Lockheed Martin, U.S. Space Force Complete Core Mate of GPS III SV-08 “Katherine Johnson” Satellite

The U.S. Space Force (USSF) has announced the successful core mate of GPS III Space Vehicle 08 (GPS III SV-08) navigation satellite, named “Katherine Johnson”, at Lockheed Martin’s GPS III Processing Facility in Waterton, Colorado on April 15.

The two-day core mate consisted of using a 10-ton crane to lift and complete a 90-degree rotation of the satellite’s system module, and then slowly lowering the system module onto the satellite’s vertical propulsion core. The two mated major subsystems come together to form an assembled GPS III space vehicle.

Despite the COVID-19 pandemic, SMC and its mission partner Lockheed Martin ensured that the GPS III SV-08 core mate took place – in accordance with all Centers for Disease Control (CDC) and local guidelines to minimize exposure or transmission of COVID-19. The GPS III Processing Facility’s cleanroom high bay was restricted to only key personnel directly supporting the operation.

With core mate complete, the GPS III SV-08 space vehicle was named in honor of a NASA trailblazer, Katherine Johnson. With this, the USSF Space and Missile Systems Center (SMC)’s Global Positioning System (GPS) III program reached a major milestone.

GPS III Space Vehicle 1 (GPS III SV01)
The U.S. Air Force’s first GPS III satellite, GPS III Space Vehicle 1 (GPS III SV01) at Lockheed Martin’s GPS III Processing Facility near Denver. (Photo courtesy of Lockheed Martin)

“Core mate is the most critical of the GPS space vehicle single-line-flow operations,” said Lt. Col. Margaret Sullivan, program manager and materiel lead for the GPS III program. “Despite the restrictions presented by the COVID-19 pandemic, our team adapted and worked tirelessly to achieve this essential milestone.”

When the core mate operation is successfully completed, a GPS III satellite is said to be “born.” In keeping with the team’s tradition of naming GPS III satellites after famous explorers and pioneers, SV08 was named “Katherine Johnson” in honor of the trailblazing National Aeronautics and Space Administration (NASA) mathematician and “human computer” who designed and computed orbital trajectories for NASA’s Mercury, Apollo and space shuttle missions. One of four African-American women at the center of the nonfiction book by Margot Lee Shetterly and the movie titled“Hidden Figures,” Katherine Johnson was awarded the Presidential Medal of Freedom in 2015 for her groundbreaking contributions to the U.S. Space program.

Other GPS III satellites have been named in honor of explorers including GPS III SV01 “Vespucci” after Amerigo Vespucci; GPS III SV02 “Magellan” after Ferdinand Magellan; and GPS III SV03 “Columbus” after Christopher Columbus.

The next step for the newly christened “Katherine Johnson” is the post-mate Systems Performance Test (SPT) scheduled to begin in August. SPT electrically tests the performance of the satellite during the early phase of build and provides a baseline test data set to be compared to post-environmental test data.

GPS III SV08 is currently scheduled to launch in 2022.


GPS III is the most powerful GPS satellite ever developed. It is three times more accurate and provides up to eight times improved anti-jamming capability over previous GPS satellites on orbit. GPS III brings new capabilities to users as a fourth civilian signal (L1C), designed to enable interoperability between GPS and international satellite navigation systems, such as Europe’s Galileo system.

GPS Block IIIA Satellite
Artist’s impression of a GPS Block IIIA satellite in orbit.

GPS III satellites will also bring the full capability of the Military Code (M-Code) signal, increasing anti-jam resiliency in support of the warfighter. These continued improvements and advancements to the GPS system makes it the premier space-based provider of positioning, navigation, and timing services for more than four billion worldwide.

GPS III Satellites

Lockheed Martin is contracted to build a total of ten GPS III satellites as the initial batch.

The first GPS III satellite, GPS III SV01 “Vespucci” (USA-289, SVN-74)  was launched on Dec. 23, 2018, and achieved Operational Acceptance on Jan. 2, 2020. USSF made SV01 available for use by military and civilian users for critical missions worldwide on Jan. 13.

The second one, GPS III SV02 “Magellan” (also called USA-293, SVN-75) was launched on August 22, 2019. The satellite achieved Operational Acceptance on March 27 and was included into the operational GPS constellation on April 1.

GPS III SV03 “Columbus” is scheduled to launch on June 30.


In September 2018, the Air Force selected Lockheed Martin for the GPS III Follow On (GPS IIIF) program, an estimated $7.2 billion opportunity to build up to 22 GPS IIIF satellites with additional capabilities. The Air Force also awarded Lockheed Martin a $1.4 billion contract for support to start up the program and to contract the 11th and 12th GPS III (the first two GPS IIIF) satellites.

GPS IIIF builds off Lockheed Martin’s existing modular GPS III, which was designed to evolve with new technology and changing mission needs. These will include a fully digital navigation payload, a Regional Military Protection capability, an accuracy-enhancing Laser Retroreflector Array, and a Search & Rescue payload.

Lockheed Martin is expected to soon complete its critical design review with the Space Force to begin production on the first two GPS IIIF satellites under contract. The first GPS IIIF satellite is expected to be available for launch in 2026.

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