earth-pointing panel that radiates the navigation signals"
        },
        {
          "part": "S-band antennas",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the S-band antennas, and the UHF antennas",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "command and telemetry antennas"
        },
        {
          "part": "UHF antennas",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the S-band antennas, and the UHF antennas",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "UHF antennas of the antenna subsystem"
        },
        {
          "part": "Deployable antenna with 8 JIB elements",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": "Supplier: Northrop Grumman Astro Aerospace",
          "quote": "Each satellite will carry an antenna with 8 JIB (Jack-in-the-Box type) deployable antenna elements, all designed and manufactured by Northrop Grumman Astro Aerospace",
          "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
          "profile": null,
          "mid": null,
          "function": "deployable antenna built from eight Jack-in-the-Box elements"
        }
      ]
    },
    {
      "assembly": "Bus: attitude control",
      "parts": [
        {
          "part": "Coarse sun sensors, earth sensors and inertial measurement unit",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "attitude sensors"
        },
        {
          "part": "Reaction wheels",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "attitude actuators"
        },
        {
          "part": "Magnetic torque rods",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "coarse sun sensors, earth sensors, the inertial measurement unit (IMU), reaction wheels, magnetic torque rods for fine maneuvers",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "fine maneuvers"
        }
      ]
    },
    {
      "assembly": "Bus: electrical power",
      "parts": [
        {
          "part": "Solar arrays",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "primary power source; deployed after the satellite reaches its operational orbit",
          "specs": [
            {
              "label": "Deployment",
              "value": "arrays and antennas are deployed after orbit arrival",
              "quote": "We will then send it commands to deploy its solar arrays and antennas",
              "source_url": "https://news.lockheedmartin.com/2018-12-23-You-Are-Here-First-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands"
            }
          ]
        },
        {
          "part": "Power regulation unit",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "It consists of the solar arrays, nickel-hydrogen batteries, and the power regulation unit.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "regulates power from the arrays and batteries"
        }
      ]
    },
    {
      "assembly": "Bus: thermal control",
      "parts": [
        {
          "part": "Thermal control hardware",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "It consists of insulation, reflectors, heaters, radiators, heat pipes, and thermistors.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "insulation, reflectors, heaters, radiators, heat pipes and thermistors"
        }
      ]
    },
    {
      "assembly": "Bus: telemetry, tracking and command",
      "parts": [
        {
          "part": "Bus computer (on-board computer, OBC)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The TT&C subsystem consists of the bus computer (the on-board computer or OBC)",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "flight computer of the TT&C subsystem"
        },
        {
          "part": "Uplink/downlink unit, remote interface units, deployment device control, event detectors",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "remote interface units, deployment device control, and event detectors",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "command and telemetry path with the GPS Operational Control Segment"
        }
      ]
    },
    {
      "assembly": "Bus: propulsion",
      "parts": [
        {
          "part": "Liquid apogee engine (LAE)",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the liquid apogee engine for final orbit insertion",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "final orbit insertion; raises the satellite from launch orbit to its operational slot",
          "specs": [
            {
              "label": "Flight confirmation",
              "value": "satellite climbs to its operational orbit on its own liquid apogee engines",
              "quote": "will use its liquid apogee engines to climb into its operational orbit",
              "source_url": "https://news.lockheedmartin.com/2018-12-23-You-Are-Here-First-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands"
            },
            {
              "label": "SV04 wording",
              "value": "onboard liquid apogee engine propels the satellite to orbit",
              "quote": "onboard liquid apogee engine will continue to propel the satellite",
              "source_url": "https://news.lockheedmartin.com/2020-11-05-Fourth-Lockheed-Martin-Built-GPS-III-Satellites-On-Board-Engine-Now-Propelling-It-To-Orbit"
            }
          ]
        },
        {
          "part": "5-lbf thrusters",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "the 5-lbf thrusters for large on-orbit maneuvers",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "large on-orbit maneuvers"
        },
        {
          "part": "0.2-lbf thrusters",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "0.2-lbf thrusters for more coarse maneuvers including periodic station keeping",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "attitude control and station keeping"
        },
        {
          "part": "Propellant and pressurant tanks",
          "material": "composite (type not stated)",
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": "Supplier: Orbital ATK (now Northrop Grumman)",
          "quote": "The propellant and pressurant tanks are manufactured by Orbital ATK from lightweight, high-strength composite materials.",
          "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III",
          "profile": null,
          "mid": "fibre-reinforced-polymer-composite",
          "function": "composite tanks for the propulsion subsystem"
        }
      ]
    },
    {
      "assembly": "Bus: structure",
      "parts": [
        {
          "part": "Lockheed Martin A2100 bus structure",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": "Supplier: Lockheed Martin",
          "quote": "The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "basic satellite structure, hinges and frangibolts for deployable elements",
          "specs": [
            {
              "label": "Supplier",
              "value": "Lockheed Martin",
              "quote": "the GPS III SVs being built by Lockheed Martin",
              "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
            },
            {
              "label": "Bus",
              "value": "based on the Lockheed Martin A2100 bus design",
              "quote": "The new expandable GPS III design is based on the award-winning Lockheed Martin A2100 bus design and its long heritage.",
              "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
            },
            {
              "label": "Variant name",
              "value": "A2100M",
              "quote": "Block III satellites use Lockheed Martin's A2100M satellite bus structure.",
              "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III"
            }
          ]
        },
        {
          "part": "Frangibolts and hinges",
          "material": null,
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The MSS consists of the basic SV structure, hinges, and the frangibolts for deployable elements.",
          "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf",
          "profile": null,
          "mid": null,
          "function": "release and hinge the deployable elements"
        }
      ]
    }
  ],
  "materials": [
    {
      "id": "nickel-hydrogen-cell",
      "name": "nickel-hydrogen",
      "material_page": null
    },
    {
      "id": "rubidium",
      "name": "rubidium",
      "material_page": "https://spacemushroom.com/profiles/rubidium/"
    },
    {
      "id": "fibre-reinforced-polymer-composite",
      "name": "composite (type not stated)",
      "material_page": null
    }
  ],
  "standards": [],
  "relations": [
    {
      "type": "launched_on",
      "target": "Falcon 9 (SpaceX)",
      "target_slug": "spacex-falcon-9",
      "note": "launched SV01 (2018), SV03, SV04, SV06 and SV09 per Lockheed; Wikipedia lists Falcon 9 Block 5 for SV05, SV07, SV08 and SV10 too",
      "quote": "The satellite lifted off from Cape Canaveral Air Force Station, Florida aboard a SpaceX Falcon 9 rocket at 8:51 a.m. EST.",
      "source_url": "https://news.lockheedmartin.com/2018-12-23-You-Are-Here-First-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands"
    },
    {
      "type": "launched_on",
      "target": "Falcon 9 (SpaceX), SV03",
      "target_slug": "spacex-falcon-9",
      "note": "second Lockheed-confirmed Falcon 9 flight",
      "quote": "after the satellite's 4:10 p.m. EST launch aboard a SpaceX Falcon 9 rocket",
      "source_url": "https://news.lockheedmartin.com/2020-06-30-Third-Lockheed-Martin-Built-GPS-III-Satellite-Now-Climbing-To-Orbit-On-Its-Own-Power"
    },
    {
      "type": "launched_on",
      "target": "Falcon 9 (SpaceX), SV06",
      "target_slug": "spacex-falcon-9",
      "note": "Lockheed-confirmed Falcon 9 flight, January 2023",
      "quote": "aboard a SpaceX Falcon 9 rocket at 7:24 a.m. EST today",
      "source_url": "https://news.lockheedmartin.com/2023-01-18-Sixth-GPS-III-Satellite-Built-by-Lockheed-Martin-Launches-As-Part-of-Constellation-Modernization,1"
    },
    {
      "type": "launched_on",
      "target": "Falcon 9 (SpaceX), SV09",
      "target_slug": "spacex-falcon-9",
      "note": "Lockheed-confirmed Falcon 9 flight, January 2026",
      "quote": "aboard a SpaceX Falcon 9 rocket",
      "source_url": "https://news.lockheedmartin.com/2026-01-28-Lockheed-Martins-newest-GPS-satellite-reaches-orbit,-strengthening-warfighter-connectivity"
    },
    {
      "type": "launched_on",
      "target": "Falcon 9 (SpaceX), SV10",
      "target_slug": "spacex-falcon-9",
      "note": "final GPS III, 21 April 2026, per the Wikipedia launch table",
      "quote": "21 April 2026 06:53 Falcon 9 Block 5",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III"
    },
    {
      "type": "launched_on",
      "target": "Merlin 1D engine (nine on the Falcon 9 first stage)",
      "target_slug": "spacex-merlin-1d",
      "note": "Falcon 9 first stage burns nine Merlin engines (2010 page; Block 5 flights use the Merlin 1D family, linked to the catalog hub)",
      "quote": "Nine SpaceX Merlin regeneratively cooled engines power the Falcon 9 first stage.",
      "source_url": "https://www.spaceflightnow.com/falcon9/003/falcon9.html"
    },
    {
      "type": "launched_on",
      "target": "Delta IV Medium+ (4,2) (United Launch Alliance)",
      "target_slug": null,
      "note": "launched SV02 in August 2019",
      "quote": "shortly after the satellite's separation from its United Launch Alliance (ULA) Delta IV rocket booster",
      "source_url": "https://news.lockheedmartin.com/2019-08-22-Second-Lockheed-Martin-Built-Next-Generation-GPS-III-Satellite-Responding-to-Commands-Under-Self-Propulsion"
    },
    {
      "type": "built_on",
      "target": "Lockheed Martin A2100 bus",
      "target_slug": null,
      "note": "expandable GPS III design is based on the A2100 bus",
      "quote": "The new expandable GPS III design is based on the award-winning Lockheed Martin A2100 bus design and its long heritage.",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
    },
    {
      "type": "heritage_of",
      "target": "GPS Block IIR and IIR-M",
      "target_slug": null,
      "note": "design elements and the waveform generator come from the IIR and IIR-M satellites",
      "quote": "Important design elements have also been pulled from the GPS Block IIR and IIR-M SVs",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
    },
    {
      "type": "supplied_by",
      "target": "ITT / Exelis / Harris / L3Harris",
      "target_slug": null,
      "note": "navigation payload",
      "quote": "The GPS III navigation payload is being designed and built by ITT based on its heritage of more than 30 years of GPS payloads.",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
    },
    {
      "type": "supplied_by",
      "target": "General Dynamics",
      "target_slug": null,
      "note": "communications payload subcontractor",
      "quote": "communications payload subcontractor, General Dynamics",
      "source_url": "https://insidegnss.com/wp-content/uploads/2015/03/sepoct11-Marquis.pdf"
    },
    {
      "type": "supplied_by",
      "target": "Orbital ATK (now Northrop Grumman)",
      "target_slug": null,
      "note": "composite propellant and pressurant tanks",
      "quote": "The propellant and pressurant tanks are manufactured by Orbital ATK from lightweight, high-strength composite materials.",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III"
    },
    {
      "type": "supplied_by",
      "target": "Northrop Grumman Astro Aerospace",
      "target_slug": null,
      "note": "JIB deployable antenna elements",
      "quote": "all designed and manufactured by Northrop Grumman Astro Aerospace",
      "source_url": "https://en.wikipedia.org/wiki/GPS_Block_III"
    },
    {
      "type": "operated_by",
      "target": "Lockheed Martin Launch & Checkout (Denver) then U.S. Space Force",
      "target_slug": null,
      "note": "Lockheed provides early on-orbit operations before handover",
      "quote": "providing early on-orbit operations",
      "source_url": "https://news.lockheedmartin.com/2025-05-30-Another-Lockheed-Martin-Built-GPS-III-Satellite-Lifts-Off-into-Orbit"
    }
  ],
  "not_published": "No structural, panel, solar-cell, thermal-blanket or tank material is stated in the Lockheed Martin or InsideGNSS pages read. The InsideGNSS article (2011, design stage) names nickel-hydrogen batteries but later says lithium-ion batteries will reduce weight, so the flight battery chemistry is unconfirmed. SV01 mass comes from a secondary source (Wikipedia) and was not matched to a Lockheed or Space Force document. More detail: Not published on the pages read: solar cell type and array maker, the flight battery chemistry (the 2011 article says nickel-hydrogen then lithium-ion for later builds; Wikipedia says nickel-hydrogen), reaction wheel, IMU, sun sensor and thruster makers, the liquid apogee engine model and maker, the bus panel and tank liner materials, thermal blanket film types, antenna element materials, and the makers of the bus computer and uplink/downlink unit. The subsystem list is from a 2011 design-stage article, so the flight hardware may differ. The 2010 SpaceNews page that Wikipedia cites for the Orbital ATK tanks no longer loads, so the tank and JIB antenna statements rest on Wikipedia. Per the sources read, GPS III flew on Falcon 9 (SV01, SV03 to SV10) and on a Delta IV (SV02); no GPS III launch on Vulcan was found. The Delta IV Medium+ (4,2) engines and the Falcon 9 second-stage Merlin Vacuum engine were not sourced here. More detail: Not published on the pages read: solar cell type and array maker, the flight battery chemistry (the 2011 article says nickel-hydrogen then lithium-ion for later builds; Wikipedia says nickel-hydrogen), reaction wheel, IMU, sun sensor and thruster makers, the liquid apogee engine model and maker, the bus panel and tank liner materials, thermal blanket film types, antenna element materials, and the makers of the bus computer and uplink/downlink unit. The subsystem list is from a 2011 design-stage article, so the flight hardware may differ. The 2010 SpaceNews page that Wikipedia cites for the Orbital ATK tanks no longer loads, so the tank and JIB antenna statements rest on Wikipedia. Per the sources read, GPS III flew on Falcon 9 (SV01, SV03 to SV10) and on a Delta IV (SV02); no GPS III launch on Vulcan was found. The Delta IV Medium+ (4,2) engines and the Falcon 9 second-stage Merlin Vacuum engine were not sourced here.",
  "depth": "partial",
  "photos": [
    {
      "file": "products/context/lockheed-gps-iii-1.jpg",
      "alt": "GPS III SV-01 satellite in Lockheed Martin's GPS III processing facility after core mate",
      "long": "GPS III SV-01 satellite in Lockheed Martin's GPS III processing facility after core mate.",
      "kind": "product",
      "credit": "Lockheed Martin for the United States Space Force (https://www.losangeles.spaceforce.mil/News/Photos/igphoto/2002314191/) / via Wikimedia Commons",
      "license": "Public domain",
      "page_url": "https://commons.wikimedia.org/wiki/File:GPS_III.jpg"
    },
    {
      "file": "products/context/lockheed-gps-iii-2.jpg",
      "alt": "Several GPS III satellites on processing stands in the Lockheed Martin cleanroom, tags including SV08",
      "long": "Several GPS III satellites on processing stands in the Lockheed Martin cleanroom, tags including SV08.",
      "kind": "product",
      "credit": "Jason Davidson / via Wikimedia Commons",
      "license": "Public domain",
      "page_url": "https://commons.wikimedia.org/wiki/File:Three_Guardians_GPS_III_(2002838418).jpg"
    },
    {
      "file": "products/context/lockheed-gps-iii-3.jpg",
      "alt": "Falcon 9 lifting off at night from Cape Canaveral SLC-40 carrying GPS III SV09; satellite not visible",
      "long": "Falcon 9 lifting off at night from Cape Canaveral SLC-40 carrying GPS III SV09; satellite not visible.",
      "kind": "context",
      "context": "Launch of GPS III SV09",
      "credit": "U.S. Space Force photo by Gwendolyn Kurzen / via Wikimedia Commons",
      "license": "Public domain",
      "page_url": "https://commons.wikimedia.org/wiki/File:GPS_III-SV09_Launches_from_Cape_Canaveral_Space_Force_Station_(9496887).jpg"
    }
  ],
  "context": {
    "size": [
      "6U and larger"
    ],
    "mass": [
      "Over 100 kg"
    ],
    "orbit": [
      "Medium Earth orbit"
    ]
  },
  "licence": "Product data CC BY 4.0, cite Space Mushroom. Photos keep their own licences, given per photo.",
  "mcp": "https://spacemushroom.com/mcp"
}