"The University of Texas Hacked Starlink's Signal So It Can Be Used as a GPS Alternative"
In addition to providing high-speed internet connectivity to the most remote corners of the globe, the Starlink network's over 3,000 satellites have the potential to do more, such as replace the two dozen satellites that power the Global Positioning System (GPS). After SpaceX rejected the idea, a group of researchers went the extra mile to use Starlink as a GPS replacement. While Starlink's thousands of satellites each maintain a non-geostationary position in low-Earth orbit, and GPS satellites follow one of six different orbits that circle the planet twice daily, they both have one thing in common. They beam signals down to the Earth's surface. The signals from Starlink provide Internet access, whereas the signals from multiple GPS satellites are used by navigation devices to triangulate their exact location on the planet. Todd Humphreys and a team of researchers from the University of Texas (UT) at Austin's Radionavigation Laboratory realized that Starlink could also serve as an accurate and reliable backup to the GPS, but SpaceX decided it was not a priority and stopped cooperating with the researchers. This was a setback, but the UT Austin team did not need intimate knowledge of what the Starlink satellites were broadcasting as they just needed the signals, which SpaceX had no way of concealing. It would have been simple to convert Starlink into a navigation system with SpaceX's help, but without it, it took Humphreys' team nearly two years. They began by purchasing a Starlink terminal and service, which was used to continuously stream HD YouTube videos of tennis legend Rafael Nadal. The setup was paired with a nearby antenna that detected the regularly repeating synchronization sequence signals used by the Starlink service to keep ground-based receivers connected to the satellites. They made no attempt to crack or break the encryption used by Starlink to keep its services exclusive to its subscribers. The repeating synchronization signals are sent at precise intervals. When combined with information about the movement of Starlink's satellites, which SpaceX freely shares online to help reduce the risk of costly collisions with other companies' hardware, the source of the signal and how far away that satellite is can be used to calculate the location of a receiver with an accuracy of about 98 feet. Using these predictable synchronization sequences for navigation across the entire Starlink network poses potential security risks because everyone now knows what they look like, and some will be eager to spoof and fake them for nefarious purposes. This article continues to discuss the demonstrated hacking of Starlink's signal to use it as a GPS alternative.