GPS III SV-06 Successful Launch

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jimh
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GPS III SV-06 Successful Launch

Postby jimh » Wed Jan 18, 2023 10:47 am

The Space Force's GPS III SV-06 satellite was successfully launched into a medium earth orbit (MEO) transfer orbit by a SpaceX FALCON 9 launch vehicle from Launch Complex 40 at Cape Canaveral Space Force Station Florida at 7:24 a.m. this morning, January 18, 2023. This mission was the fifth launch of a GPS III satellite by SpaceX. United Launch Alliance launched one GPS III satellite on a prior mission.

Contractor Lockheed-Martin built the $610-million GPS III SV-06 satellite, and is under contract to deliver four more GPS III spacecraft. Satellites GPS III SV-7 and SV-08 are already built, tested, and are in "Available for Launch" status.

The GPS III series is the newest evolution of GPS satellite technology, and brings improved accuracy and better anti-jamming capabilities to GPS. For civilian users in addition to the legacy L1 C/A (Coarse Acquisition) signal, a GPS III satellite transmits three modernized signals, called L2C, L5, and L1C. For the GPS III series SV-01 to SV-10, the satellites have been given names of famous explorers; GPS III SV-03 is named "Amelia Earhart."

The $52-million launch and powered flight were completely nominal. The 8,550-lbs satellite was placed into transfer orbit, heading for a circular MEO at an altitude of 20,800-kilometers (12,539-miles) by using its onboard liquid apogee engine. As in all GPS satellites, the orbital inclination is 55-degrees. Separation from the Merlin second stage of the GPS III SV-06 satellite occurred 1-hour- 29-minutes 20-seconds into the mission, at an altitude of 4,224-kilometers and a speed of 24,520-kilometers/second.

The GPS III SV-06 satellite will next begin the process of activation and orbit raising, which will take several months. The hugely important first steps are deployment of the solar panel arrays to generate electrical power and establishment of radio communication with the space vehicle. These are expected to be announced shortly.

SpaceX was able to recover the first stage of the FALCON 9 launch vehicle by autonomously landing it onto their recovery ship A SHORTFALL OF GRAVITAS that was positioned about 418 miles to seaward in the Atlantic Ocean. The payload fairings are also expected to be recovered by the support tug DOUG. The Merlin vacuum engine second stage will remain in orbit.

jimh
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Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: GPS III SV-06 Successful Launch

Postby jimh » Thu Jan 19, 2023 10:37 am

GPS III SV-06 will be placed into the GPS constellation at Plane A Slot 2. Currently in that position is GPS IIR-15 (SVN52), which was launched 17-years ago in September 2006. Its operational life span was anticipated to be about seven or eight years--that has been exceeded by double. It has been identifying with PRN 31. The operational lifespan of the GPS III series is expected to be 15-years, but based the performance of other GPS satellites, its operational life could be much longer.

At 1-hour 23-minutes into the GPS II SV-06 mission, Lockheed Martin Launch & Checkout Operation Center in Denver, Colorado confirmed acquisition of signals from the spacecraft; it is now flying under their control, and the process of orbit raising has begun.

Orbit raising to a circular orbit from an elliptical orbit is generally accomplished by firing a propulsion rocket motor on the spacecraft when it is at apogee (highest point) of the elliptical orbit. The GPS III series satellites use a liquid apogee engine to provide the thrust needed to transition to a higher circular orbit. Orbit raising is expected to take at least two weeks.